If you watch live data on any fuel injection engine it will show a high timing at idle and low load. This is why vac adv belongs in manifold vacuum. The trick is to mod the vac can to only add 10-12° so my engine is 12 base and with vac adv its 22 at idle. As the part throttle cruise increases the vac it stays adding 10° while the distributor weights add timing. My distributor is 22° of weights all in at 3k. But either way an engine needs most timing at low load and high rpm. So a situation of part throttle cruise where you are going maybe 30mph you want like 45-52° timing. Because what nobody understands is a lean mixture needs more time to burn!
Another great video my Edelbrock 2065 dual quad set up arrived 2 weeks ago I ordered it 8 months ago the metering rod's were bouncing at idle 300 duration cam I put in the blue springs and they stay down at idle, I'm sure there is more tuning to be done idles great in gear plugs are tan colored and it's a frickin blast when I put the pedal to the metal in my 68 Camaro good guys in Puyallup is 2 weeks away I'll be there keep the videos coming
So I bought a cheap Amazon kit changed out couple gaskets and I messed with my idle screw once I put it all back together and put it on. I think it’s a really high idle and now I’m getting that ticking noise. Thank you for the clarity love your videos and clear knowledge.
I have a 65' thunderbird with the 390FE. I have the Edelbrock performer intake manifold, lunati camshaft just a bump up from stock cam specs,. shorty headers,.etc... my engine vacuum was 19-20 (green zone on the vac gauge). I called Edelbrock and they told me to put in the silver spring into my 650avs2. Runs fantastic .
Excellent video as always. Thank you. Your point about timing is very interesting. I am at 5300 feet and when I set the timing to the shop manual specifications, my engine ran terrible. I advanced it and always figured it was because of altitude, despite there being no good references or agreement as to how many degrees you should add per thousand feet of elevation. I can’t remember how many additional degrees I added, but I think I went from something like 5° (spec per the manual) up to about 10 or 12 BTDC. I worried that was quite a bit of advancement. Your comment about today’s fuels was very interesting and something I was unaware of; that may be part of why i had to advance the timing so much. Once I set my timing ( I pretty much just set it to where the engine idles well and does not ping under load), the carburetor was easy to adjust.
At that elevation I start at 14-16. I did a video on tuning for elevation. Gotta have more time to burn when there’s less oxygen and the fuel is absolutely awful!
In my hobbies I look for the Jedi master to teach me. I’ve found you! My interest in the functionality of the rods and springs is triggered by a horrific discovery on a purchased edelbrock. I wish I could post a photo. The left cover cannot be opened to remove the rod. Appears fused or god knows.. below that the casing has broken open and I can actually see the top of the piston. What on earth could have caused such destruction? Guess I’ll be looking for another 600 right?
Hey Boss, love your educational videos, if recall our conversation a couple months ago, installed the in the tank EFI Bosch fuel pump, having 6an fuel lines & Holley regulator for my 91 Jeep YJ with the 383 stroker and the AVS2 500 cfm...Runs absolutely perfect now. Will begin tinkering with the fuel mileage now since the Fast AFR was also installed as well.Keep up the awesome information, it's appreciated. 👍
There’s some small gains that can be made with a good tune. If you’re chasing bigger MPG numbers though, you’ll find those in the transmission. More gears = lower operating rpm and more economy. Sounds like you’ve got a great set up! Dependability is your biggest success with that set up. Keep tuning!
Awesome video man, great information and easy to follow. I’m new to carbs and about to rebuild a 1406 for my 350 k5. Thank you so much for what you do. And for the tip about the 12 degrees before TDC.
For sure timing is what gets everyone at first. It fixes quite a number of their perceived carburetor issues. With todays fuel, 12 is my go to starting point for the elevation I’m located at. Best of luck on your rebuild! Don’t hesitate to let me know if you have any questions. Happy to help if I can.
I saw an advertisement on the internet selling the springs and they are red! I have a suíte case with a calibration kid and I remember that there was no red.But the color of the springs went out...All that was left was the pink.The other collors went out. I'm going to have to put the menhirs in ; I think the blue one is smaller! I have very low vacuum at idle! When I shift into gear to maneuver the engine stalls! Based on your explanation, I will have to put It in blue! What if the blue one doesn't work?? My valvetrain is Crower 292/298 with 107 lobcenter! I bought 0,2mm steel wire to make weaker springs!
Great vid on the step up spring operation as to knowing that the metering rod piston should pop up when you snap on the throttle and that's when you got the right springs in
Tank you! Sou do Brasil, esse vídeo confirmou minha suspeita! Tô com um comando Crower 292/298 no motor GM 250 cid Em marcha lenta está dando excesso de combustível! Vou colocar molas mais fracas!
@@MuscleCarSolutions I didn't look até the vacuum gauge, but it's definitily low! Due to the Crower 292/298 command having a center lob of 107.Engine is a 6 cylinder GM 250 Cid!
I have one sticking in the jet on one side and once engine is up to temp it idles rough and loss of power and when reving it up cold or warm I hear a whistle like a vacuum leak. Sprayed base and nothing leaking. Works great when engine not fully up to temp
i'm going to have to look and see what springs are in mine. I should probably order the kit first. I did add a fuel pressure regulator and gauge. gauge showed 7psi, but regulator is supposedly calibrated to 6.5psi at the factory so i assumed my gauge is 1/2psi high and set it to 6. Before adding the regulator it was showing 7.5psi, so probably a little high for my carb.
Been driving w my 1406 w AFR , Tach and VAC gauge on the dash for almost 3 years now. Fat old Dodge. Cruise and tow. Lookin for MPG & Tow power. Noticed some stuff. * jet. Jet. * timed enrichment. - nothing is perfect. - more of a compromise. Keep it in the middle AFR - 11.5 to 16 seems to work.
Great video, I love it. Question i have a 86 ford bronco 5.8 engine with a brand new AVS2 carb and have a mechanical fuel pump should i changes to a electrical pump. Thanks
That’s going to be a preference choice. I will always prefer to run an electric pump. But I also run mechanical pumps with no issues. Your 86 likely has a return line back to the tank which is good. I’d still add a regulator so you can tell the carb how much pressure you want it to receive.
Need to break that down into areas of operation. Idle, off idle, cruise, power. If you’re having an issue in one of those areas, then determine if it’s a lean or rich condition. You can then start making adjustments from there. Here’s where an AFR earns it’s money. Takes all the guesswork out of it.
If you will put that distributor on manifold vacuum, it will be a lot more responsive and have more vacuum at Idle. I know that this was only demo purposes but that would be a good video to show people.
@@AdamDixonSR that’s incorrect. It’s not the only or best option 100% of the time. Not sure how that internet fallacy started, but there’s a reason why the two ports exist. All depends on the cam profile and engine set up.
Just spent 2 days tuning my buddies 77 351m with an afr and have it dialed except for one specific throttle input cruising slight load and WOT is spot on but i could not fix a rich condition at around 2/3 to 3/4 throttle didnt matter ifbi had the rods set for the leanest setting with the lightest spring it still maxes out the afr at 10 to 1 at that specific spot this is with and edelbrock 1406
Awsome video.. im hoping you could help me with this. I just bought a new elderbrock 1405 carburetor manual choke 600cfm and im having issues with just off idle like a stumble or a bog and I can't figure it out.. I went from a Quadra jet to elderbrock.. ive checked timing it was a bit low moved it to 12 degrees.. ive installed new fuel filters and a new stock mechanical fuel pump the engine is a stock 350 in a 1976 chevy k20 manual 4 speed. Only other change I have done was a elderbrock intake and headers and also the plate to make it go from spread bore to square bore. Any help would be appreciated im just lost on it..
Hi, i have a tbi 5.7 sbc converted to carb, but i dont know much about setting time correctly on engine, i know there are 3 sets of time but dont know if wprks for stock engines , i have seen that in modified engines, would be great if you record a video explaining all that settings, love your videos by the way, i have learned with them, thanks
Your videos have been incredibly helpful. I appreciate all the information! I’ve just installed a 1406 on my 454. It has greatly reduced my over rich issues at idle and at cruising speed. I am however having an issue with a burble or slight stutter under very lite throttle. As I am just easing through town and it’s almost as if there’s a miss. I have to assume it’s this step up spring and buy this video it sounds as if a slightly lighter spring will help keep the metering rod in the jet well under very light throttle? If I’m understanding this correctly I am probably seeing the metering rod bouncing up and down when I’ve only just come off of idle and the engine is under very little load.
It’s possible. Difficult to know without knowing what your engine vacuum is at that rpm. But springs are very easy to change you and can make some trial and error type adjustments to see if that is the cure.
@@MuscleCarSolutions thanks for the response. I’ve got a tune kit on the way. I’ll get out there and potter with it. Your videos have been a huge help. Thanks a million.
What about adding a 1" spacer to help with heat soaking? Will you need to make any adjustments? If so, what does it affect after the existing set up? Thanks
Yes to adding a heat blocking spacer. No, you won’t need to make any major adjustments. Unless you’re data logging and have that to work from. Seat of the pants you’re not going to feel much. In most instances anyway.
I have an old school sbc350, I installed a new cam and intake manifold it runs good but when reading the plugs it looks way too lean, which spring will richen up my avs2 650 carb. Thanks. Phil
Great video Good information i a question when im driving around 30mph and step on the Accelerator It hesitates ?Then takes off is that timing or Carburetor adjustment
@@timothycorya1536 so you’ve got a good start. I’m going to assume you haven’t done any tuning. First thing to do is verify if it’s a lean or rich condition. Move the accelerator pump rod up to the top hole (closest to the pivot point). Does it get better or worse? Try to keep an eye on the rpm this occurs if your problem still exists.
i have a 1983 monte carlo v6 3.7 dual jet edle carb i did a replacement the other one was broken but now i have high idle any tips to fix this i watched a few of your other videos on some good info but wondering if theres any other tips and tricks ? the old carb made it stall when switching gears to drive and reverse the new one just has a high idle idk exactly whats up
I really appreciate how thorough your videos are , truly , I'm having an issue with a 1406 right now and could use some help. I have great responce from throttle , starts great , but runs rich , I've adjusted the idle circut out a bit due to running rich, adjusted idle mixture , timing ect Nothing helping , the electric choke is not connected to any voltage. Running rich , and spuratically runs fast then drops to almost stall , takes a bit of feathering on throttle to keep it going. Then all is good. Makes no sence to me. 15 vacuum and 5 psi fuel. Any help in the right direction would be great . I really cant see the choke not being hooked up doing this but hell , maybe
With regard to removing the spring/piston/rod and just running on the jet, besides running extra rich and being unable to install a sufficiently small jet, you'd be creating an internal vacuum leak since the piston is no longer there. Sure, the piston doesn't have rings and doesn't really "seal" to its bore, but it does provide an impingement. After all, if it didn't, it wouldn't be pulled down by vacuum in the first place. I suppose the piston could be installed by itself, but that would do nothing for the rich mixture.
Have a 1934 outlaw, timing is good. Have a 650 edlelbrock when I’m cruising it’s fine when I punch it , it bogs and falls on its face. 383 stroker mild cam . Any help would be appreciated I follow and trust your videos thanks for taking time to put them out there.
@@stillwaternyc9707 gotta know the details and I’ve got a bunch of questions! What’s your initial and all in time set at? Can you share the cam specs? What have you done so far to tune the carb? Do you have a calibration kit? What is your vacuum at idle and what step up spring did you use?
My Chevy 350 with the edelbrock 1406 bogs pretty hard when I floor it at low rpm. Rolling above 2500 rpm or so it seems to take off fine. Would I go down to the yellow step up springs or up from the stock orange springs in there now?
my 454 runs 21 vacuum at idle, I run a 800cfm AVS2 and edelbrock 1722 fuel pump (brand new saddle gas tanks and tank switch) on it. Its pretty much all stock rv cam stuff as far as i can tell, with peanut port heads. I run at total of 35 advance without va and using a reliable digital timing light, I am using manifold vacuum for VA, I cant remember the jet sizes but I am pretty sure i left them stock when I bought it, and I confirmed float levels are good. I sometimes deal with a bog from part throttle to wot at around 2k-2,500k rpm, that is around 45-50mph at part throttle to wot when it happens. It starts missing and jerking, losing power feeling like its about to die but not a solid bog but like trying to go more but getting hit with bog real quick over and over. Its very hard to explain, but I am curios what would you do in my situation? I thought to check the boots on the dizzy too make sure there is good contact, but any suggestions for spring size (i run orange atm) would be appreciated.
You’ve got a couple things there that are fighting each other. First, 35 all in timing is likely ok. What’s your initial? Why are you running on full manifold vacuum? That advance you’re getting at idle and off idle aren’t really necessary with a stock type cam and engine. I’d be willing to sacrifice some of that vacuum. 21 is great, but when you start tuning it’s ok to lose a little bit of that to gain back some power down low. You can pop in the silver spring to start. Then start tuning. You can even back the accelerator pump position down to the middle to see if it makes it worse or better. You might be getting a bit too much fuel. That and the spring change will help you confirm that. One adjustment at a time to see if you’re on the right path.
@@MuscleCarSolutions The initial timing fell at 14 to make a total of 35 at 3500rpm (it did not advance any further past that i confirmed) with va unplugged and capped. I switched to manifold because response feels much snappier off idle and my understanding is Ported was just an after thought pushed by the EPA to make your exhaust run hotter and burn more biproducts in the emissions. Everything feels great besides the occasional crazy stumble/bog i get at mid throttle to wot. When i use VA ported i idle at 14 degrees, with manifold i am idling at 34 which is too be expected with the extra vacuum, which means my canister is giving 20 degrees advance at full manifold vacuum, i may check if its adjustable but i feel like this is not that issue as it happened before i used manifold. Honestly the Manifold is supposed to keep your engine cooler at idle and i will say its much smoother from idle to wot, i can easly spin the tires there its just under partial load at part throttle to wot it starts doing the bog/stumble shit.
@@stormwolfgames6636 I would check your fuel pressure and check the float drop and float height to make make sure they are in spec because it sounds like your running out of fuel in that mid to high wot . Make sure to run a phenolic heat spacer between the carb and intake so the fuel stays cool and doesn't cause issues of boil over and flooding or vapor locking which can happen especially with the fuel we have that has alcohol in it . If possible run a 3/8 ths fuel line from the tank to the carburetor to make sure it's getting enough fuel and try to run at least 1 fuel filter but I usually run 2 ! 1 before the fuel pump and 1 after to keep any crud from going through the pump and into the the secondary fuel filter and I've noticed as of late that these cheap plastic fuel filters now don't filter very good at all so stay away from them if possible and try to use the metal filters that are used for fuel injection instead because they filter down to much smaller micron particles so the injectors don't get plugged up plus the plastic fuel filters now are so cheap you can actually see them pulsate from the fuel pressure which could possibly cause a failure of the filter cracking open and leaking fuel on a hot engine or surface . Fuel pressure should definitely be check out and set with a fuel pump regulator so it stays consistent because too much and you start pushing the needles open off the seats and cause a rich condition and flooding and too much fuel can actually cause fuel wash in the cylinders where the fuel is actually washing the oil off the cylinder walls which can hurt the honing marks in the cylinders and eventually the rings won't seal correctly and compression will drop because of this especially if it's way over jetted . I'm on here because it popped up on my TH-cam feed and decided to watch this because I have run these carburetors on many different engines through the years and usually they are a pretty good carburetor and are a ok street carburetor but for racing I would rather use the older Holley double pumpers or even that new Edelbrock Brawler that's out that is basically Edelbrock's version of a Holley that I hear are good .
@@peteloomis8456 So I actually just bought a heat shield spacer gasket from edelbrock, gonna give it try because when the weather was a little warmer i think i was having some vapor lock issues since i am using a 2 port fuel pump now instead of the old 3 (In, Out and the Return line!). I would rather run the return line as it was designed to avoid these issues and keep the fuel cool, but there is no fuel pump designed for a big block that does not at least get a little bent at the nipple because the can is a bit too long for a bbc swapped into a 1/2 frame. I mean it worked for awhile like that, but it always bothered me the main in line i believe gets bent a bit by the crossmember. Anyways so thats why i havent been using the return line, which is why my first guess after spark (which i triple checked and is good) was overheating fuel. I noticed when i had my wife pump the gas with the truck off so i could confirm throttle plates are opening all the way, after running it to op temp and around the block, the gas was evaporating as soon as the booster poured it in because the carb was getting so heat soaked. I am guessing that is what is happening in this wot moments when the engine is getting its hottest the carb is just absorbing all that heat and the fuel is just evaporating and causing a percolated situation i guess. I will install this heat shield gasket and let you know what my results are.
If you put a step up spring that is stronger do you have to but the accelerator pump back to where you moved it from mine was in the 2nd hole and I put it in the bottom one and I put step spring in the one after 5hg
Those adjustments are never permanent when tuning. So yes try it as you work through the process and see if it makes it better, worse, same. Don’t forget to keep working timing as you go through this is changes.
What size meter rod would you use on a 496 stroker motor 800CFM ... I put in the plain step up springs but never changed the meter rods ..I'm reading 16 vac
Don’t just randomly change rods or jets. Follow the tuning chart. It will lead you in the right direction. Just determine if you want to add more fuel or take it away.
are these springs ok to use on quadrajet carbs that you know of? its nice that they are labeled if an engine has 14 inches of vacuum in your experience what spring would you recommend?
i have a question for you! i have my cruise and idle mixture about perfect as well as timing set. super crisp throttle response and wide open throttle response feeling great! i have a 1986 suburban big lift 35" tires with 4.88 gears, powered by a 383 stroker (ATK HP33) with a 650cfm avs 2 paired with a 700r4 if i am at cruising speeds and roll into the throttle under load eventually the afr goes stark rich 10.0 flat same thing happens when in overdrive and climb a grade vacuum drops to near zero and afr goes full rich even when secondaries have not opened. i have been through multiple jet and metering rod changes and best i can get is 10.5-10.7afr why am i getting this rich under load if all my other afr's are good around town/idle and even wide open throttle? what can i do? thank you for all your videos please keep up with all the awesome information
@@MuscleCarSolutions initial timing set at 16 degrees and 35 all in. I am running the “progression ignition” hei distributor and have played with timing with little to no change. I am on #10 with 68-47 rod pink spring also running the 800cfm accelerator pump and 33 nozzle . I am at 2200 elevation
got a 1404 on a 302. problem I'm having is the metering rods, both of them, are getting stuck down when engine is running no mater how much I push the acceleration, but will pop up when engine shuts off. any suggestions for this?
@@dennissteege the engine vacuum holds the rods down until load is applied and vacuum drops. They should be fully down at idle. You’re not metering fuel through the main metering circuit at that point. There is no suggestions. It’s operating as it should! Follow the step up spring tips in this video and keep them in mind as you work through the tuning process.
Having issue with my 1406, no matter which springs I use for power adjustment, the vacuum pulls the metering rod down but the drop in vacuum does not occur when increasing rpms or goosing the engine. Tried all the different springs with no change.
@@MuscleCarSolutions Thanks for reply, love your videos. Since sending my question, I changed only the metering rod to a 70x37. It seems the stock rod was not releasing. I also had to put a #8 spring in to make it work. So now I'm in the process of installing an AFR meter to tune the carb. Wondering if you have a suggestion on AFR reading. Towing 3000 lb travel trailer. Truck if chev 350 with RV cam and 373 gears, 2 wheel drive?
@@MuscleCarSolutions Another question, waiting on calibration kit to arrive, borrowed a kit to troubleshoot, so the plunger bounces with the 70x39 metering rod and stock `.098 jet and #8 spring. Regarding the primary circuit what do you recommend the tuning steps using AFR? Also should I be making any changes on the secondary jets which are stock .095
Every time i have to drive up a hill and there is a stop sign had to stop and when i try to go my engine feels like wants to die i need to put a bigger spring or smaller spring i have a 350 engine and avs 2 edelbrok carb???
I got an afr gauge my idea is very close but when rpm goes up I’m getting a rich reading will a spring change fix this or is a jet size required? The gauge reading is around 11-12
What spring would you recommend if 350 small block runs rich. Has mild cam and timing is correct, pulling 12 on carb vaccum. Spark plugs wet and smell like gas. Any suggestions would be greatly appreciated.
@MuscleCarSolutions yes its 12 on full manifold vaccum. Engine timing is set 12 degrees before tdc on idle. I don't have information on mild cam. If I remember correctly it's at 35 degrees at 3000 rpm.
@@nursecuenca if you can only muster 12” of vacuum, that’s generally due to a fairly radical cam. Unless you have some other issues. What step up springs did you put in?
@MuscleCarSolutions It has original spring that came with carb. Just wondering what spring size/color to use in order to lean mixture. I'm new to classic cars and have learned so much from your channel and your knowledge
@@nursecuenca hard to say. If you haven’t bought a calibration kit, you’ll need one. It comes with all the springs. The tuning chart has the spring color and it’s corresponding vacuum rating. If you’re at 12, the stock spring in an Edelbrock carb is the orange spring, rated at 5”. If it’s released and flowing fuel too early, then drop down to the yellow spring. That will open later as the vacuum will need to drop below 8” of engine vacuum to engage. But there’s other things here you need to verify first. Fuel system set up. Run a regulator at set at 6psi. I don’t know your elevation to know if 12 advance is enough. I did videos on both of those topics. Before you start making carburetor changes, you have to set the fuel and ignition systems up for success. If you don’t, there is little to no tuning that can be done.
I have a 1970 Impala with a modified 350. 10.25 compression, aluminum heads, comp cam 530 lift 280 duration and an Edelbrock street performer carb. Runs good until the engine gets completely at operating temperature then it stumbles a little as I slowly accelerate. I have a AFR gauge installed and the ratio when it’s doing this jumps around 15-16. All else it runs a good 12-13. Accelerator pump is in the richest hole. Stock meter springs are installed. Any ideas? Thanks for your great videos!
What rpm is this occurring? The accelerator pump shot is a short window/amount of operation. Depending on when you’re experiencing this, it’s a power or cruise mode change. You’re very smart in using the AFR. Now you know which way to go in the tuning chart! This video will help you dial in the step up springs.
@@MuscleCarSolutions I’ll pay attention to the rpm. Additional I do have pre and post electric pump filters (100/10). The carb is stock except the accelerated pump being in the closest hole to the pivot point. Revs like a race car but just has that little hesitation hot. I have a metal carb plate between air gap intake and carb. Thanks for your quick reply!
@@blessedlife1039 ah. Well you’re ready to start tuning! Also the metal spacer is problematic if you’ve seen my videos on heat soak. Spacer isn’t a bad idea and using a phenolic plastic or wood laminate spacer will help keep the carb cooler. You’ve got the right filtration set up. Got everyone lined up for a easy tune!
I used your videos extensively to set up a 350 SBC with a 1411. While this is not ideal, I did not want to buy a new carb since the 72 Blazer will be getting a gen V L8t motor soon. The 1411 was on the Blazer when I bought it. It now runs pretty good and my AFR gauge reads about where I am happy. It took a while to find the right combo but I am feeling good about it. 104main jet/100 secondary, 68x47 rod and plain spring
On that carb one one is for GM vacuum while idle the other one there is no vacuum at idle for AMC , Chrysler and ford. The tube needs to be on the driver-side line , after timing with out vacuum.
I put in a avs2 800 cfm and went to change the spring and rod today. The driver side came out with ease. The passenger side is stuck I can get it out about halfway and it binds onto something. Also doesn’t move freely like the drivers side does and seems to keep getting hung up on something in there…..is this carb a dud? Ever come across this issue?
@@gurtajdhillon23 nope. The avs2 is always a little more tight with the air valve secondary tower taller and a little more restrictive. Take it off the engine if need be and completely remove the piston cover if necessary. Unless the rod is bent, then pop the airhorn assembly off and you’ll know instantly if that’s the case.
love you videos. Couple questions, when does cruise mode stop and power mode begin? Is that based on stepup spring vacuum rating? Should the secondary flapper thingie be adjusted so it opens when the step up spring pushes the rod up? Your tank, filter, pump, filter, regulator, carb drawing is missing the fuel pressure gauge :)
I have a problem that i cant figure out how too solve. My engine have around 14hg vacuum at idle. But when i put it in drive the vacuum drops to 12. So need 5hg step up spring to hold it don at idle. But with 5hg spring its lean at power mode. Have at about 15hg vacuum att light throttle(power mode). What can i do to fix this ?
Im new to the old school scene and need some help on what spring you think i should use, im still a bit confused cuz im so new with this stuff. I got a vega with a 327 with some old double hump heads, medium cam, a performer intake and now the avs2 650.. did the timing by ear and tuned the carb by ear and feel, it ran great and strong for months but now fouls plugs and always seems to run rich and was just hesitant off a red light and stumbled and also stumbled full throttle when the secondaries kicked in i think... the step up springs are factory never touched em and never touched the secondary throttle blade tensioner screw either.. any help will be greatly appreciated
Ok first, there is no tuning by “ear”. Get a timing light on it. Depending on your elevation, 12-18 initial. Get a vacuum gauge on it. Find your full manifold vacuum at idle. That will help you make your initial spring choice. That can change later as you continue tuning so be prepared to make some adjustments of when you want the fuel introduced. Get a calibration kit. The 650 is a lot of CFM for that engine. Without knowing any specs on the cam, it’s practically impossible to decide on the right CFM that engine needs. But to you’ve already made a choice, then you’ll just have to do the best you can to get it dialed in. Get a pressure regulator and gauge. Regulator is the last thing in the fuel system before the carb. Set at 6psi and you can adjust down as low as 4.5psi. Downer matter of you have a stock pump. Get the regulator and give yourself that ability to adjust. I did a separate video on how to adjust the AVS. That will help you understand which way to go and WHY. No need to be frustrated. You just haven’t started tuning yet.
@@MuscleCarSolutions thank you, really appreciate the help. I'll go off of this reply and try to get it dialed in the best I can. Thanks again 👍 I'll check out your other vid on the avs as well
Hey Buddy I'm back to let you know what I have found out...I bought a vacuum gauge and followed your instructions but just wanted to ask you to weigh-in on what I have found... at 1 1-2 turns (factory setting) A/F ..I barely made 5 inches of vacuum but screwed the A/F all the way in and I could almost get 9in, but really I should say 8.5 to 9 and it bogged down when I screwed out I havnt adjusted the floats but I did get a air chuck with a rubber tip and blew each side out on the af and checked the tapered tips( clean,no ridge).....my ignition is a MSD Digital digital 6al MSD Pro-Billet Dis. and a Blaster 2 coil. I should mention I gapped my plugs .45 thousand...but I'm smelling gas in the exhaust and l have the Accelerator Pump in the middle hole....What Step-up should I run?, MY last plugs were heavy carbon fouled with white electrodes and a rusty red color at 2,000 miles meaning what? Timing is at 35 and I have my vacuum secondary hooked up to the drivers side port of the AVS2 the engine is 2,000 miles old completely new...I can't tell you how much I appreciate your help and time your an invaluable resource
@@MuscleCarSolutions No sir, At 2500 aprx I am 35 degrees and my cam is a 226/236 589/589 110+4adv@50 but with 1.5 RR it's 540 lift? I set my timing with the vacuum advance plugged
@@richardclary6267 ok so what’s your idle rpm? If it’s more than 1000, then we need to try and get it back under that to get it out of the transfer slot. Something is pulling too much fuel. You can try dialing back the fuel pressure a little but on that cam I wouldn’t go too far with it. It’ll let you know if it doesn’t like it. Getting the idle under control would be a good place to start. Assuming you mean your vacuum advance hooked up to the full manifold vacuum. Might give it a go in the ported side. Check your initial timing again. If it’s under 12 you can add more and see if it helps with the idle control and the rich condition. Not sure what your elevation is but again when you get to an area it doesn’t like, it will tell you with hard starting and some detonation. I’d begin there first and you can build on the step up springs from there. That way you can verify engine vacuum at its best scenario instead of chasing things aggressively back and forth if you make a big spring change based on what your idle vacuum is right now.
@@MuscleCarSolutions idle rpm is from 500-650 its not steady because of the lope..ok so yesterday I noticed that my Holley 110gph fuel pump was on 8 I backed it off to 6 1/4 psi (rock solid no needle movement) ill se if i can find out how to lock out the distributor and I am going this evening to but new carburetor gaskets my old ones were fine, but I'll buy new ones anyway, I'll check my timing ASAP and let you know initial and I'll change to port (drivers side) Buddy is it possible the 650 is too small Edelbrock puts the 800cfm on these motors as 350's why? Also I put the Yellow springs in? Thanks
I'm running a Carter 9635 on a mild 302 that I'm having trouble tuning a horrible WOT bog out of, I may have to play with the springs after finding out how much vacuum I'm pulling. It's bad enough that the car has stalled trying to go wide open. Changing the position of the pump rod has made absolutely no difference. Idles just fine, seems to be ok if I roll into it, just WOT giving me issues.
@@MuscleCarSolutions Sorry, I wasn't very specific. .030 over, Summit cam 216/216 @ 050, .485 lift 110 LSA, Chinese Edelbrock knockoff intake, headers, some basic port work on the heads, 58cc chamber factory heads. 625 could be a little on the big side I guess, but I do have a 500 cfm Edelbrock that I could throw on and try.
Not a mild cam, not really aggressive either. You’re kind of in a gray area there. I’d concentrate on either tuning the carb that’s on it now, or switch to the 500 and tune it. Just as a wild guess, but I think you’ll find better luck with the 500. Certainly better throttle response and easier to tune for that cam profile. Get a calibration kit, make sure your timing is set (12-14 initial and 32-36 all in), fuel system is up for the job (regulator and a gauge would be a must for either carb choice), and see what you can work our.
Where would be the best place to get a set of springs for a EdelBrock 1406 going on a 302 ford motor? Motor is NOT stock cam wise, rather bigger cam. but im wanting to learn this so I know everything about this carb I can know
Found this after the sec tuning vid... to continue ...my 283 is .030 over, heads shaved .003 for trueness, as i said in other vid comments i have a rare 2 yr made gm 327 intake on it. Vac was running right at 20 but since then and only less than 400 miles on it, its broken in some and i took a little timing out of it. What springs should i be using. Havent been in the piston springs yet to see, if orange is stock then ill assume thats whats in it.
@@charlespartak2435 hard to say with the limited information, but assuming you’re close to sea level and your timing is around 12-16 initial and you’re getting that 20 inches of vacuum at idle, then run the silver-plain springs.
Today I installed a 1906 650 CFM electric choke on my 383 engine. Borrowed an AFR gauge from a friend and ran the engine just as it came out of the box except setting the idle speed and AFR. On my test drive I get a very lean reading on light to medium acceleration like high 15 to low 16 but on cruising at 55mph at 2000 rpm I am reading high 12 to low 13. Everything I see on the chart I see that if I do a change on one it makes the other worse. I have not changed anything yet, just wanted your input on this one. I was thinking maybe a softer spring? My vacuum is around 14 in park and 12 in gear holding the brake. Your thoughts would be greatly appreciated. Also btw I really like your videos. They help me a lot or at least give me a lot of ideas which might be scary :)
@@andyspence4014 absolutely set the springs first. Right now you don’t have enough good info coming from the carb to make any rod and jet changes. Make the spring adjustment first, then verify the accelerator pump shot and then you’re ready to start making changes based on the tuning chart. Good move using the AFR. It will dramatically reduce your tuning time. But beware! You may come back to springs again as you work through the process if you need to change opening events.
just put a 1407 750 on a 396 with a cam that has 6-7 vacuum at idle. It's a bit rich at idle so after watching this I'm thinking I'll try lighter springs and possibly a metering rod change depending on how that goes. Thanks!
@@MuscleCarSolutions yeah friend bought the wrong cam and heads lol. I'm just helping him out. He also had Fitech which was awful so I removed that and put on an edlebrock with aeromotive dual fpr setup
@@oldchevy5512 well, you didn’t mention what elevation you’re at but here at a little over sea level, I generally start at 12-14 for initial. Higher elevation will change that starting point.
Thanks wasn't sure on elevation I guess more or less I swaped from tbi to carb runs good but it starts dieseling when turned off but thanks for the info
@MuscleCarSolutions I would really like to see a video with a vehicle that stumbles off idle when you floor it but runs great off idle. I would like to see the steps you take to tune the stumble out of the vehicle right at the start as you floor it off the line.
Only problem that I have had with springs is edelbrock paints the orange spring yellow and the yellow spring is an orangey copper color, why not use 4 colors that aren't close in color?
Edelbrock instruction book says plug into manifold vacuum, I see your in ported vacuum, also I see you have an adjustable vacuum advance and the instructions on an Accell vacuum advance also say to go to manifold vacuum.
I’ve always run ported on mild street engines. Best way to get the full range of timing and there’s zero reason to run full manifold vacuum when it’s not needed. The Edelbrock instructions suggest full manifold vacuum with aggressive, long duration cams which this engine doesn’t have.
I swear I have spent more time and money than what the carbs cost new . And still not right. . Must be why there are so many Edelbrock factory refurbished carbs for available.
@@GregBallard-e1p literally the easiest carbs to work on and adjust with the tuning chart. Get the fuel system right. Put some timing into it. Follow the tuning chart. Extremely simple if you follow that recipe.
They are simple to work on yes , but with two 600cfm's . Along with a 246 dur 596 lift 110 sep cam . 8" vacuum . . Timing 18 deg initial 18 deg mech all in 2800rpm I need more than the idle cruise , power mode and step up adjustments that are available. In reality I am looking for perfection , when there is no such thing.
If you watch live data on any fuel injection engine it will show a high timing at idle and low load. This is why vac adv belongs in manifold vacuum. The trick is to mod the vac can to only add 10-12° so my engine is 12 base and with vac adv its 22 at idle. As the part throttle cruise increases the vac it stays adding 10° while the distributor weights add timing. My distributor is 22° of weights all in at 3k. But either way an engine needs most timing at low load and high rpm. So a situation of part throttle cruise where you are going maybe 30mph you want like 45-52° timing. Because what nobody understands is a lean mixture needs more time to burn!
Thanks Man,...your words helped me alot!!...67 Plymouth Belvedere 440 with 800cfm Eldelbrock.
Another great video my Edelbrock 2065 dual quad set up arrived 2 weeks ago I ordered it 8 months ago the metering rod's were bouncing at idle 300 duration cam I put in the blue springs and they stay down at idle, I'm sure there is more tuning to be done idles great in gear plugs are tan colored and it's a frickin blast when I put the pedal to the metal in my 68 Camaro good guys in Puyallup is 2 weeks away I'll be there keep the videos coming
Awesome! Hope that event is a good one this year!
So I bought a cheap Amazon kit changed out couple gaskets and I messed with my idle screw once I put it all back together and put it on. I think it’s a really high idle and now I’m getting that ticking noise. Thank you for the clarity love your videos and clear knowledge.
I have a 65' thunderbird with the 390FE. I have the Edelbrock performer intake manifold, lunati camshaft just a bump up from stock cam specs,. shorty headers,.etc... my engine vacuum was 19-20 (green zone on the vac gauge). I called Edelbrock and they told me to put in the silver spring into my 650avs2. Runs fantastic .
What would be best step up springs for 1406 elderbrock on a stock tbi 350 with air gap intake dual exshust timing set at 12degrees
Also have spacer on
@@87olds_rocketboii yah I answered before seeing it.
@@87olds_rocketboii what's the vac gauge reading?
Excellent video as always. Thank you. Your point about timing is very interesting. I am at 5300 feet and when I set the timing to the shop manual specifications, my engine ran terrible. I advanced it and always figured it was because of altitude, despite there being no good references or agreement as to how many degrees you should add per thousand feet of elevation. I can’t remember how many additional degrees I added, but I think I went from something like 5° (spec per the manual) up to about 10 or 12 BTDC. I worried that was quite a bit of advancement. Your comment about today’s fuels was very interesting and something I was unaware of; that may be part of why i had to advance the timing so much. Once I set my timing ( I pretty much just set it to where the engine idles well and does not ping under load), the carburetor was easy to adjust.
At that elevation I start at 14-16. I did a video on tuning for elevation. Gotta have more time to burn when there’s less oxygen and the fuel is absolutely awful!
In my hobbies I look for the Jedi master to teach me. I’ve found you!
My interest in the functionality of the rods and springs is triggered by a horrific discovery on a purchased edelbrock. I wish I could post a photo.
The left cover cannot be opened to remove the rod. Appears fused or god knows.. below that the casing has broken open and I can actually see the top of the piston.
What on earth could have caused such destruction? Guess I’ll be looking for another 600 right?
Hey Boss, love your educational videos, if recall our conversation a couple months ago, installed the in the tank EFI Bosch fuel pump, having 6an fuel lines & Holley regulator for my 91 Jeep YJ with the 383 stroker and the AVS2 500 cfm...Runs absolutely perfect now. Will begin tinkering with the fuel mileage now since the Fast AFR was also installed as well.Keep up the awesome information, it's appreciated. 👍
There’s some small gains that can be made with a good tune. If you’re chasing bigger MPG numbers though, you’ll find those in the transmission. More gears = lower operating rpm and more economy. Sounds like you’ve got a great set up! Dependability is your biggest success with that set up. Keep tuning!
Awesome video man, great information and easy to follow. I’m new to carbs and about to rebuild a 1406 for my 350 k5. Thank you so much for what you do. And for the tip about the 12 degrees before TDC.
For sure timing is what gets everyone at first. It fixes quite a number of their perceived carburetor issues. With todays fuel, 12 is my go to starting point for the elevation I’m located at. Best of luck on your rebuild! Don’t hesitate to let me know if you have any questions. Happy to help if I can.
I saw an advertisement on the internet selling the springs and they are red! I have a suíte case with a calibration kid and I remember that there was no red.But the color of the springs went out...All that was left was the pink.The other collors went out. I'm going to have to put the menhirs in ; I think the blue one is smaller! I have very low vacuum at idle! When I shift into gear to maneuver the engine stalls! Based on your explanation, I will have to put It in blue! What if the blue one doesn't work?? My valvetrain is Crower 292/298 with 107 lobcenter! I bought 0,2mm steel wire to make weaker springs!
@@4100gtb there is no red, unless you’re looking at a counterfeit kit.
Great vid on the step up spring operation as to knowing that the metering rod piston should pop up when you snap on the throttle and that's when you got the right springs in
Tank you! Sou do Brasil, esse vídeo confirmou minha suspeita! Tô com um comando Crower 292/298 no motor GM 250 cid
Em marcha lenta está dando excesso de combustível! Vou colocar molas mais fracas!
@@4100gtb what is your vacuum at idle?
@@MuscleCarSolutions I didn't look até the vacuum gauge, but it's definitily low! Due to the Crower 292/298 command having a center lob of 107.Engine is a 6 cylinder GM 250 Cid!
@@MuscleCarSolutions At idle speed, when I Go to leave the garagem I can't, the engine stalls with todo much fuel
@@MuscleCarSolutions Edelblock 1404!
i am guilty never think about them after they goes in the first time. great tips
It’s for sure an easily overlooked tool that can be used to get the most from an engine!
Great Video, Thanks for taking the time to upload all these Videos.
You’re very welcome! Thanks for watching !
Is there a spring weaker than the blue one in the kit?
I think you said the plain spring releases at 16 in. hg @7:05, I thought it releases @ 8 in. Hg.
I have one sticking in the jet on one side and once engine is up to temp it idles rough and loss of power and when reving it up cold or warm I hear a whistle like a vacuum leak. Sprayed base and nothing leaking. Works great when engine not fully up to temp
i'm going to have to look and see what springs are in mine. I should probably order the kit first. I did add a fuel pressure regulator and gauge. gauge showed 7psi, but regulator is supposedly calibrated to 6.5psi at the factory so i assumed my gauge is 1/2psi high and set it to 6. Before adding the regulator it was showing 7.5psi, so probably a little high for my carb.
Been driving w my 1406 w AFR , Tach and VAC gauge on the dash for almost 3 years now.
Fat old Dodge. Cruise and tow.
Lookin for MPG & Tow power.
Noticed some stuff.
* jet. Jet.
* timed enrichment.
- nothing is perfect. - more of a compromise.
Keep it in the middle AFR - 11.5 to 16 seems to work.
Tuning with the right tools certainly helps. Sounds like you’ve got what you need to make the decisions you want.
Great video, I love it. Question i have a 86 ford bronco 5.8 engine with a brand new AVS2 carb and have a mechanical fuel pump should i changes to a electrical pump. Thanks
That’s going to be a preference choice. I will always prefer to run an electric pump. But I also run mechanical pumps with no issues. Your 86 likely has a return line back to the tank which is good. I’d still add a regulator so you can tell the carb how much pressure you want it to receive.
Excellent stuff, i have an edl on my 1982 Camaro. Putting a edl performer eps on this weekend with a melling mtc1 cam/lifters
Thanks for these videos! I am interested to know if the spring is too soft/firm for my engine what symptoms should I notice? Thanks
Need to break that down into areas of operation. Idle, off idle, cruise, power. If you’re having an issue in one of those areas, then determine if it’s a lean or rich condition. You can then start making adjustments from there. Here’s where an AFR earns it’s money. Takes all the guesswork out of it.
Maybe that would be a good video!
@@jonjacobsen6339 absolutely! We’ll be making that video sometime.
If you will put that distributor on manifold vacuum, it will be a lot more responsive and have more vacuum at Idle. I know that this was only demo purposes but that would be a good video to show people.
@@AdamDixonSR that’s incorrect. It’s not the only or best option 100% of the time. Not sure how that internet fallacy started, but there’s a reason why the two ports exist. All depends on the cam profile and engine set up.
@@MuscleCarSolutions That would make a good video and I believe that you would do a good job explaining it.
Just spent 2 days tuning my buddies 77 351m with an afr and have it dialed except for one specific throttle input cruising slight load and WOT is spot on but i could not fix a rich condition at around 2/3 to 3/4 throttle didnt matter ifbi had the rods set for the leanest setting with the lightest spring it still maxes out the afr at 10 to 1 at that specific spot this is with and edelbrock 1406
Yeah, cool video really really liked it. I got a question. Could the springs make the engine surge just off of idle?
@@ericneering6357 If they’re opening at the incorrect time, yes. What’s your vacuum at idle and what spring do you have in now?
Awsome video.. im hoping you could help me with this. I just bought a new elderbrock 1405 carburetor manual choke 600cfm and im having issues with just off idle like a stumble or a bog and I can't figure it out.. I went from a Quadra jet to elderbrock.. ive checked timing it was a bit low moved it to 12 degrees.. ive installed new fuel filters and a new stock mechanical fuel pump the engine is a stock 350 in a 1976 chevy k20 manual 4 speed. Only other change I have done was a elderbrock intake and headers and also the plate to make it go from spread bore to square bore. Any help would be appreciated im just lost on it..
Hi, i have a tbi 5.7 sbc converted to carb, but i dont know much about setting time correctly on engine, i know there are 3 sets of time but dont know if wprks for stock engines , i have seen that in modified engines, would be great if you record a video explaining all that settings, love your videos by the way, i have learned with them, thanks
@@JoseHernandez-kw6nn I’ll be doing a video on timing hopefully before the end of the year. Thanks!
Your videos have been incredibly helpful. I appreciate all the information!
I’ve just installed a 1406 on my 454. It has greatly reduced my over rich issues at idle and at cruising speed. I am however having an issue with a burble or slight stutter under very lite throttle. As I am just easing through town and it’s almost as if there’s a miss. I have to assume it’s this step up spring and buy this video it sounds as if a slightly lighter spring will help keep the metering rod in the jet well under very light throttle? If I’m understanding this correctly I am probably seeing the metering rod bouncing up and down when I’ve only just come off of idle and the engine is under very little load.
It’s possible. Difficult to know without knowing what your engine vacuum is at that rpm. But springs are very easy to change you and can make some trial and error type adjustments to see if that is the cure.
@@MuscleCarSolutions thanks for the response. I’ve got a tune kit on the way. I’ll get out there and potter with it. Your videos have been a huge help. Thanks a million.
@@Red9GearHeads glad to hear that you have a calibration kit on the way. Best of luck and glad you’ve found the videos useful.
What about adding a 1" spacer to help with heat soaking? Will you need to make any adjustments? If so, what does it affect after the existing set up? Thanks
Yes to adding a heat blocking spacer. No, you won’t need to make any major adjustments. Unless you’re data logging and have that to work from. Seat of the pants you’re not going to feel much. In most instances anyway.
I have an old school sbc350, I installed a new cam and intake manifold it runs good but when reading the plugs it looks way too lean, which spring will richen up my avs2 650 carb. Thanks. Phil
Great video Good information i a question when im driving around 30mph and step on the Accelerator
It hesitates ?Then takes off is that timing or Carburetor adjustment
Could be both. What carburetor? What is your timing set to (initial and all in)? What adjustments have you made to address the issue?
I set the timing at 12.
32 all 600cfm elderbrock 5.7 chevy it's 1995 motor
@@timothycorya1536 so you’ve got a good start. I’m going to assume you haven’t done any tuning. First thing to do is verify if it’s a lean or rich condition. Move the accelerator pump rod up to the top hole (closest to the pivot point). Does it get better or worse? Try to keep an eye on the rpm this occurs if your problem still exists.
i have a 1983 monte carlo v6 3.7 dual jet edle carb i did a replacement the other one was broken but now i have high idle any tips to fix this i watched a few of your other videos on some good info but wondering if theres any other tips and tricks ? the old carb made it stall when switching gears to drive and reverse the new one just has a high idle idk exactly whats up
I really appreciate how thorough your videos are , truly , I'm having an issue with a 1406 right now and could use some help. I have great responce from throttle , starts great , but runs rich , I've adjusted the idle circut out a bit due to running rich, adjusted idle mixture , timing ect
Nothing helping , the electric choke is not connected to any voltage. Running rich , and spuratically runs fast then drops to almost stall , takes a bit of feathering on throttle to keep it going. Then all is good. Makes no sence to me. 15 vacuum and 5 psi fuel. Any help in the right direction would be great . I really cant see the choke not being hooked up doing this but hell , maybe
@@mikealdag7309 it’s running this way at idle? 100% yes hook up the electric choke and adjust it. What is your initial timing set at?
The electric choke on these carbs will stay closed when no voltage is present, which would make it run rich all the time
With regard to removing the spring/piston/rod and just running on the jet, besides running extra rich and being unable to install a sufficiently small jet, you'd be creating an internal vacuum leak since the piston is no longer there. Sure, the piston doesn't have rings and doesn't really "seal" to its bore, but it does provide an impingement. After all, if it didn't, it wouldn't be pulled down by vacuum in the first place. I suppose the piston could be installed by itself, but that would do nothing for the rich mixture.
Have a 1934 outlaw, timing is good. Have a 650 edlelbrock when I’m cruising it’s fine when I punch it , it bogs and falls on its face. 383 stroker mild cam . Any help would be appreciated I follow and trust your videos thanks for taking time to put them out there.
@@stillwaternyc9707 gotta know the details and I’ve got a bunch of questions! What’s your initial and all in time set at? Can you share the cam specs? What have you done so far to tune the carb? Do you have a calibration kit? What is your vacuum at idle and what step up spring did you use?
My Chevy 350 with the edelbrock 1406 bogs pretty hard when I floor it at low rpm. Rolling above 2500 rpm or so it seems to take off fine. Would I go down to the yellow step up springs or up from the stock orange springs in there now?
I have a similar issue that I think is carb calibration related. Did you figure out what you needed to do?
@@302fordtrck I changed the step up springs and it worked
@@jakeopperud3700 what spring did you put in. I have same issue with mine
my 454 runs 21 vacuum at idle, I run a 800cfm AVS2 and edelbrock 1722 fuel pump (brand new saddle gas tanks and tank switch) on it. Its pretty much all stock rv cam stuff as far as i can tell, with peanut port heads. I run at total of 35 advance without va and using a reliable digital timing light, I am using manifold vacuum for VA, I cant remember the jet sizes but I am pretty sure i left them stock when I bought it, and I confirmed float levels are good. I sometimes deal with a bog from part throttle to wot at around 2k-2,500k rpm, that is around 45-50mph at part throttle to wot when it happens. It starts missing and jerking, losing power feeling like its about to die but not a solid bog but like trying to go more but getting hit with bog real quick over and over. Its very hard to explain, but I am curios what would you do in my situation? I thought to check the boots on the dizzy too make sure there is good contact, but any suggestions for spring size (i run orange atm) would be appreciated.
You’ve got a couple things there that are fighting each other. First, 35 all in timing is likely ok. What’s your initial? Why are you running on full manifold vacuum? That advance you’re getting at idle and off idle aren’t really necessary with a stock type cam and engine. I’d be willing to sacrifice some of that vacuum. 21 is great, but when you start tuning it’s ok to lose a little bit of that to gain back some power down low. You can pop in the silver spring to start. Then start tuning. You can even back the accelerator pump position down to the middle to see if it makes it worse or better. You might be getting a bit too much fuel. That and the spring change will help you confirm that. One adjustment at a time to see if you’re on the right path.
@@MuscleCarSolutions The initial timing fell at 14 to make a total of 35 at 3500rpm (it did not advance any further past that i confirmed) with va unplugged and capped. I switched to manifold because response feels much snappier off idle and my understanding is Ported was just an after thought pushed by the EPA to make your exhaust run hotter and burn more biproducts in the emissions. Everything feels great besides the occasional crazy stumble/bog i get at mid throttle to wot. When i use VA ported i idle at 14 degrees, with manifold i am idling at 34 which is too be expected with the extra vacuum, which means my canister is giving 20 degrees advance at full manifold vacuum, i may check if its adjustable but i feel like this is not that issue as it happened before i used manifold. Honestly the Manifold is supposed to keep your engine cooler at idle and i will say its much smoother from idle to wot, i can easly spin the tires there its just under partial load at part throttle to wot it starts doing the bog/stumble shit.
@@stormwolfgames6636 I would check your fuel pressure and check the float drop and float height to make make sure they are in spec because it sounds like your running out of fuel in that mid to high wot . Make sure to run a phenolic heat spacer between the carb and intake so the fuel stays cool and doesn't cause issues of boil over and flooding or vapor locking which can happen especially with the fuel we have that has alcohol in it . If possible run a 3/8 ths fuel line from the tank to the carburetor to make sure it's getting enough fuel and try to run at least 1 fuel filter but I usually run 2 ! 1 before the fuel pump and 1 after to keep any crud from going through the pump and into the the secondary fuel filter and I've noticed as of late that these cheap plastic fuel filters now don't filter very good at all so stay away from them if possible and try to use the metal filters that are used for fuel injection instead because they filter down to much smaller micron particles so the injectors don't get plugged up plus the plastic fuel filters now are so cheap you can actually see them pulsate from the fuel pressure which could possibly cause a failure of the filter cracking open and leaking fuel on a hot engine or surface . Fuel pressure should definitely be check out and set with a fuel pump regulator so it stays consistent because too much and you start pushing the needles open off the seats and cause a rich condition and flooding and too much fuel can actually cause fuel wash in the cylinders where the fuel is actually washing the oil off the cylinder walls which can hurt the honing marks in the cylinders and eventually the rings won't seal correctly and compression will drop because of this especially if it's way over jetted . I'm on here because it popped up on my TH-cam feed and decided to watch this because I have run these carburetors on many different engines through the years and usually they are a pretty good carburetor and are a ok street carburetor but for racing I would rather use the older Holley double pumpers or even that new Edelbrock Brawler that's out that is basically Edelbrock's version of a Holley that I hear are good .
@@peteloomis8456 So I actually just bought a heat shield spacer gasket from edelbrock, gonna give it try because when the weather was a little warmer i think i was having some vapor lock issues since i am using a 2 port fuel pump now instead of the old 3 (In, Out and the Return line!). I would rather run the return line as it was designed to avoid these issues and keep the fuel cool, but there is no fuel pump designed for a big block that does not at least get a little bent at the nipple because the can is a bit too long for a bbc swapped into a 1/2 frame. I mean it worked for awhile like that, but it always bothered me the main in line i believe gets bent a bit by the crossmember. Anyways so thats why i havent been using the return line, which is why my first guess after spark (which i triple checked and is good) was overheating fuel. I noticed when i had my wife pump the gas with the truck off so i could confirm throttle plates are opening all the way, after running it to op temp and around the block, the gas was evaporating as soon as the booster poured it in because the carb was getting so heat soaked. I am guessing that is what is happening in this wot moments when the engine is getting its hottest the carb is just absorbing all that heat and the fuel is just evaporating and causing a percolated situation i guess. I will install this heat shield gasket and let you know what my results are.
If you put a step up spring that is stronger do you have to but the accelerator pump back to where you moved it from mine was in the 2nd hole and I put it in the bottom one and I put step spring in the one after 5hg
Those adjustments are never permanent when tuning. So yes try it as you work through the process and see if it makes it better, worse, same. Don’t forget to keep working timing as you go through this is changes.
Ok thank you like your videos to
What size meter rod would you use on a 496 stroker motor 800CFM ... I put in the plain step up springs but never changed the meter rods ..I'm reading 16 vac
Don’t just randomly change rods or jets. Follow the tuning chart. It will lead you in the right direction. Just determine if you want to add more fuel or take it away.
are these springs ok to use on quadrajet carbs that you know of?
its nice that they are labeled
if an engine has 14 inches of vacuum in your experience what spring would you recommend?
i have a question for you! i have my cruise and idle mixture about perfect as well as timing set. super crisp throttle response and wide open throttle response feeling great! i have a 1986 suburban big lift 35" tires with 4.88 gears, powered by a 383 stroker (ATK HP33) with a 650cfm avs 2 paired with a 700r4 if i am at cruising speeds and roll into the throttle under load eventually the afr goes stark rich 10.0 flat same thing happens when in overdrive and climb a grade vacuum drops to near zero and afr goes full rich even when secondaries have not opened. i have been through multiple jet and metering rod changes and best i can get is 10.5-10.7afr why am i getting this rich under load if all my other afr's are good around town/idle and even wide open throttle? what can i do? thank you for all your videos please keep up with all the awesome information
What is your timing set to? Initial and all in? What step up springs are you using? What number on the calibration chart are you on?
@@MuscleCarSolutions initial timing set at 16 degrees and 35 all in. I am running the “progression ignition” hei distributor and have played with timing with little to no change. I am on #10 with 68-47 rod pink spring also running the 800cfm accelerator pump and 33 nozzle . I am at 2200 elevation
got a 1404 on a 302. problem I'm having is the metering rods, both of them, are getting stuck down when engine is running no mater how much I push the acceleration, but will pop up when engine shuts off. any suggestions for this?
@@dennissteege the engine vacuum holds the rods down until load is applied and vacuum drops. They should be fully down at idle. You’re not metering fuel through the main metering circuit at that point. There is no suggestions. It’s operating as it should! Follow the step up spring tips in this video and keep them in mind as you work through the tuning process.
Hi, I have an sbc with a 671 blower what spring would you recommend I start with?
Having issue with my 1406, no matter which springs I use for power adjustment, the vacuum pulls the metering rod down but the drop in vacuum does not occur when increasing rpms or goosing the engine. Tried all the different springs with no change.
Have you driven the vehicle with the spring rate you choose based on the engine manifold vacuum at idle? What is that measurement?
@@MuscleCarSolutions Thanks for reply, love your videos. Since sending my question, I changed only the metering rod to a 70x37. It seems the stock rod was not releasing. I also had to put a #8 spring in to make it work. So now I'm in the process of installing an AFR meter to tune the carb. Wondering if you have a suggestion on AFR reading. Towing 3000 lb travel trailer. Truck if chev 350 with RV cam and 373 gears, 2 wheel drive?
Ok. Well on AFR you’ll generally like to see 13.5. If you get to 14.0, it’s starting to get a little lean.
@@MuscleCarSolutions Thanks, I was thinking around 14.0, I will see how the tuning goes
@@MuscleCarSolutions Another question, waiting on calibration kit to arrive, borrowed a kit to troubleshoot, so the plunger bounces with the 70x39 metering rod and stock `.098 jet and #8 spring. Regarding the primary circuit what do you recommend the tuning steps using AFR? Also should I be making any changes on the secondary jets which are stock .095
Every time i have to drive up a hill and there is a stop sign had to stop and when i try to go my engine feels like wants to die i need to put a bigger spring or smaller spring i have a 350 engine and avs 2 edelbrok carb???
Great video and explanations!
I got an afr gauge my idea is very close but when rpm goes up I’m getting a rich reading will a spring change fix this or is a jet size required? The gauge reading is around 11-12
Had pink spring in and they stay down even when I goose throttle I have 11-12 vacuum on gauge thinking silver spring might be better what do you think
Pink spring is rated at 7” (14” of engine vacuum). Orange spring (5”, 10” of engine vacuum) better matches that situation.
What spring would you recommend if 350 small block runs rich. Has mild cam and timing is correct, pulling 12 on carb vaccum. Spark plugs wet and smell like gas. Any suggestions would be greatly appreciated.
@@nursecuenca what is the timing set at? What are the specs on the cam? Are you checking full manifold vacuum to get that low reading of 12?
@MuscleCarSolutions yes its 12 on full manifold vaccum. Engine timing is set 12 degrees before tdc on idle. I don't have information on mild cam. If I remember correctly it's at 35 degrees at 3000 rpm.
@@nursecuenca if you can only muster 12” of vacuum, that’s generally due to a fairly radical cam. Unless you have some other issues. What step up springs did you put in?
@MuscleCarSolutions It has original spring that came with carb. Just wondering what spring size/color to use in order to lean mixture. I'm new to classic cars and have learned so much from your channel and your knowledge
@@nursecuenca hard to say. If you haven’t bought a calibration kit, you’ll need one. It comes with all the springs. The tuning chart has the spring color and it’s corresponding vacuum rating. If you’re at 12, the stock spring in an Edelbrock carb is the orange spring, rated at 5”. If it’s released and flowing fuel too early, then drop down to the yellow spring. That will open later as the vacuum will need to drop below 8” of engine vacuum to engage. But there’s other things here you need to verify first. Fuel system set up. Run a regulator at set at 6psi. I don’t know your elevation to know if 12 advance is enough. I did videos on both of those topics. Before you start making carburetor changes, you have to set the fuel and ignition systems up for success. If you don’t, there is little to no tuning that can be done.
I have a 1970 Impala with a modified 350. 10.25 compression, aluminum heads, comp cam 530 lift 280 duration and an Edelbrock street performer carb. Runs good until the engine gets completely at operating temperature then it stumbles a little as I slowly accelerate. I have a AFR gauge installed and the ratio when it’s doing this jumps around 15-16. All else it runs a good 12-13. Accelerator pump is in the richest hole. Stock meter springs are installed. Any ideas? Thanks for your great videos!
What rpm is this occurring? The accelerator pump shot is a short window/amount of operation. Depending on when you’re experiencing this, it’s a power or cruise mode change. You’re very smart in using the AFR. Now you know which way to go in the tuning chart! This video will help you dial in the step up springs.
@@MuscleCarSolutions
I’ll pay attention to the rpm. Additional I do have pre and post electric pump filters (100/10). The carb is stock except the accelerated pump being in the closest hole to the pivot point. Revs like a race car but just has that little hesitation hot. I have a metal carb plate between air gap intake and carb. Thanks for your quick reply!
@@blessedlife1039 ah. Well you’re ready to start tuning! Also the metal spacer is problematic if you’ve seen my videos on heat soak. Spacer isn’t a bad idea and using a phenolic plastic or wood laminate spacer will help keep the carb cooler. You’ve got the right filtration set up. Got everyone lined up for a easy tune!
I used your videos extensively to set up a 350 SBC with a 1411. While this is not ideal, I did not want to buy a new carb since the 72 Blazer will be getting a gen V L8t motor soon. The 1411 was on the Blazer when I bought it. It now runs pretty good and my AFR gauge reads about where I am happy. It took a while to find the right combo but I am feeling good about it. 104main jet/100 secondary, 68x47 rod and plain spring
The AFR is an amazing tool to help the engine be happy. Smart decision!
On that carb one one is for GM vacuum while idle the other one there is no vacuum at idle for AMC , Chrysler and ford. The tube needs to be on the driver-side line , after timing with out vacuum.
I put in a avs2 800 cfm and went to change the spring and rod today. The driver side came out with ease. The passenger side is stuck I can get it out about halfway and it binds onto something. Also doesn’t move freely like the drivers side does and seems to keep getting hung up on something in there…..is this carb a dud? Ever come across this issue?
@@gurtajdhillon23 nope. The avs2 is always a little more tight with the air valve secondary tower taller and a little more restrictive. Take it off the engine if need be and completely remove the piston cover if necessary. Unless the rod is bent, then pop the airhorn assembly off and you’ll know instantly if that’s the case.
@@MuscleCarSolutions will do! Thank you again for your help greatly appreciated.
love you videos. Couple questions, when does cruise mode stop and power mode begin? Is that based on stepup spring vacuum rating? Should the secondary flapper thingie be adjusted so it opens when the step up spring pushes the rod up? Your tank, filter, pump, filter, regulator, carb drawing is missing the fuel pressure gauge :)
I suppose that’s the trouble with trying to be helpful with these videos. Someone always has to nitpick. 😆
Great video
Thanks for the education
THANK YOU
I have a problem that i cant figure out how too solve. My engine have around 14hg vacuum at idle. But when i put it in drive the vacuum drops to 12. So need 5hg step up spring to hold it don at idle. But with 5hg spring its lean at power mode. Have at about 15hg vacuum att light throttle(power mode). What can i do to fix this ?
Couple questions! How do you know it’s a lean condition? What is your initial and all in advance set to?
Im new to the old school scene and need some help on what spring you think i should use, im still a bit confused cuz im so new with this stuff. I got a vega with a 327 with some old double hump heads, medium cam, a performer intake and now the avs2 650.. did the timing by ear and tuned the carb by ear and feel, it ran great and strong for months but now fouls plugs and always seems to run rich and was just hesitant off a red light and stumbled and also stumbled full throttle when the secondaries kicked in i think... the step up springs are factory never touched em and never touched the secondary throttle blade tensioner screw either.. any help will be greatly appreciated
Ok first, there is no tuning by “ear”. Get a timing light on it. Depending on your elevation, 12-18 initial. Get a vacuum gauge on it. Find your full manifold vacuum at idle. That will help you make your initial spring choice. That can change later as you continue tuning so be prepared to make some adjustments of when you want the fuel introduced. Get a calibration kit. The 650 is a lot of CFM for that engine. Without knowing any specs on the cam, it’s practically impossible to decide on the right CFM that engine needs. But to you’ve already made a choice, then you’ll just have to do the best you can to get it dialed in. Get a pressure regulator and gauge. Regulator is the last thing in the fuel system before the carb. Set at 6psi and you can adjust down as low as 4.5psi. Downer matter of you have a stock pump. Get the regulator and give yourself that ability to adjust. I did a separate video on how to adjust the AVS. That will help you understand which way to go and WHY. No need to be frustrated. You just haven’t started tuning yet.
@@MuscleCarSolutions thank you, really appreciate the help. I'll go off of this reply and try to get it dialed in the best I can. Thanks again 👍 I'll check out your other vid on the avs as well
@@JoJo-209- yup. Don’t hesitate to ask and questions as you go. Once you start getting it more dialed in, the more you’ll love it. Have fun!
I just ordered an AVS 2 for my 62 tbird with a 390
Fun! One of my favorite carburetors! How’s the VRS treating you so far?
Hey Buddy I'm back to let you know what I have found out...I bought a vacuum gauge and followed your instructions but just wanted to ask you to weigh-in on what I have found... at 1 1-2 turns (factory setting) A/F ..I barely made 5 inches of vacuum but screwed the A/F all the way in and I could almost get 9in, but really I should say 8.5 to 9 and it bogged down when I screwed out I havnt adjusted the floats but I did get a air chuck with a rubber tip and blew each side out on the af and checked the tapered tips( clean,no ridge).....my ignition is a MSD Digital digital 6al MSD Pro-Billet Dis. and a Blaster 2 coil. I should mention I gapped my plugs .45 thousand...but I'm smelling gas in the exhaust and l have the Accelerator Pump in the middle hole....What Step-up should I run?, MY last plugs were heavy carbon fouled with white electrodes and a rusty red color at 2,000 miles meaning what? Timing is at 35 and I have my vacuum secondary hooked up to the drivers side port of the AVS2 the engine is 2,000 miles old completely new...I can't tell you how much I appreciate your help and time your an invaluable resource
You’ll have to remind me what the situation you’re working with. Assuming you have an aggressive cam with that low vacuum. Is your timing locked out?
@@MuscleCarSolutions No sir, At 2500 aprx I am 35 degrees and my cam is a 226/236 589/589 110+4adv@50 but with 1.5 RR it's 540 lift? I set my timing with the vacuum advance plugged
@@richardclary6267 ok so what’s your idle rpm? If it’s more than 1000, then we need to try and get it back under that to get it out of the transfer slot. Something is pulling too much fuel. You can try dialing back the fuel pressure a little but on that cam I wouldn’t go too far with it. It’ll let you know if it doesn’t like it. Getting the idle under control would be a good place to start. Assuming you mean your vacuum advance hooked up to the full manifold vacuum. Might give it a go in the ported side. Check your initial timing again. If it’s under 12 you can add more and see if it helps with the idle control and the rich condition. Not sure what your elevation is but again when you get to an area it doesn’t like, it will tell you with hard starting and some detonation. I’d begin there first and you can build on the step up springs from there. That way you can verify engine vacuum at its best scenario instead of chasing things aggressively back and forth if you make a big spring change based on what your idle vacuum is right now.
@@MuscleCarSolutions idle rpm is from 500-650 its not steady because of the lope..ok so yesterday I noticed that my Holley 110gph fuel pump was on 8 I backed it off to 6 1/4 psi (rock solid no needle movement) ill se if i can find out how to lock out the distributor and I am going this evening to but new carburetor gaskets my old ones were fine, but I'll buy new ones anyway, I'll check my timing ASAP and let you know initial and I'll change to port (drivers side) Buddy is it possible the 650 is too small Edelbrock puts the 800cfm on these motors as 350's why? Also I put the Yellow springs in? Thanks
@@MuscleCarSolutions also in in Tupelo, Mississippi so 279ft above sea level
I'm running a Carter 9635 on a mild 302 that I'm having trouble tuning a horrible WOT bog out of, I may have to play with the springs after finding out how much vacuum I'm pulling. It's bad enough that the car has stalled trying to go wide open. Changing the position of the pump rod has made absolutely no difference. Idles just fine, seems to be ok if I roll into it, just WOT giving me issues.
When you say mild, do you mean stock? Cam change? What specs? Intake? Headers? Are you sure that’s the right size carburetor for your application?
@@MuscleCarSolutions Sorry, I wasn't very specific. .030 over, Summit cam 216/216 @ 050, .485 lift 110 LSA, Chinese Edelbrock knockoff intake, headers, some basic port work on the heads, 58cc chamber factory heads. 625 could be a little on the big side I guess, but I do have a 500 cfm Edelbrock that I could throw on and try.
Not a mild cam, not really aggressive either. You’re kind of in a gray area there. I’d concentrate on either tuning the carb that’s on it now, or switch to the 500 and tune it. Just as a wild guess, but I think you’ll find better luck with the 500. Certainly better throttle response and easier to tune for that cam profile. Get a calibration kit, make sure your timing is set (12-14 initial and 32-36 all in), fuel system is up for the job (regulator and a gauge would be a must for either carb choice), and see what you can work our.
Where would be the best place to get a set of springs for a EdelBrock 1406 going on a 302 ford motor? Motor is NOT stock cam wise, rather bigger cam. but im wanting to learn this so I know everything about this carb I can know
Buy the calibration kit for the carburetor. It will include all the springs.
I would love to hear a carb tun for 2x 500 AVS2 on a tunnel ram small bock chevy
@@mikemcardle8159 I may end up doing that but it would be quite awhile down the road. I have all the parts to do it, just not enough time!
I have 22 inches of vacuum at idle. What spring should I use?
Plain - silver.
Found this after the sec tuning vid... to continue ...my 283 is .030 over, heads shaved .003 for trueness, as i said in other vid comments i have a rare 2 yr made gm 327 intake on it. Vac was running right at 20 but since then and only less than 400 miles on it, its broken in some and i took a little timing out of it. What springs should i be using. Havent been in the piston springs yet to see, if orange is stock then ill assume thats whats in it.
@@charlespartak2435 hard to say with the limited information, but assuming you’re close to sea level and your timing is around 12-16 initial and you’re getting that 20 inches of vacuum at idle, then run the silver-plain springs.
@@MuscleCarSolutions 1300 ft ASL.
Today I installed a 1906 650 CFM electric choke on my 383 engine. Borrowed an AFR gauge from a friend and ran the engine just as it came out of the box except setting the idle speed and AFR. On my test drive I get a very lean reading on light to medium acceleration like high 15 to low 16 but on cruising at 55mph at 2000 rpm I am reading high 12 to low 13. Everything I see on the chart I see that if I do a change on one it makes the other worse. I have not changed anything yet, just wanted your input on this one. I was thinking maybe a softer spring? My vacuum is around 14 in park and 12 in gear holding the brake. Your thoughts would be greatly appreciated. Also btw I really like your videos. They help me a lot or at least give me a lot of ideas which might be scary :)
@@andyspence4014 absolutely set the springs first. Right now you don’t have enough good info coming from the carb to make any rod and jet changes. Make the spring adjustment first, then verify the accelerator pump shot and then you’re ready to start making changes based on the tuning chart. Good move using the AFR. It will dramatically reduce your tuning time. But beware! You may come back to springs again as you work through the process if you need to change opening events.
How many pounds does the red spring have?
@@4100gtb there is no red spring.
just put a 1407 750 on a 396 with a cam that has 6-7 vacuum at idle. It's a bit rich at idle so after watching this I'm thinking I'll try lighter springs and possibly a metering rod change depending on how that goes. Thanks!
Why so low on the vacuum? Extremely aggressive cam?
@@MuscleCarSolutions yeah friend bought the wrong cam and heads lol. I'm just helping him out. He also had Fitech which was awful so I removed that and put on an edlebrock with aeromotive dual fpr setup
What should timing be set at for modern fuel
What engine? What altitude? Any power adders?
@@MuscleCarSolutions stock 350 with a 1405
@@oldchevy5512 well, you didn’t mention what elevation you’re at but here at a little over sea level, I generally start at 12-14 for initial. Higher elevation will change that starting point.
Thanks wasn't sure on elevation I guess more or less I swaped from tbi to carb runs good but it starts dieseling when turned off but thanks for the info
Excellent video!!
Glad you enjoyed it.
@MuscleCarSolutions I would really like to see a video with a vehicle that stumbles off idle when you floor it but runs great off idle.
I would like to see the steps you take to tune the stumble out of the vehicle right at the start as you floor it off the line.
@@johnnyturbo8460 one of these days. I’ve got a number of tuning videos I want to do. Need more time to make it happen.
@@MuscleCarSolutions sounds good 👍
Always Great videos!! Thanks
Thank you sir!
Only problem that I have had with springs is edelbrock paints the orange spring yellow and the yellow spring is an orangey copper color, why not use 4 colors that aren't close in color?
Don’t know that I’ve experienced orange springs that were painted yellow.
@@MuscleCarSolutions that's what I got when I bought just step up springs because some of the springs I got in a tuning kit were damaged.
Awesome stuff U share! Thanks
You’re welcome buddy! Hope all is well in your world!
@@MuscleCarSolutions all good
My carb seems to be rich at idle how can this be resolved
I did a video on how to set idle mixture. There is that and all the other things you can work though to get where you want it to be.
The rod piston keeps on getting stuck idont know why
Thanks..
Sure!
Excellent!
Thanks!
Ok fine, I'll order the kit.
Step up springs are one of the best tuning points on an Edelbrock carb. Have fun!
@MuscleCarSolutions i think its sucking too much gas and i should at least look into this
@@imheretolearn770 follow the video and how to set them and you’ll quickly know if you’re on the right path of not.
@@MuscleCarSolutions Thank you.
how could it be rich with no spring the rods never rise with no springs I don't get it
Edelbrock instruction book says plug into manifold vacuum, I see your in ported vacuum, also I see you have an adjustable vacuum advance and the instructions on an Accell vacuum advance also say to go to manifold vacuum.
I’ve always run ported on mild street engines. Best way to get the full range of timing and there’s zero reason to run full manifold vacuum when it’s not needed. The Edelbrock instructions suggest full manifold vacuum with aggressive, long duration cams which this engine doesn’t have.
20 in/hg × .491=9.82
14.7 -9.8 ≠ 4.9
in/hg to psi
Can u tune my truck?
Watch the videos. You can tune it yourself!
I swear I have spent more time and money than what the carbs cost new . And still not right. . Must be why there are so many Edelbrock factory refurbished carbs for available.
@@GregBallard-e1p literally the easiest carbs to work on and adjust with the tuning chart. Get the fuel system right. Put some timing into it. Follow the tuning chart. Extremely simple if you follow that recipe.
They are simple to work on yes , but with two 600cfm's . Along with a 246 dur 596 lift 110 sep cam . 8" vacuum . . Timing 18 deg initial 18 deg mech all in 2800rpm I need more than the idle cruise , power mode and step up adjustments that are available. In reality I am looking for perfection , when there is no such thing.
She seems she runs a bit rough..
She was for sure with the wrong springs in!