Air fuel ratio talk.

[nightspeed87]

I couldn't agree more. It's all about VE and getting optimal flow for the setup. I know that my stock intake manifold and lack of a front mount holds the motor back from making even more power and that it'll be a whole new ballgame when those parts go on.

Especially since your a 2g. Smaller intake manifold and tb.
Yea and I agree also my thing is, I want to squeeze the most power out of my engine as
I can before raising the boost. Of course adding boost is the easier thing to do, but you will be missing a lot. I try to look for power in places ppl dont think about, ( grounding kits,port and matching, compression, etc. ) Wish I had the money to have stroked the new engine going in but o well.

Anyways thanks everyone for the a/f information. I will make sure my chip is made for 11.1 air fuel ratio since this seems to be the consensus for the optimal/ safe pump gas ratio while still being able to play with timing .

 

[scottsee]

Correcting for an 11:1 at 16 degrees made a massive difference and it ran 12.95 at 105.20. Leaning out more did nothing and I tried maps at 11.5 and 11.7:12 with the same timing and only minimal changes in trap speed. A sizeable came from taking the timing to 23 degrees on the 11.5:1 map. That netted me my 12.57 at 107.85 and the power delivery was markedly different.

That makes sence. I was at the track, tuned 12:1 AFR and ran 12.7 @ 110. Second run was 11.8:1 AFR, 12.5 @110. Third and final was 11.5:1 AFR, 12.42 @ 111. I didn't bother moving the timing maps, I'll give that a try..

 

[andymoraitis]

That makes sence. I was at the track, tuned 12:1 AFR and ran 12.7 @ 110. Second run was 11.8:1 AFR, 12.5 @110. Third and final was 11.5:1 AFR, 12.42 @ 111. I didn't bother moving the timing maps, I'll give that a try..

Accounting for minor differences in launch and shifting, your results pretty much tell you that once A/F is in a sweet spot, making changes to it won't likely do much. I bet you'll have some fun messing with the timing though. Keep us posted as to your results.

 

[RipperXX]

So basicly it looks like everyone is saying, 11:1 - 11.5:1 Air fuel ratio, with as much timeing as possible (without getting stupid) and remove as many restrictions to the intake/exhaust will get you the most power.

 

[Kevin Jewer]

That's the jist of it.

For any given rpm and load timing will increase power up to some point of diminishing return, then it will reduce power. The point where the curve flattens out is where I like to be. I'm considering buying a couple hours time on a load bearing dyno so I can do this tuning on the EVO's AEM.