NikwoaC's "Commitment Issues" Engine Build

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Well fellas, I was so anxious about this whole mess, I about fell over after the first run was made. Turns out, I don't have to light it on fire.

The below graph is from run #3 of 4 total. First pull, right after driving the car there, it did 333 and some change. Second pull we added timing (from 14 base to 16), and it went 334.X, but went as lean as 14.0X around 6200. Third pull I added 5% fuel, and it did 336, as seen below. AFR on that pull was around 13.6high. So I added another 4% and we did a 4th pull with hardly any cooldown time and it came back down to 333ish, but AFR was at a more comfortable 13.low.

I'd like to point out that it made over 300 HP starting at about 4900 (where I have the data line set to, below) and just carried out until the dyno operator cut it off at about 63-6400 RPM on every pull.

So I'm beginning to think the car weighs more than I think it does, judging by my dragstrip trap speed, LOL. Time to go on a diet. (And learn how to drive.)

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That is phenominal, bro! Just about the best looking street 302 I've seen. Your theory paid off, and hopefully paves the way for future combos.

I'm :leghump:in' stoked! You built a monster. Makes me happy I went 205cc on my 331 instead of chickening out on 185s. I'm sorry I ever wasted time on AFR165s on my old 302. Just keep datalogging on the street and at the track. You might find that the AFR changes a bit while the car is actually moving and under real load. Chances are you've made a noticeable improvement.

I hereby renounce my incorrect estimation and revert back to the one I made when I knew more about foxes ;) :
Did your cam guy tell you where he'd expect the motor to peak? I know your cam specs are buried somewhere in this thread, but IIRC it was 215/224 with a 112LSA right?

With a 224/228 111LSA cam on my 302, the motor peaked at around 5300rpm. That was with a small set of heads and a cobra intake, though. With a somewhat similarly sized 228/224 (114LSA I think) on my 331 it actually peaked about 1000 rpm higher, which I attribute to the big flowing AFR205s and Box upper TFS-R intake.

The following is entirely made up of loose-logic based on my old builds... chalk it up as speculation and nothing more:
Your cams intake duration is considerably smaller than either of those cams, so that should bring the powerband down a little. But your heads and intake should breath similarly to the ones on my 331, which will bring it back up. The smaller displacement would shift the powerband up in rpm (or down in power at the same rpm), too. My guess is your engine's theoretical peak will be somewhere north of 6000 rpm. Maybe 6500-6600 RPM? I've never tried to estimate a power peak on a motor before, but that's my best guess. If that's right, then I think you're going to make 335-355rwhp (SAE, dynojet) at 6000 RPM. Is that how high you want to run it on the dyno?
 
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That is phenominal, bro! Just about the best looking street 302 I've seen. Your theory paid off, and hopefully paves the way for future combos.

I'm ****in' stoked! You built a monster. Makes me happy I went 205cc on my 331 instead of chickening out on 185s. I'm sorry I ever wasted time on AFR165s on my old 302. Just keep datalogging on the street and at the track. You might find that the AFR changes a bit while the car is actually moving and under real load. Chances are you've made a noticeable improvement.

I hereby renounce my incorrect estimation and revert back to the one I made when I knew more about foxes ;) :

Thanks man! That's funny that you had predicted so close before... Were you starting to lose faith? :)
 
Thanks man! That's funny that you had predicted so close before... Were you starting to lose faith? :)
Um... I guess so. I think the new guess was based solely off of your trap speed, but I expect that'll be coming up pretty nicely. I would be interested to know what the car weighs. Seems like you ought to be going 113-115 mph through the traps. I think those 3.73s should be fine to get you out of the hole and giving you room for more in the future.
 
time for real gears (4.10-4.56) and traction. I think it could trap 114-115mph with a few simple things.

Man, you crazy. I'm perfectly happy with my 3.73s. It already makes too much noise at highway speeds haha.

I have been toying with the idea of putting the car on a bit of a diet by ditching the 28 lb Mach 1 wheels for some Billet Specialties Street Lites (still 17s to clear the brakes), maybe a tubular K-member and A-arms, and then maybe some long tube headers and 3" exhaust all the way back. That would put the 351 build on hold for another year, but it would be kind of fun to see how fast I can get this 302 to go. Plus, with a new exhaust setup, a switch to 1.7 rocker arms, and maybe a box upper intake, I think I could crack 350 @ the tire, which would be pretty awesome.
 
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