Easy DIY Performance Re-Curve: '57-87 Ford V8 Distributors - Tune Your Ignition Timing
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- เผยแพร่เมื่อ 1 เม.ย. 2022
- Everything you need to know to re-curve your 1957-1987 Ford V8 single point, dual point, or Duraspark distributor’s mechanical and vacuum advance mechanism.
Tuning your ignition timing is critical to how your engine operates. You don’t need to spend hundreds of dollars on an aftermarket distributor or programmable ignition box to be able to adjust the timing curve your engine needs to provide maximum performance, optimum fuel efficiency, and cooler engine operation.
In this video I get into detail to cover the entire process to turn your stock distributor into a modern performance distributor. Topics include:
Cap & Rotor selection and why the Duraspark cap is preferable for performance ignition systems.
Changing and adjusting the advance springs to change the rate of advance, and the effects of modifying the advance mechanism weights.
How to modify the advance limiter WITH MEASUREMENTS to achieve the desired advance curve, and the importance of the advance limiter bumper including what happens if it is damaged or missing.
The importance of Vacuum Advance and how to adjust it.
A companion video will follow soon to show the full process of determining and documenting your current timing curve, assessing your engine’s ignition timing requirements, and then developing a new ignition curve. I’ll explain the proper operation and benefit of vacuum advance like how it improves fuel economy and reduces engine operating temperatures, while still allowing maximum performance.
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#shelby #mustang #gt350 #ford #289hipo #restoration #performance #modification #distributor #duraspark #dualpoint #timing #ignition #autolite #motorcraft - ยานยนต์และพาหนะ
Informative as always! I remember you explaining a lot of this when I first brought my car up to you. Would have taken me years to figure out the advance springs were the wrong size in my distributor, which was supposedly rebuilt and recurved. Nice work Walter
Dude u r the man thanks for all the tips and tricks. Just subscribed!
Great Info as I am restoring my Dad's Bronco :-)
This video seemed like it was going to be really long when I started it, but there's a huge amount of information here that you won't necessarily find elsewhere in one place. Great video.
Thanks!
Awesome video and very informative!
Thanks!
Really enjoyed your content!
If you have a clearance problem and cant use the big ass 2 piece cap but want to use 8mm wires with female on both ends , get a cap for a International V8 80 and newer is what ya need. If ya wanna use the big 2 piece but don't want your wires crossing over , meaning you got 1,2,3 and four coming out the right side of the cap and 5 6 7 and 8 going left , get a cap , rotor and adaptor from a late 80s early 90s EEC4 with a two-level rotor and two-level cap , and I'm pretty sure they use a different adapter. They are really weird looking on the inside but the firing order is cast into the cap and it looks really cool having the plug wires really neat aiming right at the cylinder and no excessive wire twisting around looking messy and tangled. They only made them a few years and once you see one , it will stick out like a soar thumb viewed from the bottom. If your gonna buy one to covert to duraspark and female 8mm wires, might as well get the weird one. You will freak your friends out when you show them. One caution, some used a rotor with a wire clip on it, don't use that one or you will need a different shaft for the rotor to sit on.
I'm a GM Delco guy , my Pontiac is recurved for the old gas. I'll need to do some different things but I get the idea. I really like your channel Walter. Thank you for sharing your knowledge with your very informative videos.
Timing is timing. It really doesn’t matter if it’s AMC, Ford, GM, or Mopar. For modern fuel, it burns faster, you need a little less timing. The energy content is still there so you can still make great power. The key is to have full advance 200-500rpm above your typical steady state cruise rpm, and use vacuum advance on manifold vacuum so it becomes load dependent. Tune for torque and horsepower using the mechanical advance and use vacuum advance for lower emissions, stable idle quality, and cooler operating temperatures. Those principles work on on nearly all engines in older vehicles.
Thank you for the Tip of marking lower part of the cap.
Always turn the Engine further back and then forward and set the timing to the desired degree’s. Remove the Rotor and turn the distributor until it reluctor is in line with the metall part of the magnetic pickup. I guarantee that your timing is already within one or two degrees.
great vid, very thorough.
Was doing this back in the early seventies except I eliminated the vacuum advance and went full mechanical advance with excellent results...
With modern fuel we need the vacuum advance for lean operation so we can manage temps. Mechanical only is far too inflexible for proper operation.
Pardon my french but
Damn good video Sir.
Your right about the gas quality of today vs the 70s gas, if everything is ok to Perfecto !! It won't run worth a $&+- if the timing curve, stability (bushings etc) coil and pickups/points isn't up to snuff the engine will run poorly !! I've seen people literally rebuild the engine that was tip top because of a distributor/ control module problem, the total advance and all in by ? RPM makes a major difference in driveability Performance, economy.
All the best to you and yours Sir.
I've been doing a lot of trial and error tuning in my 429 Autolite distributor for my 70 Torino GT... I must say man what a great vid! You nailed it every step of the way and by far best Ford distributor tuning video on YT... Subscribed!
Right on! Glad the content helped. If you have questions about specifics for the 385 Series, I’ve built versions from basic 429 Thunder-Jets to Super Cobra Jets and displacements up to 604” and installed them in applications ranging from boats, to RVs, Land Speed cars, drag car, and daily drivers.
Very informative 👏 👌 im gonna have to pick your brain sometime. I have an old 289 think 66 ive been slowly decifering
I’m rather fond of 289s. They are great engines. Everyone wants 331/347/363 8.2” deck engines because they are convinced displacement is always the solution. The reality is a 289 has some tremendous potential and the engineering side of a 289 is excellent.
I sent you an email as I could not figure out how to send a picture over TH-cam. Thanks for the great content!
Hi I know this is an old post but thank you !!!!!
Excellent!!!!!
If you really want accurate recurving, you need a Sun Distributor tester. You can see and adjust mechanical and vacuum advance, set your points and test your condenser. There is also an adapter for electronic ignition, and a flathead dizzy adapter.
Absolutely unnecessary to have a distributor machine to get an accurate curve. All you need is a tachometer, timing light, and vacuum gauge, and the entire process can be done on car.
@@TheGT350Garage Im' not saying you can't do it without a dizzy tester, Im' just saying it's more convenient and more accurate to do so. And it takes less time and test driving. You can't flash a timing light on your pulley while driving, can you? ;-)
How is it more convenient to remove your distributor and have to find someone with a machine? And the accuracy of the machine is no better than the accuracy of any good timing light. Any issues that will occur doing the curve work in the car will occur with a distributor that was curved on a machine. And you’re clearly not grasping that the mechanical advance is RPM based, not engine load based, meaning a stationary rpm step test that takes about a minute to perform is perfectly accurate and safe. You test idle timing then 250rpm increments from 1000 to 2000, and 500rpm increments from 2000 to 4000rpm. If the timing is still advancing at 4000rpm you can test at 4500 or 5000rpm to verify but that’s only done to identify springs that are far too stiff. The actual test takes less than 90 seconds to collect all the before data, and the same time to verify the after curve. If you think the car has to be driving to verify the correct timing you are missing the connection that the engine is simply doing the same job as the distributor machine in your garage or driveway.
Have you done a video on what the rest of your ignition looks like? That’s with the duraspark diz.
Very informative. One of the better videos I've seen as you dove into the distributor. I'm helping tune a "73 531C 2V with FMX trans. Pretty much stock vehicle intended to be a daily driver. I rebuilt carb with only one mistake. I used the rebuild kit's power valve of 7.5. Fixed that. The distributor was replaced at some point and now has electronic ignition. Our problem: Emissions tag of 6º is too low. Set at 12º initial but she likes closer to 16. Centrifugal adds 14, 22, and 26º at 1500, 2200, and 2500 RPM respectively. Vacuum adds 2, 14, 18, and 20º when hand pumped to 5, 10, 15, and 20 Hg. I'm keeping at 12 initial only because I think total advance is too high. Using ported vacuum. Your video will help me make adjustments but it would be easier if I had target numbers to pursue. I'm not skilled enough to tune by ear. I have an adjustable timing light and a vacuum gauge. Just need some specs to chase down to establish a curve.
The 73 351C 2V is an open chamber head and that engine is barely 8:1 compression. It will want 16-18° initial and the mechanical advance needs to be limited to add 20° (10L on the mechanism) which will give you 36-38° total timing. The vacuum advance needs to run off of manifold vacuum and is there to enhance light load operation and cruising, you may want to try adjusting the vacuum advance to produce 12-14° maximum at the engines peak available vacuum from idle or cruise speeds. You’ll also want to eliminate any thermal ported vacuum switches from the vacuum advance connection.
I have one more follow up question based on your feedback. Really appreciate it by the way. If I am switching from zero ported vacuum at idle and increasing to 6-7 inches from manifold at idle, does my target initial timing include vacuum advance?
So, let’s start with why ported vacuum is problematic, it gives no benefit at idle or light throttle when the engine actually needs the extra advance to get combustion completed before the exhaust valve opens towards the end of the power stroke, so ported vacuum drives high temps out the exhaust port and super heats the head, making engines more prone to overheating.
Manifold vacuum is the key. It has to be in addition to initial timing though. So 12-16° initial is with the vacuum line disconnected and temporarily plugged. When you hook up the line to manifold vacuum the timing should advance an additional 10-15° and that’s good. The extra timing at light loads aides in completing combustion during the power stroke. It also allows you to run less throttle plate opening and a leaner idle mixture which improves exhaust smell associated with carburetors. You can also typically drop 2 jet sizes because cruise operation becomes more efficient as well.
So with manifold vacuum there are a couple minor adjustments to be made that generate an overall improvement in engine operation and temperature, but it’s extremely worthwhile.
Initial timing should be 12-16°
Total timing without vacuum 32-36°
Available vacuum advance using manifold vacuum should be 10-15° (adjustable vacuum advance units are about $35).
Please feel free to reach out for additional info. Also, check out my distributor curve video for more information.
Thanks. Liked and Subscribed
Such good info and thanks for spending the time to explain the finer details. That little plastic sleeve may be missing on mine. At only 5 degrees initial timing, my total advance it almost 50 degrees. I will be pulling it apart shortly to see what the problem is. Thanks again!!
Make sure you have the vacuum advance disconnected when checking total advance, but I have seen numbers that high on emissions era distributors that came with vacuum advance/retard canisters. They didn’t really understand how to make the distributor function well back in the late 1960s through the mid 1980s.
@@TheGT350Garage Ok, I thought I had to add up initial timing, mechanical timing and vacuum together to get the total? I was looking for the video followup of the actual set up you talked about. do you have a link to that? I don't see it on your page.
I haven’t had a car available to do the follow up on. I am doing another video on how to get the correct timing curve for a particular engine, that’s coming soon, It’s been a while since I’ve been able to get out and film.
@@TheGT350Garage So if the initial timing and mechanical timing is to add to lets say 34 degrees total, where does the vacuum come in as a total? I saw one other video today that gave an initial of 12 and a mechanical of 34, but the total with vacuum was 40? this confused me, it just didn't add up.
Vacuum advance is never added to total, because total is only really a consideration at wide open throttle. Vacuum advance only contributes to the timing at idle and part throttle when properly connected to a manifold vacuum source. It will contribute to total timing if it is incorrectly connected to ported vacuum, so be sure you have the correct vacuum connection. Ideally. vacuum advance should be capable of adding 12-14° to the timing at light loads and idle. Total timing requirements will be 30-36 degrees depending upon compression ratio, your specific cylinder heads because combustion chambers change the timing requirements, and your cam specs. Every engine is different, so don’t fixate on a specific value, let the engine tell you what it wants.
,,,,great presentation of facts.........Question : Where can I order that plastic limiter , or stop , if my unit has a broken or missing one......Maybe I'd have to fab something to take its place.........anyway ,,,,thanks for the time and knowledge.......
The original style plastic clips are impossible to find. I’ve had good success with black 1/4” poly tubing. It fits pretty snug. If you want a little more you can add a layer or three of heat shrink tubing to take out an additional degree or two.
good video thanks . i have been doing a lot in gm hei distributor. vacuum, weight. springs. weld. Which can be quite nerve-wracking when you've tested a lot. Takes a lot of time. But I won't complain in the future now that I've seen how to do it in a Ford. One problem i have is that when the car runs best(my best adjustment) when it is warm. then the car ran very badly until the temperature rose. So I've had to make a copromise setting. have thought about testing again with the best setting. but have a valve to the vacuum hose that is closed when the engine is cold. then open it when it's warm (maybe work?). I guess the heat affects the gasoline.
If the issue is temperature related it is likely more related to the air fuel ratio than the ignition timing. You may want to try enriching the idle circuit a quarter turn per side and give it a go. Now, every engine is different, and other than it being GM I can’t assume me anything specific about your combination but compression, cam specs, and combustion chamber design all play a role in the start up and idle characteristics. For example a 9:1 454 with an open chamber head with a small dome piston and a moderate cam will behave completely different from a closed chamber head with a flat top or a dish and the same compression and cam. Then, larger or smaller cams change the cylinder pressure substantially. All of that changes the air fuel mixture and timing requirements for start up. I’ve also done a substantial number of GM and Mopar distributors, so if you care to give a little more info, I’d be happy to share my thoughts.
@@TheGT350Garage 350cui. 8,5:1 car van. mayby 230hp.carb 450cfm. duration(50)204&214.hedders. Car runs pretty good now. But if I adjust it so it runs really well when warm. Then it runs very badly for about 10 minutes. If you accelerate normally when cold. then the engine knocks. If I then lose my temper and go full throttle. then it goes well.I know that an engine can knock when it's cold. I don't remember all the adjustments I made but I have it saved but can't find it anymore. I have blocked the heat channel in the head.performer intake aluminum with plastic adapter.I have tested about 10 different vacuum canisters, some of which I have midified (the whole process was interesting). the error comes if I have even lighter springs and increase the stroke on vacuum canisters. and car runs really well when hot. As I see it, it's heat and the ignition?So I've been thinking about this for a while.
That’s a fairly basic and common combination. A 350 with an “RV” or “Performer” style camshaft, 8.5:1, with a small carb in a fairly heavy application. It’s going to have good torque from 1000 to 4500rpm and be all done at 5500rpm (even if it revs a bit past that). That’s not a ton of compression, and if the cam is installed +4 advanced which is typically what that style cam get installed at, you should have about 165-180psi cranking compression. Additionally, you need to keep in mind that a van isn’t considered a light vehicle even if it’s not as heavy as a truck or SUV because of the aerodynamic loads.
Initial timing should be set to 10-12° with your vacuum advance connected to MANIFOLD vacuum. The vacuum advance should be adding another 8-12° so the engine idles with 18-24° cold or hot. Remember manifold vacuum goes away with throttle so as you accelerate the engine runs primarily on mechanical advance. Using ported vacuum for the vacuum source, especially with a small carb that produces instantaneous high vacuum levels in the venturi of the carburetor will rapidly add timing as load increases causing pinging and knocking.
The springs in the mechanical advance should bring your advance curve in gradually from 1000 to 3000 RPM, with mechanical advance “all in” at 3000. I usually recommend 20-24° be the advance limit for most distributors these days and you can fine tune the total timing by changing the initial. If you want 34-36° you’re there at 10-16° initial when you add the two together.
That combination for a 350 won’t rev excessively fast, and the vehicle is relatively heavy, so a fast advance curve will ping and knock at lower rpm and part throttle. If you are using ported vacuum for the vacuum advance that will compound the problem you are experiencing because as you try to accelerate the vacuum advance will add even more timing to your mechanical curve, pushing the engine way too advanced.
Compare the recommendations to your notes, I suspect you’ll see improvements with little effort.
@@TheGT350Garage i have 165psi. and manifoldvacuum. I'll try when I have time and desire.
For the small price of $500 you can buy an HEI that is totally programmable with an iPhone! Rate of centrifugal advance, mechanical advance and vacuum advance. Can be tuned to perfection and also features an anti-theft device that you can set from your phone when you leave the vehicle. Not cheap, but you can spend many many stressful hours tuning and phasing an HEI distributor and sometimes yield very little change welding and shaping those mech advance plates. Ask me how I know? 😂
Dwell is the length of time that the points are closed. Current flows into the primary side of the ignition coil during the dwell time, building up a magnetic field which collapses when the points open. The collapsing magnetic field induces energy into the secondary side of the coil which creates the spark. Dual points allow a longer dwell and thus a higher energy spark. The dwell time is still influenced by engine speed though as the higher the speed the shorter the dwell time and the weaker the spark. Electronic points systems, whether magnetic or optical, trigger a pulse of energy into the coil of the same length regardless of engine speed so the spark energy remains constant. With a constant spark energy you can open up the plug gap a bit wider to make a bigger spark for more reliable ignition.
Dwell is very much a function of point gap on the point cam. Less point gap produces more dwell. Dual points cheat the dwell time by holding the trailing breaker point closed while the leading breaker point is open, then quickly closing the leading breaker point after the trailing unit opens. It was a mechanical solution to an electrical problem. Electronic ignition systems still suffer from the loss of dwell time as RPM increases, this is why we use individual coils on modern cars, the saturation time is substantially higher and so is the energy behind the spark.
Your final comment about opening up the point gap sounds as though you mean the spark plug gap. After 30+ years of playing around with plug gaps, I’m not a fan of increasing the plug gap significantly. My long term observation has been that wide plug gaps shorten the life of the spark plug wires by loading their resistance electrically. As cylinder pressure rises, so does the resistance in the plug gap, add to that The gap between the distributor rotor and the terminals in the cap, and the resistance in the plug wires, there is a significant loss in spark energy at the spark kernel. The coil wire bears the heaviest burden of the electrical load, then the spark plug wires. I’ve had .055-.060” gaps take out a set of MSD Super Conductor plug wires in less than 15,000 miles, so the largest gaps I run are .045” on naturally aspirated engines using about 9:1 compression or less. With boost or high compression that gap must be reduced, so at 12:1 I run .032”-.035” gaps. On a supercharged 9:1 engine running 15psi that gap will be .025-.028”.
@@TheGT350Garage I did mean plug gap (and have edited my post) but I don't see how a wide plug gap can damage the plug wires. For the load in the wires to increase, the resistance across the gap would have to decrease.
@@TheGT350Garage you are right about how the dual points work, the points are wired in parallel and the period in which each one is closed overlaps. I'm not sure about electronic ignition systems suffering a 'loss of dwell' at higher RPM. What's happening is the sensor triggers a monostable multivibrator - a circuit which produces a pulse of a defined width. This pulse width is small compared to the time between sparks so one pulse should not effect the next. What may be happening, in a capacitive discharge system is that as the time between sparks decreases then the capacitor may not have time to fully charge. This would lead to a decrease in the energy in each spark at higher RPM.
You would think that, but with high voltage, if the spark can’t jump the gap in the cylinder it wants to go somewhere, that’s going to be down the boot along the porcelain, or through the weakest point in the insulation on the conductor.
@@TheGT350Garage OK, that's plausible. In any case the gap increase I'm advocating is small. 0.6-0.8mm which is 23-30 thousandths of an inch. It improved the idle quality in my '69 Ford Custom with 302.
One more tip. I think it was standard ignition that sold vacuum chambers you could put an 1/8 th inch allen in the tubing hole and turn a stop to limit the amount of advance you would get at full vacuum. They probably got cheap and dont do it anymore. I`m a 75 year old timer and got that damn dementia on top of CRS ( cant remember shit) so ask the parts guy to pull one out and take an allan with ya and just feel if you can grab hex inside of the chamber reaching through the hose fitting and fishing for the allan fitting.
So, the stop doesn’t always limit the amount of advance, on some vacuum advance units (most actually) it changes the spring tension and changes when the advance applies, this is better than limiting the total advance because it can be adjusted to make sure the advance is not applying below 4-6” of vacuum, and that’s how we can ensure the advance doesn’t stack under load and cause issues.
Hi Walter, I have a question in regards to the duraspark distributor install on 289 engine with a carburetor setup ,,,
Do you have to use some type of ignition box for this distributor to
function ? I like the benefits of this distributor over points ignition but I'd prefer a factory look in the engine bay without an external ignition box .
Good quality videos,
Cheers
You can use an original style Ford Duraspark ignition box so it looks like a factory upgrade. If you really want to do it up, grab one from a junkyard, gut it and put a GM HEI module in it, wired through the old blue plug, or you could even just “hide” the HEI module out of sight and keep the wiring super clean and simple along the factory routing.
I’m running a Pertronix Digital HP ignition, it’s very compact (about the size of a Duraspark II module) and can be mounted discreetly. Example locations would be below the hood hinge on the fender apron, under the dash, or anywhere that suits your needs.
Very informative video. You mentioned primary versus secondary advance springs. Also, there are two different numbered advance slots. To determine the total centrifugal advance, do you add both numbers together? Thanks. I'm having pinging in my 69 gt350, and I think I have too much centrifugal advance.
So, on your 351W with stock compression you need to curve the distributor using a 10L advance limiter (20°) and use 10-12° of initial timing (vacuum hose off the advance unit). Then you need an adjustable vacuum advance mechanism connected to manifold vacuum. If you don’t have a 10L send me an email and I can provide detailed instructions to modify your current (or a similar spare) distributor to be completely compatible with the needs of your engine on pump gas.
@@TheGT350Garage Thanks. I verified what I currently have with a timing light today. With vacuum advance plugged, I have 10 initial and 30 total, which is exactly what you recommended. When I connect the vacuum advance, my initial timing jumps up to 18. I removed all the washers from my OEM ford vacuum advance to allow maximum advance as per the ford shop manual. It made no difference after I removed the 1 washer in the advance housing. I will look into purchasing an adjustable vac. advance for my C9OF-T autolite distributor. Is there a part number/brand you recommend? I have a Holley Sniper EFI on my Shelby, and I noticed my coolant temperatures seem to have dropped by 10 degrees after connecting my vacuum advance according to my hand held monitor screen on the Sniper, which is a good thing! Also, could you post the part numbers of conversion parts to make my cap and rotor into a durapark set up? Thanks a million for the help in your videos. Very informative.
The black Duraspark conversion parts (only ones that look good on a relatively vintage engine in my opinion) are:
Standard Motor Production FD156T Adapter
MSD Street Fire 5505 Cap & Rotor (w/Brass)
You can use spark plug wire sets for a 1985 Mustang GT 5.0L-4bbl (Manual Transmission). But I would recommend a custom (cut-to-fit) set, personally I like the MSD 8mm Street Fire wires for “basic” combinations or the MSD 8.5mm Super Conductor wires with aftermarket ignition boxes. Use either straight boots or 135° OE Ford Duraspark type boots for best results.
If you want an adjustable vacuum advance you can use the following Standard Motor Products part numbers for Autolite or Motorcraft distributors:
VC-31 single points (inc. Pertronix) Adv. ONLY
VC-192 single points (inc. Pertronix) Adv./Ret.
VC-221 Duraspark Advance ONLY
There is currently not an advance/retard available for Duraspark distributors.
A multi spark box still enhance this modification won't it?
I’ve got a freshly rebuilt 289 that is bone stock except for slightly improved (truck/RV cam). My stock ford distributor has no mechanical advance because the weights and springs are corroded I’m suspecting. Thanks to your video I’m ready to dig in and take it apart. What total timing and about what RPM should I shoot for it to come in at? It’s set at 12 degrees initial and idles well but has very little power due to no advance. Thanks!
Total tends to be about 3-4° less than the original factory spec because off the changes in the fuel. So you’ll find yourself in the low 30s. The curve should bring the timing in fully about 500rpm above your typical cruising rpm. Vacuum advance should be in place to layer in an additional 10-14° at idle and cruise speeds.
@@TheGT350Garage great thank you!
@@TheGT350Garage I got the breaker plate pulled off and
I have to really give the rotor a good pull to twist it some but it doesn’t snap back into place like it should would the springs holding pressure. I’m assuming my springs are a little too worn out. I’m attaching a picture of what I found. Is there anything that looks out of wack? I’m thinking something needs to be lubed but I wasn’t sure the correct lubricant and where to put it because it feels kinda sticky.
Gday Walter,
Do you have a part number of the vac adv canister for the duraspark dizzi ?
So the canister adjustment is changing spring tension which allows tuning of the vacuum hg where you want vacuum advance to disappear ?
Any advice on using alum terminal vs brass terminal dizzi cap (Duraspark ) with HEI module or multi spark ignitions ?
Cheers
Use a Standard Motor Products VC-221
,,,,another question ,,,,,concerning the duraspark unit ,,there are three wires to the terminal plug....the ground is easy to find , about the other two that go to the coil ,,what color is the positive lead and what color is the negative going to the ign coil......
Black is ground.
Orange is Mag+
Violet is Mag-
It’s a magnetic trigger so it generates voltage in a sine wave (A/C Voltage). The ignition box interprets that signal and uses it to fire the coil. Because it’s A/C voltage and a sine wave, Mag+ and Mag- are relative to leading edge and trailing edge of the reluctor wheel. If you swap them it alters the signal but it still runs. Some older capacitive discharge ignitions don’t like them swapped.
I have a fully stock 1970 429 except for the intake manifold and carburetor. Those are a factory ford spreadbore intake and an edelbrock 1905 carb.
On today’s pump gas, what would be good numbers for the timing , mechanical advance and vacuum advance?
I have it installed in a 76 f150 4x4 with a 4 speed and 35” tires.
Thanks
I had a similar setup in a ‘77 F-150 years ago. At 10.3:1 compression a 429 needs more lift and duration than a stock cam provides. The stock 360hp Thunder-Jet cam builds a lot of cylinder pressure and as a result the engine can be hard to get the timing right on. I would suggest limiting mechanical advance to 18° and running 10° initial. This will give you 28° total mechanical timing. The timing needs to be about 80% in at cruise rpm, so if you have 4.11 gears with a 35” tire and drive 65mph, about 2600rpm, and all in by 2900-3000.
The vacuum advance needs to be on manifold vacuum and should give 10-14° additional timing above 6in/hg. Below 6in/hg you want vacuum advance to pretty much go away.
Set up like that it should run reasonably well on 91-93 octane pump fuel, but you also need to make sure the air/fuel ratio is in the right range. That engine needs to be a bit richer due to the iron heads, so targeting 0.85 Lambda or about 12.0-12.2:1 at WOT, about 13.5-13.8:1 at cruise and 14.1-14.3:1 at idle should get you right where you want to be.
you can fit Duraspark cap on points dizzy for accesses to better quality/more common wires. you can all so use a 1980 international distributor cap it has hei terminals but small points cap size. the vacuum advance info for fords is lacking on can specs. ford points dizzies are my favorite as you can change the springs and change the amount of advance with out the trigger star getting in the way. all so just 2 vacuum advance part numbers for the non smog one port vacuum cans on 1971 down Dizzy's from standard motor products vc 25 vc31. wells has one that covers 1957-71. use points to trigger tfi module. moto craft or blue streak points. do look in to the 1980 international scout cap! all so try the tfi module on points vary hot spark with a tfi coil. the points last forever when used as a trigger. can use msd box as well. the tfi module + heat sink looks like the optional Motorola ignition from ford from the 1960s that was points trigged. hate the e clip for the vacuum advance i use a Jesus clip looks the clip on ford oil pump shaft just have to get one that is small. it works with points plate. I have ran as low as 20-22 total on a 1979 351w tried 32* and was no better played with octane no better. ran 2* base +20 or 10l slot with a lot of vacuum advance on manifold. got 20 mpg and good power out of a 1979 351. the springs made all the difference. in the 1960s up to 1974 we used ron like Europe. Amico unleaded premium in 1967 had a 97.5 ron to get the modern ron+mon/2 you subtract - 4 to 6 to get to modern pump number. 93.5-91.5! right where we are to day. leaded was 100-103 ron. you are one of a few left that understands this old school tuning! the old ford shop Manuel got me to understanding them! have heard old timers use vacuum hose on the stop pin as well as bending the stop pin. this is gold thanks \/
The reason for the larger diameter of the Duraspark cap is to prevent internal cross-firing in the cap. The small post type caps are susceptible to misfire just the same as a points/socket style cap.
The reluctor on a Duraspark is fairly easy to remove, as I showed in the video. Points will still wear and require maintenance even as a low current trigger. The Ford TFI modules were not known for their reliability, even heat dinked and remote mounted. It’s hard to beat the GM HEI modules for reliability and they are compact and simple to use. Using an aftermarket ignition with features like a rev limiter that meet your needs is best.
There are less vacuum advance inits available these days, but there are more than two or three. Thankfully a variety of Fords were adjustable from the factory.
Your ‘79 351W doesn’t like timing because it has massive 69cc combustion chambers and dished pistons that resulted in nearly no quench area. The pistons are well below the deck, and as a result the perfect storm of bad combustion chamber principles is working against you.
@@TheGT350Garage thanks for the info! do you know the vacuum advance canisters part # that adjust the TOTEL AMOUNT OF ADVANCE not the rate of advance? for points stuff i have used the standard vc31. how about dura spark part numbers? like that trick to get the relocator off. and yes to the big cap for better rotor phasing. was just bringing up the international distributor cap as it is a why to have the 'STOCK' look not as a improvement other than better terminals. i like the points as it gives one a back up if the module craps out. do you know ware to get a duel point barker plate the one for the vacuum advance duel point 428 from 1969-1970? all so can one use a bit of small hose on the limit pin to shorten the advance curve? the old dizzy had a thin wall bit of rubber hose instead of plastic clip. been told you can use thick wall vacuum hose to shorten the curve. as for total timing I have heard all sorts of numbers. looking at the 1969 shop Manuel that lists dizzy specs and base timing it seems that 25-34* total was common. this 36+* must be for Chevy or dodge. never seen people run as low as i did but I found that 20-22* total worked best with it all in at 3500-3700 on my 1979 351w. ran good got good mileage never ran hot. people go too advanced.
Good chance you have the wrong timing pointer to balancer alignment unless you’ve properly verified TDC with a piston stop.
The ‘69 351Ws I’ve taken apart all had 13L (26°) advance limiters. With 6° initial that’s 32° total, about right for the 10.7:1 351W-4V on premium fuel. Those engines today set up best with 28-30° total all in at 3000, with vacuum advance set up for 10-14° at full manifold vacuum.
There are no dual point plates that allow vacuum advance, and if you’re triggering any kind of module dual points are useless, and the ford Duraspark magnetic trigger is the best trigger in the industry -as in used by MSD and other companies for triggering purposes with tremendous reliability.
I just saw a video saying you can get a male plug cap for an older style international in the smaller style
Possibly, I don’t keep up on International parts. The larger diameter is also beneficial by having more distance between the terminals and preventing the possibility of cross arcing.
@@TheGT350Garage makes sense, it’s basically the dizzy they’ve used since the early 60s with just a space player and a bigger cap and rotor?
How many RPM is a duraspark distributor good for? What box is best to plug it in to for higher RPM? I would like something good for 8,000..... I have a hipo plus two other 289’s that I drag raced in the early 80’s one ran 12.80’s and one ran 11.80’s in a ‘62 Ranchero. Keep in mind this was pre 5.0 days with not much sbf aftermarket...😂. Neither engine would rev past 7,200 RPM and I ran an old ford duel point distributor. I want to tinker with them again, but want to run better valve springs and distributor and rev higher.
The magnetic trigger on a Duraspark is the same as MSD uses. In fact, MSD used to build Duraspark distributors for Ford Motorsport SVO in the ‘80s and ‘90s, using blueprinted stock housings, shafts and centrifugal advance mechanisms. They locked out the vacuum advance on the trigger plates and that was a typical distributor in NASCAR for quite a while. 8000rpm is completely in the capability of these distributors with a little preparation, and without resorting to bushing the housing or installing bearings. Check out my recent video on assembling ported 351W heads for some valve spring insight.
1959 352FE with pertronix ignitor III, stock hyd cam with autolite 2100. 9:1. It seems like I can't ever give it enough timing. Have it at 16 initial, and total is only 28. Vacuum adds 14. Idles at 18" vac.
What do you mean by “can’t give it enough timing”? Is it pinging at more than 28° total or does it want more than 28° total and you need more (like 34-38° total)?
Idle vacuum is good, that indicates a sound engine, and the vacuum advance is working as intended there.
What does your curve look like? Timing at 500rpm increments from 1000rpm to 4000rpm? If you lift the point plate what marking is on the distributor advance? 10L? 13L? 15L? The marking is distributor degrees so you double that number for crankshaft degrees. What springs are installed? Light? Heavy? One of each? Two of the same? A single spring total?
The 352 as do other FEs have a D-shaped wedge shaped chamber and terrible quench because the piston is down in the hole 0.055” and a 4.33” diameter head gasket that is typically .042-.048” thick crushed. The end result is that the low compression versions of the engines can be prone to pre ignition or they can demand demand far more timing than expected, depending on the camshaft and the cranking cylinder pressure you’re seeing. FE engines have to be treated on a case by case basis.
@TheGT350Garage I'll get you those numbers at 500 RPM increments. If seems like it needs more timing due to some surging between 1000 and 1600 RPM (it is a manual) during gentle acceleration. If I give it more initial timing that goes away, but it ends up being 20 degrees initial.
I've never heard it ping, we have E10 87 octane here in Maine at 1000 feet elevation.
Thank you so much for your reply!!!!!
You may need more fuel. E10 behaves “lean” with stock jetting. The stoichiometric ratio of E10 is 14.08:1 vs the gasoline your carburetor was designed for which was 14.7:1. It’s usually corrected with an increase of two jet sizes. If that is an original 2100 Autolite carburetor, from 1959, the jets are interchangeable with a Holley. If it has been replaced with a later carb, you’ll need the larger Motorcraft jets.
Are 15L and 10L always together, or can it be 10 and 13 etc sometimes. I have a plate that is corroded, I can't read the #'s.
The plates are always a 5° spread. So 10L/15L, 11L/16L, 12L/17L etc. I’ve seen them up to 18L/23L, that’s a crap ton too much advance. We really need a supplier of close tolerance replacements, and then we’d have something awesome to work with. It would be nice to have someone produce weights too.
Man thanks ☺️ 👍 I wish I seen this video before I bought a Pertronix 3 .
I never new what that felt was for I always thought it was to protect the screw underneath 🤣.
I'm about to pull my Pertronix out and put my motorcraft back in , so I'm assuming you adjusted your vacuum advance using a vacuum gauge ? Giving it around 7 hg ? .
I have a 390 Fe in my 69 F250 it has a Comp 265/275 cam and I put a 4bbl with a RpM intake I have a adjustable vacuum advance motorcraft dist with Pertronix 3 module and coil . I can only get 91 here in so Cal I'm wondering how close the Ford Mr gasket recurve kit springs are to the GM points advance springs I bought that kit since I was using the Pertronix 3 dist.
That's some info there I didn't know I could get a adapter for a dura spark and cap /rotor and make a HEI style set up either muchas Gracias .
So, the GM springs can be used but they fit a little funky because they are longer. You just have to make sure they aren’t loose. FE engines, especially 390s do tend to need a little more timing than other Ford V8s. You’ll probably want to be around 33-35° total mechanical advance and get the vacuum advance to give you everything it has by 4-6” of manifold vacuum.
If you have the means to fully disassemble the distributor, you can clean the housing with a small bore brush, clean and polish the distributor shaft, and use a dry film lubricant (commonly used for firearms and easily found online) in the housing and on the polished shaft. Then a drop or two of engine oil in the bottom of the housing and it should feel amazing and spin with absolutely no resistance.
@@TheGT350Garage I ended up getting the Ford ones the GM ones fit pretty good although not sure if they were stronger or weaker than the Fords . Also I had the 10L and 15L distributor so I just left it at 10 L to make 20 + my 10-12 initial will be 32 total if I go past 12 degrees initial it starts funny like a run on start it's better at 10 _12 for good starts .
My distributor only has the 10 mark on both sides . If I take that lil plastic bushing out will it give me 5 degrees more for 30 degrees mechanical advance ? .. also with the dura spark can you run that to your coil with the hot wire from the dist or does it have to be ran through the module ? And is the D.S.distributor cap fit the HEI plug wires or is it exclusive to the dura spark.
@TheThirdWheel618 so, if you have a 10L leave it a 10L (20°). It’s better to make up total advance with more initial timing than to run a bigger advance curve. For your FE you’ll want 13-15° of Initial timing plus the 20° advance curve to get 33-35° total. Vacuum advance helps with idle quality, engine temperature, and fuel efficiency. As I mentioned before, it should add timing above 6in/hg of vacuum.
Duraspark has a magnetic trigger that operates a module, so yes a module is mandatory. I like the Pertronix Digital HP these days. Nice unit for the money.
The Duraspark cap is a post style just like an HEI, so the HEI style wires from your Pertronix will work.
@@TheGT350Garage thanks 👍 my engine acts funny if I go past 11 degrees initial maybe it's just me thinking it I can only get 91 octane here . I seen the cap and adapter pretty much everywhere lowest year said 77 I'm hoping that will fit .
Hi, I just checked my timing on my 69 Ford Ranchero 351W with a stock distributor. Set the initial timing is at 10 deg. but when I reved it up to 3000 rpm to check the total timing, it is not advancing at all. It stays at 10 deg. all the time. I have a stock distributor with a Pertronix electronic conversion. Vacuum advance was also disconnected & plugged before hand. Any ideas or tips what I should do next? Bad Distributor? Or maybe take it apart to check mechanical advance?
Pull the point plate and check the advance mechanism, sounds like it’s stuck from corrosion or gummed up. Lubricate it in the center hole under the rotor, remove and replace the felt as necessary. Use a good penetrating oil and let it soak in to free things up. Don’t neglect the weight pivots either.
Hi, Thanks for the info. I got the clip out of the cam weight base assm, but the base is frozen and will not come off the shaft. I sprayed some penetrating oil in there to let it soak, hopefully it will come off soon. I tried lightly prying up on it some but its froze good. This car sit for several years outside before it ran again, so I think it got some moisture in there. Do you have any addtional tips for getting it off?
@alicenfred a small 2-jaw puller would be helpful. Alternatively, simply putting an adjustable wrench or channel lock pliers into the housing and working the advance plate to free it after the penetrating oil has had time to work should free it up. Email me if you need specific suggestions on pullers.
Hi, I got the advance plate off, Thanks. Is the knurled shaft removable? Underneath it is a bunch of dirt and rust that should be cleaned up. Now Im thinking maybe I should obtain a new or rebuilt distributor. The knurled shaft has back & forth movement also that I am not sure should do that? It moves about 1/4". Thanks
@alicenfred the knurled shaft is part of the main shaft and is not serviceable. If you have more than .005-.010” side to side clearance, the housing and/or shaft is exhibiting enough wear that replacement is needed.
one question to remove the weights the plastic retaining clips will break. what do you use to replace the clips or can you get new ones and where. thanks
There isn’t really a need to remove the weights unless the distributor is in really bad shape. If that’s the case, a replacement would be a good idea because at home most enthusiasts don’t have the tools to check the bushings in the housing and the shaft for wear.
@@TheGT350Garage you mentioned to remove them to make them lighter plus i have had the plastic clips break from getting brittle from heat but have no idea what to use to replace them are there clips available from somewhere thanks
@@roytouet1203 I was scrolling through here to ask the same thing I got a pair of distributors with cracked weight retention clips. I can't find anyone with a source to buy them.
So it looks like I need to get an ID, OD, and height measurement to see if spacers can be bought. Then hope I can find an E-clip that will work to hold them down.
@earlbrown the plastic bushing and clip is a non-serviceable design and was only ever available as part of a new or remanufactured distributor. What you can do if your clips are damaged is use a distributor shaft from a points distributor, the pivot shafts were larger and the weights pivot on the pin directly, allowing a simple E-clip to hold the weights on.
If you intend on running your engine above 5000 RPM, you don't want to use the Duraspark ignition box, it has a 5000 RPM rev limit built into it. Ask me how I know.
I’m running a Pertronix Digital HP, they’re slick, and work with the original current triggered tachometers used in my Shelby and other Ford products of the era.
Awesome @@TheGT350Garage
If my base timing is 12 what is my total timing my engine is 289 with 302 heads standard cam
Should be 32-34° but you’ll need to use a timing light to figure it out.
Hello can you help me I have a detonation problem on my 351 stroke to a 408 strip street Windsor that I just can't get rid off.
Initially I started with a 10.5 to 1 compression, but the braking pressure was 350 psi on all 8.
So I decided to use dish Pistons to lower the compression to 9.5.1 in retarded the cam, I still wind it up with 220 PSI of cranking pressure. I swapped cams and was able to get it at 195 psi.
And it still detonates like crazy. I have tried recurving the distributor. Obviously play with the timing initial and total different carburetors. Nothing seems to work. Any suggestions??
Sounds like your calculations for static compression were way off or you went way too small with cam selection both times. 10.5:1 is not a problem, but cam needs to be mid 230s duration @.050” minimum for street use.
What is the piston to deck clearance on your engine? And are you using a ‘69-71 block with a shorter 9.480 deck height and not factoring that in by chance? What cam are you currently using? How is it installed? What heads?
You may have an issue with quench area. Too much space between the piston and the head, incompatible shapes between the head and the piston causing poor flame travel.
There are solutions but they may require changes, but to offer you any more complete guidance I need to know a lot more about the combination.
@@TheGT350Garage heads are afr 1420's cam is solid Howards 230° duration and Block is a "D" 80's Block, i dont recall the piston deck clearence but it for sure just alittle in the hole.
Hector, the cam is actually pretty small for a 408, that’s basically just a hair bigger than a 289 HiPo cam. You’re snapping those valves open and shut on a set of high flow heads and getting a pretty stout cylinder fill, that’s why the cylinder pressure is so high.
Then you have the issue of quench area. A stock 351W has the piston .035” down from a 9.480 deck and .058” down on a 9.503 deck, add the thickness of your head gasket (typically .041”) to that and you’ve got .099” quench. The dished piston makes it worse because the flame travel is moving in different directions and not smoothly across a flat piston crown. You’ve got a difficult setup to work with.
I’d go back to a flat top and use a Cometic gasket with a .027” compressed thickness to get rid of as much quench as possible without a complete rethink of the combination. Then I’d put more cam in there, something in the 238-242@.050 intake and 244-248@.050 exhaust range, ground on a 112 LSA and installed on a 112-114 ICL, and with .560-.600” lift. It’s a huge leap and sounds like it’s not streetable, but it won’t have the issues you’re having now even at closer to 11:1 compression. Total timing will need to be in the 27-29° range, and you’ll need to tune for .85-.88 Lambda (air/fuel ratio). With that it will run great, drive great, and be relatively trouble free.
How do you like duraspark 3?
Like is not a term I associate with Duraspark III. It was used in conjunction with EEC-III and is completely unusable for a performance application. Those systems are not serviceable by anyone who has not been trained and without the proper diagnostic equipment. EEC-III was an era when Ford like the rest of the industry were trying to computerize carburetors, those were wild times and dark days for this industry. My advice has long been avoid Duraspark III.
MSD Distributor Advance Recurve Kit # MSD8464
For MSD and GM distributors that kid is absolutely fine but for a Ford distributor the springs are not the correct length to maintain a proper curve in the long term and Ford specific springs should be used.
One year only. OEM Steel gear pre EEC IV control…
Yes, that is a hard to come by original Ford distributor for an ‘85 Mustang GT 5-speed car. Not a common part. Ford Motorsport SVO then Ford Racing sold a kit with this distributor including cap and wires from about 1997-2002. It wasn’t super popular despite being very affordable and considering the number of crate engines that were produced and sold in the era.
@@TheGT350Garage People think they need a $400 MSD I suppose. The beauty of the Duraspark as you stated is how short it is. Particularly on BBF’s. Ridiculous how tall aftermarket dizzy’s are. Appreciate the info!
@ProjectFairmont the lack of vacuum advance on so many of the aftermarket distributors is really more problematic, particularly with a street application. When you have varying operating conditions you need varying amounts of timing and taking the time to understand what your engine wants is more work than some seem to be willing to undertake. A drag race application with mechanical advance is fine, it’s closer to steady state operation, street cars are far from steady state, open track and autocross also requires more adaptability. It’s just hard for people to wrap their heads around.
@@TheGT350Garage I see what you mean. I need every bit of initial advance moving my Lincoln MKV behemoth that is provided by the vacuum advance Duraspark dizzy. And with your help, I now know how to control total advance.