Finally went to the dyno!

Coltrane

Greasemonkey
Jul 6, 2020
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Hey everyone - after a few setbacks with the new motor (I'll be making a full thread with everything that's been done up until this point, stay tuned) I finally made it over to the dyno shop!

I made a thread awhile back for people to place their guesses for the hp/tq, and you can check that here: https://gbodyforum.com/threads/hp-tq-guesses-just-for-fun.88051/ (the thread is closed so I can't add this new info to it)

I went in hoping to make at least 350hp to the wheels, and it made 374! (with 367 tq) One thing I'm really happy about is just how flat the torque curve is. I know I'm leaving peak hp on the table only using a dual plane intake (rpm air-gap) but it's 90% a street car so I wanted to keep it (we'll see about in the future though).

With sticky 28" drag radials, 4.10 gears, a 3200-ish converter (I think I'm going to need to go around 3800 or so, but we'll see later this year) I'm hoping to click off some 11.9s! (tracks should open in March, so I have some months to go...)

IMG_1041 2.JPG
 
I wouldn't put stock in the numbers as fact, but it does look like your converter is working the way you think it is and it looks like it pulls clean to 6000 so I would try shifting it about 6200 and see how it goes.
 
Let's see who was closest! Here were the guesses:

DROLDS84 - 476/502
Streetbu - 395 at the tire
bracketchev1221 - 425-430
scoti - 440ish at the crank
NJ Longroof - 457 at the crank
olds307 and 403 - 479hp and 456tq at the crank
SoFloG - 410 at the tire

The actual numbers are 374hp and 367tq at the wheels, so assuming 20%ish drivetrain loss that's around 467hp and 458tq to the crank. Looks like DROLDS84 is closest on hp and olds307 and 403 is closest on tq!

Just a reminder of the setup:
SBC 355 (hydraulic roller), roughly 9.7-1 compression w/ forged rotating assembly
AFR Eliminator 195 heads
Custom comp cam .602/.608 lift, 235/243 duration, 110 lsa
Holley 750 double pumper
Edelbrock rpm air gap intake
200-4r with 3200 stall
4.10 gears
28" tire
 
I wouldn't put stock in the numbers as fact, but it does look like your converter is working the way you think it is and it looks like it pulls clean to 6000 so I would try shifting it about 6200 and see how it goes.

It should have been run out higher on the Dyno. I'd argue shift point would end up being 6500+. Only way to know for sure is to run it up higher and pick a point where it operates in the highest average HP based on RPM drop on the upshifts. Looks like it shut down right at peak. Who knows? May have peaked a smidge higher if it was run out more.
 
It should have been run out higher on the Dyno. I'd argue shift point would end up being 6500+. Only way to know for sure is to run it up higher and pick a point where it operates in the highest average HP based on RPM drop on the upshifts. Looks like it shut down right at peak. Who knows? May have peaked a smidge higher if it was run out more.
We did a couple other pulls where we went up to 6500ish, but I just didn't post them here because they made slightly less power. It makes peak right at 6k and slowly drops off - we think it's 100% due to the intake, which is fine with me. I'll most likely be shifting at 6300-6400. The bigger issue is the converter, only flashing to 3200. I think I'll leave it alone until I'm actually on the track in the spring so I can see exactly what it's doing. I'll set up a camera mount pointed at the tach to review the footage after as well.
 
With all that, you don't think it'll be faster than 11.9s?
 
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