These are the dyno tuning results of Scott Cook's (Re-Raise) G8 before the APS Twin Turbo Kit. This was done with 100% stock car including exhaust and air box. A/F is an ultra conservative 12.0. While we had a peak numbers gain of 21 hp. There is close to a 30 hp gain in different parts of the curve.

Dyno Jet 248
SAE Correction Factor
Smoothing set to 3

Run 001 Stock ECM 291.6 RWHP 316.1 RWTQ
Run 012 Tuned PCM 312.6 RWHP 336.1 RWTQ

http://24.26.129.28:50001/Dyno%20Graphs%20and%20Pictures./Dyno%20Graphs/Scott%20Cook%20G8%20Forum.jpg

What grade fuel? And same for before and after?

The before dyno was done with 87 octane. We switched to 93 and it made virtually no difference. Leaning out the air/fuel was where the power increases came from, rather than the octane.

So what if you lean it out to a 13:1 AFR and run 93 octane?

If memory serves me right, that's what the LS1 F-Body guys go for (13:1 AFR)

The before dyno was done with 87 octane. We switched to 93 and it made virtually no difference. Leaning out the air/fuel was where the power increases came from, rather than the octane.

No added timing? Just leaning out? What was the stock A/F?

So what if you lean it out to a 13:1 AFR and run 93 octane?
That’d be ideal, but the car seemed knock happy, and we prefer to keep our tunes on the safe/conservative side. We’re guessing that the factory exhaust system is a big restriction on this car. After all, it has two catalytic converters, then a muffler, then two resonators, and then two more mufflers!


No added timing?
Correct. We kept the ignition timing stock for the above before and after results.


Just leaning out?
Yes, leaning, with lots of smoothing work too. See the bottom blue line in the above dyno chart. Notice how it’s textbook-like flat? That’s the beauty of what Brian does. :)


What was the stock A/F?
Just take a look at the bottom red line above. You’ll see that it starts at 12.0:1, but ends up at nearly 10.0:1!

Thanks for the info. I'm doing the cat-back first, then the intake/tune.

Is Brian using HPTuners Suite? I'm pretty sure that's what you guys at Intense used with the 3800 crowd. (I had a few Intense parts on my car at one time) :)

Thanks for the info. I'm doing the cat-back first, then the intake/tune.
That sounds like a good game plan to me. :)


Is Brian using HPTuners Suite? I'm pretty sure that's what you guys at Intense used with the 3800 crowd. (I had a few Intense parts on my car at one time)
Yes, INTENSE was actually HP Tuners' very first customer several years ago. :D We still use HP Tuners for all our late model GM dyno tunes, and we use that in combination with GM's EASE/SPS for all our mail order PCM's.