I keep telling those knucklehead buddies of mine to watch the stuff before they build engines but they never listen I guess their loss is my game thanks for your show it really helps
This shined light on a question I've had kicking around in my head for quite a while the 1.94 / 1.6 combo. Made sense to me as you keep the velocity higher on the intake side and let the exhaust flow better.
This has been exactly my experience on small cubic inch engines.... Go to a1.60 exhaust valve, good headers and healthy stick. Great drivable torque in a big cube hydraulic roller.
You may try a 1.62 on exhaust and up to a 2" maybe on the intake. Or a 1.95" and 1.625. etc. there used to be many valve sizes available hope still are.
Yes the only time a biggest valve possible is more appealing when the cam comes right off at the seat and that big punch of air popping in really fast, until it slows down, unless the head can still make energy to keep pulling it, the smaller valve wins out to being unshrouded easily after that initial break open.
Youve confirmed what i had heard , leave the inlet side , the exhaust is where the gains can be had . At least you have do e the hard research on them not just hearsay . Much appreciated . Carnt wait for the next installment . Thanks for your efforts . Take care . Cheers Adam from Oz 👍👍
leaving the 1.940" intake valve, and adding the 1.600" exhaust valve might just be enough difference to alter what type of cam pattern you want. With the stock heads I know a dual or split pattern cam is ideal. With just that upgrade though, might be enough of a change to make a single pattern cam work well. What makes me happy about that is the fact there are a lot more single pattern options out there.
Thats 100% correct, you dont have to "crutch" the weak exhaust with a dual pattern cam but often times a dual pattern will still make slightly more power
Just found your channel, very impressed with your work piss cutter! Finally someone is posting do's and don't s of porting vortec heads backed up with flow numbers. Keep up the good work, thanks!
Nice to see you had very noticeable gains on the 1.60exh valve upgrade.... i experimented doing the same going with SS 1.60 valves on the exh, but kept the 1.94 valves for the int, i had a reputable machine shop rework a set of stock 882 smog heads(76cc) along with some pocket porting, modified for 3/8" screw in studs and guide plates back in the mid 90s for a 4bolt 355cid sbc street engine for my 2dr 1975 chevelle back in 1993, 4100#s with me in it. Other parts included a stock crank, stock rods, ARP fasteners throughout, hyperutectic flat top 4valve relief pistons, figure a good 9:1cr at least, eldelbrock rpm dual plane intake, holley 3310-1 750vacsec carb, 1 5/8" headman headers, full 2.5" exhaust with 40series flowmaster mufflers, GM 4:10 gear with posi out the rear, a TCI 2000rpm 12" stall converter, a stock TH350 with shift kit, comp cams 270(224@50/.470 int and exh lift/110ls) single pattern flat tappet camshaft, comp cams 1.5 roller tip rockers and aftermarket hardened pushrods. For the money i put into those heads, many will say i could have gone aftermarket, which is true, but this was my very first engine build, and i like to experiment, this combination of parts netted me consistant 14.40s in the 1/4 mile doing about about 93mph at the strip and did not too shabby as a street cruiser too. I was in my mid 20s then, probably didnt know any better, but i did some research and had some help figuring out what would work and what wouldnt, but i was totally satisfied with the out come and it was reliable as it was strong, not a single issue the whole time i owned the car. I also experimented with a set of sbc aluminum trickflow heads(2.02-1.60/64cc) afterwards(they wer ok), but then i finally settled on a set of SR torquer iron heads(2.02-1.60/67cc) and they were great as is for me. Sadly, i sold the car off back in 2009 after 16yrs of ownership, but now i've got a very clean 1979 malibu 2dr coupe with a ZZ4 crate engine along with a 700r4, and i couldnt be happier to be in the hotrod game once again except for these darn part shortages now(argh). So in short, going with 1.60exh valves seemed to have helped even when i had no way of knowing for sure, with a flowbench or other wise, but it was just my logical way of thinking, "keep the 1.94int to help keep the torque where i needed it(down below) because of the heavy car, and go 1.60exh to help it breath better over all.
Some food for thought for anyone interested. I've got a set of Pro Topline 906 "Vortec" replacement heads that originally came with a 1.94 intake and 1.5 exhaust valve. These are relatively old heads, but it does show that some Vortec style heads can improve with a larger valve. To go with the new valves, I blended the throat cut into the pocket and just barely touched the short side with an 80 grit roll to smooth a ridge they all seemed to have. I left the intakes as the carbide cut them, no smoothing. I did smooth the exhaust slightly with a 80 grit roll (essentially just removed the carbide divots). The low lift on the intake is improved dramatically, while it's much less improved at higher lift. Intake w/1.94" Valve Intake w/2.02" Valve Difference 0.1 54 72.5 34.26% 0.15 104.7 0.2 103.9 136.9 31.76% 0.25 167.2 0.3 146.6 192.3 31.17% 0.35 215.5 0.4 194.4 231.6 19.14% 0.45 238.7 0.5 224.3 237.7 5.97% 0.55 239.6 0.6 226.2 239.6 5.92% Exhaust w/1.5" Valve Exhaust w/1.6" Valve Difference 0.1 49.3 45.3 -8.11% 0.15 82.7 0.2 87.6 108 23.29% 0.25 128 0.3 118.8 148 24.58% 0.35 170.7 0.4 139.7 176 25.98% 0.45 178.7 0.5 148.5 180.7 21.68% 0.55 180.7 0.6 152 181.4 19.34% You can see I actually lost flow at .1 lift on the exhaust, but it is greatly improved at all higher lifts. Unfortunately, I'm not sure what depression or bore size these were taken on and my machinist isn't around to ask anymore. Perhaps one day I'll get my Third Gen TA into driver status and get it onto the chassis dyno to see what kind of numbers it can put down. It does feel and sound pretty healthy though with a XR276-10HR.
Another great video Pat, I really appreciate all the info and help you have passed my way, and if anyone is needing a spring kit for the vortecs, well, he has a awesome kit . Just got it running last night and for what it is, I came alive....
are pressed in you going to have to use screw in studs and Guide plates at that lift? Like I said this is your show I'm looking forward to the next episode.
Yes on the intake side When you switch to the 202 You have to notch the side of the cylinder wall and the head Chamber Just so it would flow properly Yeah you nailed it On the valve shrouding
Just found yer channel. Good stuff. I'm a low buck guy, outa necessity. Very interested in Vortec heads, and you've taught me a helluva lot in the last hour! Subscribed! 👍
I always thought a 1.55 exhaust valve let you clean up the stock seats on 062 heads and get rid of the stepped valve seat that comes on the hd truck heads. I have never heard of guys needing to swap intake valves because they are the pinch. A 2.00 1.6 valve package might be the ticket and let you really put a proper multi angle valve seat in them.
Been watching a few of your Vortec vids and this one is 👍👍 Exhaust gains I can see proof of across the whole curve. This will get me closer to the exhaust #s catching up with the intake #s. That majic 75% flow # 👍 I'm trying to do my homework and this is a gr8 help 😊 1.94 - 1.60 with just a tad of bowl work 👍
I watched your video. I have a set of big valves 906 I haven't ran but watching your video ancers my ?.And I have been running stock intake and bigger exhaust for the past 7 years and they perform well. I did lot of research on the vortec and everything I read talked about the exhaust beings the hold up . Then you came out with your findings and just proved it. Good info.
I would like to see back to back dyno runs with stock 906 vs 2.02/1.6 906 heads. Heard from a very reliable source that it may not gain on the flow bench but absolutely gains on the dyno.
Yes it would be a great youtube video but heres why is would be hard to do. A vortec head with a 1.94 or max a 2.00 intake valve needs some porting to optimize but no a whole alot to really get the power most guys are looking for with a small runner head. Ive found that a 2.02 can show gains but needs alot more porting to optimize that valve. The biggest issue being the thin castings on vortecs. I will actually not make a video on how I got vortecs to flow 260+ cfm with a 2.02 valve becuase most guys will wreck their heads trying to port them that much. The larger the bore the better the 2.02 can be with a vortec, but again from what ive done its minimal because of the small runner size and valve shrouding. Some other guys may have some different results than me but for most street/strip builds the 1.94 works great for power and longevity
@@cuttersperformance they guy I’m talking about was doing a dirt car and rules did not allow porting. So he just cut the seats to the lager valve and ran a bowl hog down the remove the step and that was it, was like 20+ on the dyno if I remember correctly.
Love your videos. Building this 2nd gen camaro. Planning engine with an extra strong 4 speed. Appear all bone stock with 454 c.i. stroker small block chevy all under stock hood. No power brakes. No power steering. Although with AC.
I be love your information I’m trying to build vortex head 350 for my camaro just getting back on Feet From battling colon cancer I don’t have lotta money so this board tech information is amazing my goal is 350 to 400 horse hoping I can achieve that
Man sorry to hear about the cancer! Hopefully all is well now 🙏 I'm glad to hear your liking my channel and if you have any questions feel free to email me a pcperformance1@outlook.com 350+ hp is quite easily done with vortec heads
Thanks for the dedication and hard work you've put into getting this information out there. I do have a question you may be able to shine some light on. I've went and pulled a couple sets of vortecs from the junk yard and given them a good porting. I decided to try a set of 1.6" exhaust valves, using a set of neway cutters I scored for cheap on ebay. My question is: did any blending have to be done after upsizing the valve seat? It seems like there was no way to cut up to 1.6" without taking out some of the "shroud" above the valve. A picture is worth a thousand words! Thanks
Yes actually ive been meaning to do a video showing this. If you dont open up the throat to 90 to 92% of the valve size, then the larger valve will actually hurt flow
Another great video! Pretty typical results for a small chev head. Exhaust mods always makes for better gains. That 1.6 valve also had a nice smooth transition. The 1.5 would see better results if it was back cut. Look forward to the next one. Wondering, what part of Canada are you in?
@@cuttersperformance oh shoot an Ontario brother! i was thinking of pulling some junkyard vortec heads to put on my 5.7 TBI that's gonna go into my safari van and you've been my main source of info! if i do go through with pulling them I'd genuinely come and bring them to your shop to be worked over mister pisscutter!
Excellent information. We race a dirt track stock car. Most everybody is going to the LS, but I am going to try to stick with the small block. So very interested in the exhaust flow. What I am seeing here, is that I do not need to keep looking for those dark 180 heads. Very, very exciting! The cams we run by rule state that they have to pull a high vacuum number. Therefore, we are not allowed to run much more than a simple “RV“ camshaft. Doing some things with some custom grind and some lifters. But, really considering switching from the camel hump over to the vortec. A little bit of constructive criticism: instead of the gray background, can you switch that to a white background? It’s very tough to see some of the different colored lines. for my old eyes, it is especially hard to see the blue and the gray
Great job great job dude I always wondered about more cam lift on exh & 1.6 valve? Chevrolet is synonymous for low-flow on the exhaust side keep up the good work looking forward to your next video🤙
You may get better and more consistent flow bench numbers if you have a radius entry to smooth the flow into the intake port. Otherwise the sheer edge creates turbulence. You can use clay like a lot of people do. I made radius entries from hardwood using router bits on a mill. I use a small amount of clay to blend from whichever one is closest to the port I'm working on. Also, I found the 2.00"/1.55" combo works well on these heads.
We have used radius inlets, clay on the intake and pipes or on the exhaust. Changes seem to depend on the head. 2.00 and a 1.55 or 1.6 seem to be the best combo for vortecs. Mind you the 1.94 valve seems to be just fine for most applications Cheers!
for my first Late Model Vortec headed engine, I only did 1.6 exhaust and stock 1.94 , NO porting , that was not legal. 525HP on the dyno. 12:1 34deg total timing, Super Victor, 830 Holley
Just with a little bit of porting and polishing vortex heads do great, if you polished those combustion chambers and exhaust ports to a shinny mirror finish would be a big improvement in keeping carbon build up down and efficiency up . .
If you lay a older SCB head gasket over your vortec head you can see a bump in the gasket where the FACTORY RELIEF CUT reaches out on the 461/291 Fuelie casting 2.02 valve.
I'm actually kind of interested to see what would happen if you put 1.60 exhaust on those older 350 heads that have like 1.72 intakes. maybe not interested enough to try but I will search for a video on it, lol. either way this sounds like a good idea, and thanks for taking the time to actually flow test them.
Go bigger on the exhaust side with a 1.65 and just slightly bigger 2.005 on the intake side should produce some interesting flow bench numbers unlike the more traditional 2.02 1.60 combo. Let's see you do that test and see what the flow bench numbers are
I have had the idea of a mild boost vortec build, using 1.94"/1.60" with only bowl blend and port polish, maybe under cut and swirl polished valves, polishes chambers, with about 10psi boost, for a street engine, I believe the most gains are in Port matching and polishing! With a street engine, and the right cam!! The biggest thing is the correct cam for the job!
@@cuttersperformance by polish I don't mean a true polish, I only remove casting lines, and usually leave a 220 grit or so finish, so by polish I basically mean not enlarging the port, but always Port match, about 2" into the port on both sides,
Guy walks into his local machine shop..... Guy: Yes sir...id like to get just my exhaust valves enlarged in these heads please! Shop Guy...Just the exhaust...are you crazy...why? Guy...I saw it on PISS-CUTTER...Just Do it...trust me!
Nice show brother you got another subscriber for sure keep them coming .I would love to see a show on Chevy interchangeability because GM for along time had lots of interchangeability between their cars , trucks and vans something that has been lost in this race to make as many throw away vehicles as possible .
this was great ! have you done any test with 8.1 heads i think it would be very interesting to see the same test with the 8.1 heads not a lot out there on that engine
Questions: Have you tested valves on Vortecs with a necked-down stem for more flow? Have ya ever used 8mm valvestems? I just wonder if they make any meaningful difference in an otherwise stock Vortec, considering the mild valve lifts and rpm range of these heads.
I read somewhere does vortec heads didn't like the 202 that they really favored the 194 but going up to the 202 just didn't help him at all but going to the 16 help them tremendously on the floor bench I even saw TH-cam video wish somebody actually did this it made have been you but anyway that's my two cents I hope it helps. But the video you did on the 305 Vortec heads and put a 194 add to 16 in them that they would flow just as good as a 350 because you got them just as close as you did to the 350s I believe that it would not do the 350s myself because of the smaller combustion Chambers I've always liked the 305 inch because of the smaller Chambers and most of the time they have as big of Runners as the 350s anyway when you get to 4K subscribers I sure would like to be in the giveaway I love your channel and all the trial and error that you do with Vortec I think it's cool and I learned a lot from you
My 1996 Silverado k1500 after a several thousand dollar rebuild came to me as a non-runner. One of the significant improvements he made was a set 906 heads mildly ported with bigger valves and I have to say it runs really well
Have you come across 906 heads with valves that look like they have been about 80 or 90% backcut? I just finished tearing apart the driver side head and cleaned them up with a brass wire wheel. Has the normal wear mark of the seat contact but also has a similar width band or ring where the normal ridge would be closer inwards toward the stem. Kind of like a 2 angle valve job on the valve not the seat. I have pics...
Great video dude I was doing this 20 years ago Flo benches just came out so it was relatively expensive if you don't mind doing a little bit of research Hot Rod Magazine I'm fairly sure was one of them dad an article which gave you everything and it was how to get 400 horsepower out of a stock 350 on a budget they tell you the cam which was the Xtreme Energy buy comp cams ? The intake 2 years the size of carburetor and I built one it was a Beast for you know $1,800 that includes the short block and everything so it's worth your time to research it I'm sure the magazine she can access it online but just go back about 15 16 + years and I'm almost positive that's the title budget Vortec
Hey brother, love your work! I have a question. There is a guy in my area selling vortec heads that he has ground down the stems and put 202 intake and stock 1.5 exhaust. He is running stock springs. Is this combo sketchy?? 202 with 1.5?? How would the flow be with 202 and 1.5 valves??
In one of David Vizzards vids, he talks about welding in a tiny spot on the intake side of chamber to increase flow. He used clay and it took flow numbers up way past 700 lift. Have you tried doing that????
I have played with puddy on the flow bench with no real results. I dont think theres enough meat in the top of the runner to really get the benefit of raising the runner and epoxy the floor. I know there are guys out there with high modified vortecs with welded roofs that may benefit.
Hello friend, I was wondering if u ever tried the 1.6 ex and left the 1.9 in ??? Im working on a set of vortex heads right now, and my machinist said on a hot street motor it would not do any good to go to 2.2 and 1.6 valves. But I c ur test is proving something here, so i just might get him to put me 1.6 n the ex and leave the 1.9 n the intake side.. please let me know if u did try this, and if it worked out like ur #'s showed n this test... very interesting 👌 I like ur videos, u explain alot more them most.. A+ 🤙
@@cuttersperformance 1.6 exhaust valve. Currently looking for something with a undercut and swirl polish. Dropped 5 906 castings off and only 2 checked out ok. I’ll probably try contacting you about valve spring recommendations. Looking forward to more videos, your killing it so far with real numbers and not just bench racing. 🤘
Awesome man! You'll have a great set of heads Especially with a abit of porting (videos soon) And yeah email me at pcperformance1@outlook.com for valve springs
Try on the exhaust seat angles 30 45 then as close to straight down as possible on the last angle going down into the port. Almost a 2 angle valve job. Added power to my dirt car but never verified it on a flow bench. Way out in western NC
Suggestion, when you get a head everything done to it that has been tested out good, do a stock versus you best improvement head dyno runs! $$ I know, but if you could that would be an excellent vido!
I don't know if anybody's posted this already but GM did the research on this and found out that the best flowing head was the 2.00 as in the GM fast burn heads anyway this is what I believe
I'd like to see pressurized flow numbers I'm running my Vortec heads with boost only 8 psi but I put 2.02/1.60 valves in mine and took all the casting flash off the intake and exhaust ports.
I imagine a larger 2.02 valve would work better for a larger maxed out cylinder bore size? Maybe bored to .060 that way the head chamber can be unshrouded a little better, going past the stock bore size scribe marking to the .060???? I know its tiny, but it does allow a little bit more unshrouding on intake side. I'm thinking larger valve would work better with larger cylinder bore which allows more unshrouding. A larger valve on stoke bore size makes shrouding worse. What are your thoughts?
Its more the runner than the issue rather than the shrouding of the chamber. To really benefit from the 2.02 valve you need to remove enough meat that you risk grinding through on a thin vortec casting. 2.00 intake/ 1.6 ex is a nice combo for vortecs
I've been wondering what the truth was on porting and valve size increase on vortec heads. With the increase in percentage of flow could make a big difference in power i suppose. What were the actual flow numbers of the exhaust? The gains you show from Increasing the exhaust valve size makes me curious about how it could benefit the peanut port heads on a big block chevy. Do you ever think about doing some big block stuff?
There will be more data in my next video! cheers! but heres the 1.6 exhaust flow with stock port .100. 62 .20 123 .300 151 .400 171 .50 177 .600 180 .700 185
Looking at the newer videos you’ve been doing, I wonder if the 305 vortecs without the heart shaped chamber so more room in the head would produce more flow with a 2.02 valve? I know it defeats the purpose of keeping it on a 305, but I have a set lying around and I’d like to see the difference in bigger valves without the heart shaped chamber?
I have my short block all done 40 over with a 1.25 domed hyper piston I had a set of 441 heads ported and polished ...with 76cc chambers said to have 9.6.1 compression all said and done wouldn't i have been further ahead with a flat top 2 v relief and 906 heads ?
Hey my friend I'm seriously interested in that PC performance kit that you have four more Tech heads Says it'll take a 580 lift Also I mean hey But do you think it's going to make the most power With the must tour cuz I'd really like to build another one but I lost all my information On my last set up Basically cam specs and stuff that you would use Along with the spring kit and everything I hope this makes sense some kind of tired Thanks bro
So glad your getting the feedback you deserve you have much great information and knowledge to give it's highly appreciated. I'm starting a vortec 350 buil very soon and I need all the info I can get. Looking forward to the giveaway!!!!!!!😁
@@cuttersperformance Yeah that was a bit of a surprise, I’ve always heard that the exhaust ports need a little work, but didn’t expect the 1.6 valve to help that much. 😄
@ Pat, snice you already have the 2.02 valve in and have confirmed less than signifigant gain, maybe you could lay that combustion chamber back around the valve on the cylinder side and see if that gives an improvement. i read in David Vizard's book that laying back the chamber was a important step in prepping a head. personally i never understood why they put such a sharp curve on the cylinder side of the chamber. i get that the cylinder is RIGHT there but just, scribe the cylinder and lay back the chamber to the cylinder edge on the out side. i think this would be an improvement whether you're using 1.94 or 2.02 valves. when i took my votecs in to have screw in studs and 1.6 exhaust valves put in, the machinist argued with me over the 2.02 intakes and i firmly insisted NO. he was not happy with me.
Yeah I'm probably going to unshroud the valves on the 2.02 as I did on the 1.94s that I tested and got some gaines (video coming up) Good call going the 1.6 on the exhaust
@@cuttersperformance thanks, i did a ton of research on forums before i made a decision on what to do. the consensus i got was there was no gain and what little their was was of no benefit to what i wanted the motor for, driving my truck on the street. i look forward to the test of the unshrouding of the 2.02
This is new ? We ALWAYS want you use a 1.6 rocker on exhaust, over a 1.5.....So why wouldn't a larger valve exhaust side help ? Doesn't those two items make sence ?? ...helping the exhaust.
Look for the 906s there less prone to cracking. Look on box trucks at the junkyard there usually low mileage and very well took care of. I got 2 sets both sets were good and looked almost new on the inside.
@@brandonbell8159 all junkyard near here don't deal with anything to do with sbc anymore they deal with 2004 and up stuff i have one good 906 head like get anther one i know what to look for it just hard with junkyards not having sbc stuff and if they do they will only sell the hole engine as a core for $500
I missed out on a set of those recently. Asked a question ten mins after they were posted up, and another guy just snapped them up. Oh well, not in a hurry
Yeah David Vizard is a legend and I've seen alot of his videos and own his books. Very smart man and doesn't act like he knows it all even though he probably does haha
How do I email you directly for some advice. I am building a engine for dirt track late model racing with specific rules, using stock crank and stock rods with larger arp's, 062 heads 355 vortec block flat tappet cam, need help with cam and springs with the rules no roller lifters, can have roller rocker arms 1.5 , no porting heads or polishing, can deck .010 only, springs checked on engine with lsm gauge 105lb seat and 260 open and open pressure checked at .450 lift. Will have 3 angle valve job, stock valve size, I can undercut but no hollow stems, also has to have stock valve seals, 11/32 diameter. Can use 650 or 750 on high rise intake either single or dual plane, stud style rockers only no shaft, doesn't matter anyway with crap lift rule, anyway 3/8 mile high banked clay ovals, I need to come off the corners so can't sacrifice all my torque, idle quality doesn't matter no vacuum rule, I was leaning towards a 108 to 110 lsa, not sure about the duration though and has .460 max lift rule to tangle in, so lsa and lift duration and springs suggestion, and 650 or 750 cfm carb? Consider that I can't flow much more than stock with lift rule.
@@cuttersperformance correct me if I'm wrong but I believe the 2 angle seats were only in 3/4 tons and 1 tons along with the bigger 3/8" exhaust valve stems
love it man saves money and gains performance
I keep telling those knucklehead buddies of mine to watch the stuff before they build engines but they never listen I guess their loss is my game thanks for your show it really helps
This shined light on a question I've had kicking around in my head for quite a while the 1.94 / 1.6 combo. Made sense to me as you keep the velocity higher on the intake side and let the exhaust flow better.
This has been exactly my experience on small cubic inch engines.... Go to a1.60 exhaust valve, good headers and healthy stick. Great drivable torque in a big cube hydraulic roller.
You may try a 1.62 on exhaust and up to a 2" maybe on the intake. Or a 1.95" and 1.625. etc. there used to be many valve sizes available hope still are.
Yes the only time a biggest valve possible is more appealing when the cam comes right off at the seat and that big punch of air popping in really fast, until it slows down, unless the head can still make energy to keep pulling it, the smaller valve wins out to being unshrouded easily after that initial break open.
Youve confirmed what i had heard , leave the inlet side , the exhaust is where the gains can be had . At least you have do e the hard research on them not just hearsay . Much appreciated . Carnt wait for the next installment . Thanks for your efforts . Take care . Cheers Adam from Oz 👍👍
leaving the 1.940" intake valve, and adding the 1.600" exhaust valve might just be enough difference to alter what type of cam pattern you want. With the stock heads I know a dual or split pattern cam is ideal. With just that upgrade though, might be enough of a change to make a single pattern cam work well. What makes me happy about that is the fact there are a lot more single pattern options out there.
Thats 100% correct, you dont have to "crutch" the weak exhaust with a dual pattern cam but often times a dual pattern will still make slightly more power
You should experiment with 1.94-1.60 reduced valve stems and 8mm valve stem conversion. That would be interesting as well.
Just found your channel, very impressed with your work piss cutter! Finally someone is posting do's and don't s of porting vortec heads backed up with flow numbers. Keep up the good work, thanks!
Thanks brother!
Nice to see you had very noticeable gains on the 1.60exh valve upgrade.... i experimented doing the same going with SS 1.60 valves on the exh, but kept the 1.94 valves for the int, i had a reputable machine shop rework a set of stock 882 smog heads(76cc) along with some pocket porting, modified for 3/8" screw in studs and guide plates back in the mid 90s for a 4bolt 355cid sbc street engine for my 2dr 1975 chevelle back in 1993, 4100#s with me in it. Other parts included a stock crank, stock rods, ARP fasteners throughout, hyperutectic flat top 4valve relief pistons, figure a good 9:1cr at least, eldelbrock rpm dual plane intake, holley 3310-1 750vacsec carb, 1 5/8" headman headers, full 2.5" exhaust with 40series flowmaster mufflers, GM 4:10 gear with posi out the rear, a TCI 2000rpm 12" stall converter, a stock TH350 with shift kit, comp cams 270(224@50/.470 int and exh lift/110ls) single pattern flat tappet camshaft, comp cams 1.5 roller tip rockers and aftermarket hardened pushrods. For the money i put into those heads, many will say i could have gone aftermarket, which is true, but this was my very first engine build, and i like to experiment, this combination of parts netted me consistant 14.40s in the 1/4 mile doing about about 93mph at the strip and did not too shabby as a street cruiser too. I was in my mid 20s then, probably didnt know any better, but i did some research and had some help figuring out what would work and what wouldnt, but i was totally satisfied with the out come and it was reliable as it was strong, not a single issue the whole time i owned the car. I also experimented with a set of sbc aluminum trickflow heads(2.02-1.60/64cc) afterwards(they wer ok), but then i finally settled on a set of SR torquer iron heads(2.02-1.60/67cc) and they were great as is for me. Sadly, i sold the car off back in 2009 after 16yrs of ownership, but now i've got a very clean 1979 malibu 2dr coupe with a ZZ4 crate engine along with a 700r4, and i couldnt be happier to be in the hotrod game once again except for these darn part shortages now(argh). So in short, going with 1.60exh valves seemed to have helped even when i had no way of knowing for sure, with a flowbench or other wise, but it was just my logical way of thinking, "keep the 1.94int to help keep the torque where i needed it(down below) because of the heavy car, and go 1.60exh to help it breath better over all.
Yes the 1.6 valve works great! I have a video coming up about how much flow you can get with 1.6 ported exhaust ports on vortecs. Great gains!
Some food for thought for anyone interested. I've got a set of Pro Topline 906 "Vortec" replacement heads that originally came with a 1.94 intake and 1.5 exhaust valve. These are relatively old heads, but it does show that some Vortec style heads can improve with a larger valve. To go with the new valves, I blended the throat cut into the pocket and just barely touched the short side with an 80 grit roll to smooth a ridge they all seemed to have. I left the intakes as the carbide cut them, no smoothing. I did smooth the exhaust slightly with a 80 grit roll (essentially just removed the carbide divots). The low lift on the intake is improved dramatically, while it's much less improved at higher lift.
Intake w/1.94" Valve Intake w/2.02" Valve Difference
0.1 54 72.5 34.26%
0.15 104.7
0.2 103.9 136.9 31.76%
0.25 167.2
0.3 146.6 192.3 31.17%
0.35 215.5
0.4 194.4 231.6 19.14%
0.45 238.7
0.5 224.3 237.7 5.97%
0.55 239.6
0.6 226.2 239.6 5.92%
Exhaust w/1.5" Valve Exhaust w/1.6" Valve Difference
0.1 49.3 45.3 -8.11%
0.15 82.7
0.2 87.6 108 23.29%
0.25 128
0.3 118.8 148 24.58%
0.35 170.7
0.4 139.7 176 25.98%
0.45 178.7
0.5 148.5 180.7 21.68%
0.55 180.7
0.6 152 181.4 19.34%
You can see I actually lost flow at .1 lift on the exhaust, but it is greatly improved at all higher lifts.
Unfortunately, I'm not sure what depression or bore size these were taken on and my machinist isn't around to ask anymore. Perhaps one day I'll get my Third Gen TA into driver status and get it onto the chassis dyno to see what kind of numbers it can put down. It does feel and sound pretty healthy though with a XR276-10HR.
Another great video Pat, I really appreciate all the info and help you have passed my way, and if anyone is needing a spring kit for the vortecs, well, he has a awesome kit . Just got it running last night and for what it is, I came alive....
Hell yeah brother! Glad to hear 🏁
I like that you actually use flow numbers, and real ones at that, not what they are supposed to flow, but what they did
Thats exactly what I'm going for! These are the numbers right from the flow bench, not what someone found on a forum haha
Cheers!
Great data, pretty much confirms what I've been told. Thanks. What I'm interested in now is how it would go when modded for more lift.
How much lift you talking?
@@cuttersperformance maybe .550 ??
are pressed in you going to have to use screw in studs and Guide plates at that lift? Like I said this is your show I'm looking forward to the next episode.
Yes on the intake side When you switch to the 202 You have to notch the side of the cylinder wall and the head Chamber Just so it would flow properly Yeah you nailed it On the valve shrouding
You’ve been helpful to me and my 906’s! Thank you.
No problem man! Vortecs rock!
Just found yer channel. Good stuff. I'm a low buck guy, outa necessity. Very interested in Vortec heads, and you've taught me a helluva lot in the last hour! Subscribed! 👍
I always thought a 1.55 exhaust valve let you clean up the stock seats on 062 heads and get rid of the stepped valve seat that comes on the hd truck heads. I have never heard of guys needing to swap intake valves because they are the pinch.
A 2.00 1.6 valve package might be the ticket and let you really put a proper multi angle valve seat in them.
Been watching a few of your Vortec vids and this one is 👍👍
Exhaust gains I can see proof of across the whole curve.
This will get me closer to the exhaust #s catching up with the intake #s. That majic 75% flow # 👍
I'm trying to do my homework and this is a gr8 help 😊
1.94 - 1.60 with just a tad of bowl work 👍
I have seen on one other guy on TH-cam say the samething. Exhaust valve mod is the way to go. Good job.
Congrats on the 12000 Keep pushing up bro
I watched your video. I have a set of big valves 906 I haven't ran but watching your video ancers my ?.And I have been running stock intake and bigger exhaust for the past 7 years and they perform well. I did lot of research on the vortec and everything I read talked about the exhaust beings the hold up . Then you came out with your findings and just proved it. Good info.
I would like to see back to back dyno runs with stock 906 vs 2.02/1.6 906 heads. Heard from a very reliable source that it may not gain on the flow bench but absolutely gains on the dyno.
Yes it would be a great youtube video but heres why is would be hard to do.
A vortec head with a 1.94 or max a 2.00 intake valve needs some porting to optimize but no a whole alot to really get the power most guys are looking for with a small runner head. Ive found that a 2.02 can show gains but needs alot more porting to optimize that valve. The biggest issue being the thin castings on vortecs. I will actually not make a video on how I got vortecs to flow 260+ cfm with a 2.02 valve becuase most guys will wreck their heads trying to port them that much.
The larger the bore the better the 2.02 can be with a vortec, but again from what ive done its minimal because of the small runner size and valve shrouding.
Some other guys may have some different results than me but for most street/strip builds the 1.94 works great for power and longevity
@@cuttersperformance they guy I’m talking about was doing a dirt car and rules did not allow porting. So he just cut the seats to the lager valve and ran a bowl hog down the remove the step and that was it, was like 20+ on the dyno if I remember correctly.
@@sethmiller9442 yeah i could see how some combos can pick up abit. The valve job and bowl hog probably played a big role in those gains
Love your videos. Building this 2nd gen camaro. Planning engine with an extra strong 4 speed. Appear all bone stock with 454 c.i. stroker small block chevy all under stock hood. No power brakes. No power steering. Although with AC.
Very cool man! Thanks for checking out my videos
I be love your information I’m trying to build vortex head 350 for my camaro just getting back on Feet From battling colon cancer I don’t have lotta money so this board tech information is amazing my goal is 350 to 400 horse hoping I can achieve that
Man sorry to hear about the cancer! Hopefully all is well now 🙏
I'm glad to hear your liking my channel and if you have any questions feel free to email me a pcperformance1@outlook.com
350+ hp is quite easily done with vortec heads
I sent an email just learning this stuff LOL Hope you got it one question is can you use valves out of older head
Thanks for the dedication and hard work you've put into getting this information out there. I do have a question you may be able to shine some light on. I've went and pulled a couple sets of vortecs from the junk yard and given them a good porting. I decided to try a set of 1.6" exhaust valves, using a set of neway cutters I scored for cheap on ebay. My question is: did any blending have to be done after upsizing the valve seat? It seems like there was no way to cut up to 1.6" without taking out some of the "shroud" above the valve. A picture is worth a thousand words! Thanks
Yes actually ive been meaning to do a video showing this. If you dont open up the throat to 90 to 92% of the valve size, then the larger valve will actually hurt flow
Subscribed, vortec heads for the WIN!!!
Another great video! Pretty typical results for a small chev head. Exhaust mods always makes for better gains. That 1.6 valve also had a nice smooth transition. The 1.5 would see better results if it was back cut. Look forward to the next one. Wondering, what part of Canada are you in?
Exhauat valve was backcut on both the 1.5 and the 1.6
I'm in Ontario eh! 🇨🇦
@@cuttersperformance Calgary
@@cuttersperformance oh shoot an Ontario brother! i was thinking of pulling some junkyard vortec heads to put on my 5.7 TBI that's gonna go into my safari van and you've been my main source of info! if i do go through with pulling them I'd genuinely come and bring them to your shop to be worked over mister pisscutter!
Excellent information. We race a dirt track stock car. Most everybody is going to the LS, but I am going to try to stick with the small block. So very interested in the exhaust flow. What I am seeing here, is that I do not need to keep looking for those dark 180 heads. Very, very exciting!
The cams we run by rule state that they have to pull a high vacuum number. Therefore, we are not allowed to run much more than a simple “RV“ camshaft. Doing some things with some custom grind and some lifters. But, really considering switching from the camel hump over to the vortec.
A little bit of constructive criticism: instead of the gray background, can you switch that to a white background? It’s very tough to see some of the different colored lines. for my old eyes, it is especially hard to see the blue and the gray
Great job great job dude I always wondered about more cam lift on exh & 1.6 valve? Chevrolet is synonymous for low-flow on the exhaust side keep up the good work looking forward to your next video🤙
Thanks brother! More flow videos coming
Was looking forward to seeing the results thanks
awesome! just want I needed to know for my 1980 corvette engine build!
You may get better and more consistent flow bench numbers if you have a radius entry to smooth the flow into the intake port. Otherwise the sheer edge creates turbulence. You can use clay like a lot of people do. I made radius entries from hardwood using router bits on a mill. I use a small amount of clay to blend from whichever one is closest to the port I'm working on. Also, I found the 2.00"/1.55" combo works well on these heads.
We have used radius inlets, clay on the intake and pipes or on the exhaust. Changes seem to depend on the head.
2.00 and a 1.55 or 1.6 seem to be the best combo for vortecs. Mind you the 1.94 valve seems to be just fine for most applications
Cheers!
This is exactly how I’m having my vortec heads done. Running a voodoo cam at .540 exhaust lift
for my first Late Model Vortec headed engine, I only did 1.6 exhaust and stock 1.94 , NO porting , that was not legal. 525HP on the dyno. 12:1 34deg total timing, Super Victor, 830 Holley
Damn son! That's awesome
If you know or don't mind sharing
Could you send me the cam specs im very curious
Pcperformance1@outlook.com
@@cuttersperformance can you produce these cam specs please? Great video by the way!
Thank you for the top notch information it really helps out when you're trying to build something
Thank you, I appreciate that
Just with a little bit of porting and polishing vortex heads do great, if you polished those combustion chambers and exhaust ports to a shinny mirror finish would be a big improvement in keeping carbon build up down and efficiency up . .
Thank you for another very informative video. My next build will get the 1.60 exhaust valves
If you lay a older SCB head gasket over your vortec head you can see a bump in the gasket where the FACTORY RELIEF CUT reaches out on the 461/291 Fuelie casting 2.02 valve.
I'm actually kind of interested to see what would happen if you put 1.60 exhaust on those older 350 heads that have like 1.72 intakes. maybe not interested enough to try but I will search for a video on it, lol. either way this sounds like a good idea, and thanks for taking the time to actually flow test them.
Go bigger on the exhaust side with a 1.65 and just slightly bigger 2.005 on the intake side should produce some interesting flow bench numbers unlike the more traditional 2.02 1.60 combo. Let's see you do that test and see what the flow bench numbers are
I have had the idea of a mild boost vortec build, using 1.94"/1.60" with only bowl blend and port polish, maybe under cut and swirl polished valves, polishes chambers, with about 10psi boost, for a street engine, I believe the most gains are in Port matching and polishing! With a street engine, and the right cam!! The biggest thing is the correct cam for the job!
Most professional porters say that the port polishing doesn't do anything, i haven't done any testing my self on that though
Maybe I should?
@@cuttersperformance by polish I don't mean a true polish, I only remove casting lines, and usually leave a 220 grit or so finish, so by polish I basically mean not enlarging the port, but always Port match, about 2" into the port on both sides,
Ahh ok exactly 👌
Guy walks into his local machine shop.....
Guy: Yes sir...id like to get just my exhaust valves enlarged in these heads please!
Shop Guy...Just the exhaust...are you crazy...why?
Guy...I saw it on PISS-CUTTER...Just Do it...trust me!
Hahaha love it!
awesome data, thank you! So would 1.6 exhaust + ported exhaust really rock?
Hell yeah! Coming up soon in a video
Nice show brother you got another subscriber for sure keep them coming .I would love to see a show on Chevy interchangeability because GM for along time had lots of interchangeability between their cars , trucks and vans something that has been lost in this race to make as many throw away vehicles as possible .
this was great ! have you done any test with 8.1 heads i think it would be very interesting to see the same test with the 8.1 heads not a lot out there on that engine
No but i would love to get set of heads or a complete engine for testing
Nice to see intelligent work that matters on stuff reg mech, use and need thanks bunk auto n small eng.
Thanks brother!
Maybe I missed it. Did you do a correct valve job on the head to fit the 2.02/1.60 valve combo? Or just put it in the head for flow test?
Yeah the head was cut for a bigger valves and probably bowl blended
Questions: Have you tested valves on Vortecs with a necked-down stem for more flow? Have ya ever used 8mm valvestems? I just wonder if they make any meaningful difference in an otherwise stock Vortec, considering the mild valve lifts and rpm range of these heads.
I've tried necked down stems on stock vortecs, with no noticeable difference in flow. I have not tried 8mm stems
Congratulations on 2500
I read somewhere does vortec heads didn't like the 202 that they really favored the 194 but going up to the 202 just didn't help him at all but going to the 16 help them tremendously on the floor bench I even saw TH-cam video wish somebody actually did this it made have been you but anyway that's my two cents I hope it helps. But the video you did on the 305 Vortec heads and put a 194 add to 16 in them that they would flow just as good as a 350 because you got them just as close as you did to the 350s I believe that it would not do the 350s myself because of the smaller combustion Chambers I've always liked the 305 inch because of the smaller Chambers and most of the time they have as big of Runners as the 350s anyway when you get to 4K subscribers I sure would like to be in the giveaway I love your channel and all the trial and error that you do with Vortec I think it's cool and I learned a lot from you
My 1996 Silverado k1500 after a several thousand dollar rebuild came to me as a non-runner. One of the significant improvements he made was a set 906 heads mildly ported with bigger valves and I have to say it runs really well
Vortecs work great!
Cheers brother!
Have you come across 906 heads with valves that look like they have been about 80 or 90% backcut? I just finished tearing apart the driver side head and cleaned them up with a brass wire wheel. Has the normal wear mark of the seat contact but also has a similar width band or ring where the normal ridge would be closer inwards toward the stem. Kind of like a 2 angle valve job on the valve not the seat. I have pics...
Yeah all the vortec valves are cast with a back cut
Sounds great looking forward to the give away💪
Great video , it's no myth . Leave those vortec heads stock .
Great video dude I was doing this 20 years ago Flo benches just came out so it was relatively expensive if you don't mind doing a little bit of research Hot Rod Magazine I'm fairly sure was one of them dad an article which gave you everything and it was how to get 400 horsepower out of a stock 350 on a budget they tell you the cam which was the Xtreme Energy buy comp cams ? The intake 2 years the size of carburetor and I built one it was a Beast for you know $1,800 that includes the short block and everything so it's worth your time to research it I'm sure the magazine she can access it online but just go back about 15 16 + years and I'm almost positive that's the title budget Vortec
Haha yeah man! The vortec heads work quite well with just abit of work 👌
David Vizard explains the benefits of larger valves & porting, bowl work required
Great test. Thanks
Great info, love your videos !!!
Thanks brother!
Hey brother, love your work! I have a question. There is a guy in my area selling vortec heads that he has ground down the stems and put 202 intake and stock 1.5 exhaust. He is running stock springs. Is this combo sketchy?? 202 with 1.5?? How would the flow be with 202 and 1.5 valves??
What about the v6 vortec heads? I’m planning on a 4.3 build and am curious on the head geometry similarities to the 350 heads.
In one of David Vizzards vids, he talks about welding in a tiny spot on the intake side of chamber to increase flow. He used clay and it took flow numbers up way past 700 lift. Have you tried doing that????
I have played with puddy on the flow bench with no real results. I dont think theres enough meat in the top of the runner to really get the benefit of raising the runner and epoxy the floor. I know there are guys out there with high modified vortecs with welded roofs that may benefit.
David Visards latest small block chey book gives data on Vortecs with the bigger valves, with bowl blend and full (basic) port job.
Hello friend, I was wondering if u ever tried the 1.6 ex and left the 1.9 in ??? Im working on a set of vortex heads right now, and my machinist said on a hot street motor it would not do any good to go to 2.2 and 1.6 valves. But I c ur test is proving something here, so i just might get him to put me 1.6 n the ex and leave the 1.9 n the intake side.. please let me know if u did try this, and if it worked out like ur #'s showed n this test... very interesting 👌 I like ur videos, u explain alot more them most.. A+ 🤙
Just dropped my heads off at the machine shop this morning after watching this video the 1st time when it was released.
Hell yeah brother! Are you going to get 1.6 exhauat valves or stick with the stock valves?
@@cuttersperformance 1.6 exhaust valve. Currently looking for something with a undercut and swirl polish. Dropped 5 906 castings off and only 2 checked out ok. I’ll probably try contacting you about valve spring recommendations.
Looking forward to more videos, your killing it so far with real numbers and not just bench racing. 🤘
Awesome man! You'll have a great set of heads Especially with a abit of porting (videos soon)
And yeah email me at pcperformance1@outlook.com for valve springs
@@cuttersperformance Email sent.
Try on the exhaust seat angles 30 45 then as close to straight down as possible on the last angle going down into the port. Almost a 2 angle valve job. Added power to my dirt car but never verified it on a flow bench. Way out in western NC
Suggestion, when you get a head everything done to it that has been tested out good, do a stock versus you best improvement head dyno runs! $$ I know, but if you could that would be an excellent vido!
I'm planning on doing some dyno stuff in future thats for sure
I don't know if anybody's posted this already but GM did the research on this and found out that the best flowing head was the 2.00 as in the GM fast burn heads anyway this is what I believe
I'd like to see pressurized flow numbers I'm running my Vortec heads with boost only 8 psi but I put 2.02/1.60 valves in mine and took all the casting flash off the intake and exhaust ports.
Your biggest benefit with boost would certainly be that 1.6 exhaust valve. Good call on that 👍
@@cuttersperformance I'm also using a cam with higher lift and a little bit more duration on the exhaust side.
I imagine a larger 2.02 valve would work better for a larger maxed out cylinder bore size? Maybe bored to .060 that way the head chamber can be unshrouded a little better, going past the stock bore size scribe marking to the .060???? I know its tiny, but it does allow a little bit more unshrouding on intake side. I'm thinking larger valve would work better with larger cylinder bore which allows more unshrouding. A larger valve on stoke bore size makes shrouding worse. What are your thoughts?
Its more the runner than the issue rather than the shrouding of the chamber. To really benefit from the 2.02 valve you need to remove enough meat that you risk grinding through on a thin vortec casting.
2.00 intake/ 1.6 ex is a nice combo for vortecs
I've been wondering what the truth was on porting and valve size increase on vortec heads.
With the increase in percentage of flow could make a big difference in power i suppose. What were the actual flow numbers of the exhaust?
The gains you show from Increasing the exhaust valve size makes me curious about how it could benefit the peanut port heads on a big block chevy. Do you ever think about doing some big block stuff?
There will be more data in my next video! cheers!
but heres the 1.6 exhaust flow with stock port
.100. 62
.20 123
.300 151
.400 171
.50 177
.600 180
.700 185
Looking at the newer videos you’ve been doing, I wonder if the 305 vortecs without the heart shaped chamber so more room in the head would produce more flow with a 2.02 valve? I know it defeats the purpose of keeping it on a 305, but I have a set lying around and I’d like to see the difference in bigger valves without the heart shaped chamber?
now when you say bowl blend, is that just smoothing out the radius from the cut?
I have my short block all done 40 over with a 1.25 domed hyper piston I had a set of 441 heads ported and polished ...with 76cc chambers said to have 9.6.1 compression all said and done wouldn't i have been further ahead with a flat top 2 v relief and 906 heads ?
Great info.
Question: were the 1.6 exhaust valves back-cut like the stock 1.5's are?
Yeah both back cut
Appreciate the video great job Dude
Thanks man!
Hey my friend I'm seriously interested in that PC performance kit that you have four more Tech heads Says it'll take a 580 lift Also I mean hey But do you think it's going to make the most power With the must tour cuz I'd really like to build another one but I lost all my information On my last set up Basically cam specs and stuff that you would use Along with the spring kit and everything I hope this makes sense some kind of tired Thanks bro
Yeah man! Send me a email pcperformance1@outlook.com
With your combo
So glad your getting the feedback you deserve you have much great information and knowledge to give it's highly appreciated. I'm starting a vortec 350 buil very soon and I need all the info I can get. Looking forward to the giveaway!!!!!!!😁
Awesome man glad to hear! Feel free to email me with any questions
Pcperformance1@outlook.com
Give away will be a good one!
Will do thank you again love your video's. You have my 👍
The port and chamber were designed around a 1.94” valve, I’m not surprised a 2.02” valve doesn’t improve flow.
But are you surprised on how much of a improvement the 1.6 valve made? I was haha
@@cuttersperformance
Yeah that was a bit of a surprise, I’ve always heard that the exhaust ports need a little work, but didn’t expect the 1.6 valve to help that much. 😄
@ Pat, snice you already have the 2.02 valve in and have confirmed less than signifigant gain, maybe you could lay that combustion chamber back around the valve on the cylinder side and see if that gives an improvement. i read in David Vizard's book that laying back the chamber was a important step in prepping a head. personally i never understood why they put such a sharp curve on the cylinder side of the chamber. i get that the cylinder is RIGHT there but just, scribe the cylinder and lay back the chamber to the cylinder edge on the out side. i think this would be an improvement whether you're using 1.94 or 2.02 valves. when i took my votecs in to have screw in studs and 1.6 exhaust valves put in, the machinist argued with me over the 2.02 intakes and i firmly insisted NO. he was not happy with me.
Yeah I'm probably going to unshroud the valves on the 2.02 as I did on the 1.94s that I tested and got some gaines (video coming up)
Good call going the 1.6 on the exhaust
Yes looking forward to polishing and laying back the chamber with the 2.02 intake valves. I just did my heads. On my 4.3 v6. Good content.
@@cuttersperformance thanks, i did a ton of research on forums before i made a decision on what to do. the consensus i got was there was no gain and what little their was was of no benefit to what i wanted the motor for, driving my truck on the street.
i look forward to the test of the unshrouding of the 2.02
@@chriscatarcio7534 how did it come out?
This is new ?
We ALWAYS want you use a 1.6 rocker on exhaust, over a 1.5.....So why wouldn't a larger valve exhaust side help ?
Doesn't those two items make sence ??
...helping the exhaust.
Yep, pretty interested in them too.
I been trying get my hands on some not cracked vortec heads i got 4 but 3 are cracked im not having much luck getting good heads around me
Look for the 906s there less prone to cracking. Look on box trucks at the junkyard there usually low mileage and very well took care of. I got 2 sets both sets were good and looked almost new on the inside.
@@brandonbell8159 all junkyard near here don't deal with anything to do with sbc anymore they deal with 2004 and up stuff i have one good 906 head like get anther one i know what to look for it just hard with junkyards not having sbc stuff and if they do they will only sell the hole engine as a core for $500
just buy them off summit, i think they have new castings for like 350 each head.
@@frotobaggins7169 i might have too
Larry Maux at speedtalk, creator of pipemax did extensive testing of the 062)906 castings with various valve sizes on the bench and engine dyno
2.00" intake valves, like the Chevy "fast burn" heads have. Good compromise, I would think.
Cool video. TH-cam is asshoe I guess I got unsubscribed!!!! Well I have subscribed again lol!!!
I always use undercut stems to help flow a bit.
I tried undercut stems in this test and actually didn't see much of a difference
I think you hit the 4k subscribers easy.
Is it safe to mix 906 with 062 on one block?
Just ordered new Stainless Steel 194’s and 160’s
What is a good aftermarket vortec head that won’t crack? I’m building a overlander 4x4 and need reliable set of heads for my 5.7 Yukon.
Eq heads are nice, I'm also planning on trying the summit racing vortecs. Porting and flow bench
The GM Fastburn heads have 2" intake valves, how about checking the flow for those? If that's not asking to much of course.
I missed out on a set of those recently. Asked a question ten mins after they were posted up, and another guy just snapped them up. Oh well, not in a hurry
Great video. Look at David Vizard's head porting video on Vortec heads. Looking forward to the giveaway.
Yeah David Vizard is a legend and I've seen alot of his videos and own his books. Very smart man and doesn't act like he knows it all even though he probably does haha
How do I email you directly for some advice. I am building a engine for dirt track late model racing with specific rules, using stock crank and stock rods with larger arp's, 062 heads 355 vortec block flat tappet cam, need help with cam and springs with the rules no roller lifters, can have roller rocker arms 1.5 , no porting heads or polishing, can deck .010 only, springs checked on engine with lsm gauge 105lb seat and 260 open and open pressure checked at .450 lift. Will have 3 angle valve job, stock valve size, I can undercut but no hollow stems, also has to have stock valve seals, 11/32 diameter. Can use 650 or 750 on high rise intake either single or dual plane, stud style rockers only no shaft, doesn't matter anyway with crap lift rule, anyway 3/8 mile high banked clay ovals, I need to come off the corners so can't sacrifice all my torque, idle quality doesn't matter no vacuum rule, I was leaning towards a 108 to 110 lsa, not sure about the duration though and has .460 max lift rule to tangle in, so lsa and lift duration and springs suggestion, and 650 or 750 cfm carb? Consider that I can't flow much more than stock with lift rule.
I LOVE THE VOTEC HEAD I JUST PUT A SET ON A 283 WOW DID IT WAKE UP
Hell yeah brother! They work great 👍
What 1.6 valve you recommend ? Thank you
I'm only concerned with the LH half of the flow graph.
Exactly! Like i said most important part to look at is under .500 lift but everyone loves to see max flow haha
👍
How does 062 compare to 906?
Same heads but the reproduction 906s are cast in Mexico
And some 906s HD heads have 2 angle press in seats on the exhaust
@@cuttersperformance correct me if I'm wrong but I believe the 2 angle seats were only in 3/4 tons and 1 tons along with the bigger 3/8" exhaust valve stems
@@konnerkramer329Same valves, even back cut but the seats are 2 angle. Yeah came on the 2500's
I've always wondered 194 174 comb, on 062 head . Will that even fit
Hello I looking for more power l have 350 hp now I want 400 plus can you suggest a head cam combo
Good stuff! 👍
What if you increased the lift after putting the bigger intake valve?
I have found without major porting theres no real benefit