Z06 Whisperer

Was just wondering what you all like to see your air/fuel ratios at (non track tune)?

I recently saw the most beautifully flat graph line ever (well it was compressed on the graph and took the person 5 dyno runs to get it, but still ) and would like mine to look that way.

Thanks!

0Randy@DRM

We like to see about 12.9-13.1, on NA street cars..

Randy

davidfarmer

I agree, 13.0ish. OEM is usually a bit richer (my 97 was 12.5), so I fattened it up 3%

I ran my old WC Vette right at 14.7, not by my choosing, but that's the way the PCM GM sent me did it. I think they programmed it for 58psi fuel pressure, but of course, forgot to tell me. That being said, I never hurt an engine due to it, and won my Mosport race running that lean. In my old videos, you can see the dash-mounted wide-band I used to run.

FactoryRaceCar

Z06 Whisperer

Thanks for the feedback! My exhaust tips have a bit of black "soot" and I'm not sure whether it's possibly due to my car running rich or just left over from when my (non stock) cats were clogged last fall.

What would you all recommend as a track air/fuel ratio? Would you consider that ratio to be a more or less agressive one?

Thank you!

wtknght1

Tuning an engine is a real art. There are programs out there (like LS1 edit), where you can adjust the ratios, timing, etc. to get the car's max power. However, what you have to watch for is detonation - when the mixture, etc just gets too lean. Most of the track tunes I've seen are around 13.0 or so. When we've tuned my engines, the leaner they can run it (without detonation), the more power it will have. Some run rich...some run lean. No two are ever the same. Most well tuned engines though will get within 10 HP of each other and seldom is that the deciding factor on who wins or loses a race.

In other words, don't get too wrapped up in tuning and HP numbers - races aren't decided on the dyno. Put a good, reliable tune on there and drive the wheels off it!