Just got back from the dyno. I only made 1 pull as I knew the car was running lean and wanted to see how bad it was. I made 323rwhp and 332.97 corrected, but the guy said it was 331rwhp uncorrected. I don't have a scanner to post the graph, but the A/F curve was between 14.5-15/1 pretty much the whole pull. How much do you think I can gain when I send the PCM back to my tuner to correct it? This is on a Dynojet by the way.

Jason

 

You might lose hp. Lean is mean until you go boom is what I've always heard. What you'll be gaining is the fact that your engine won't go boom. Ideally, you want a 12.8 AFR up until your peak torque, then have it lean out to 13.1 to your peak hp and then have it richen back up a tad (12.8-12.9) until redline.

 

Well I'm getting a free retune from madwolf on here (thanks Ion). I sent him my a/f graph so the tune should accurate this time. Once I get the PCM in, I'll go back and get some numbers and to make sure I don't have a weak fuel pump or bad injector anything else that might cause the car to run lean.

Jason

 

Is your car an A4 or an M6?

 

read his sig.

 

yeah, thats awefully lean to be pushing ur engine! u want high 12s low 13s for a ballpark figure, and u are way above that. i wouldnt push it too hard, its more prone to blow up!

as for HP numbers, who knows in your case! a leaner car might get more power, not much if any in ur case, but a re-tune could compensate the loss if there would be any and it would probably net you some better numbers with a decent tune!

i wouldnt push a few extra numbers if u risk harming the motor!

let us know what happens

 

Yeah since the dyno run I haven't pushed the car any. Well, I did once leaving a car show for a few Mopar guys , but beyond that, it's been under 3000 rpm. The car runs fairly cool with the 160 t-stat and reprogrammed fans, but just how bad is it running this lean? I haven't noticed any color changes on my headers like what's happened to my friend's LT1 before.

Jason

 

On my car I was running 14:1 on the dyno and thought oboy I would pick up some power with fine tuning. We got the A/F ratio down to 13:1 and lost 1 peak horsepower. However we did gain overall as the A/F ratio was smoothed out across the rpm range. You just never know. Allen

 

I'll take a 25rwhp LOSS than risk having to start my engine from scratch...

however, most Air/fuel ratio tunes will gain HP-- now, running very lean will usually result in a loss. Most cars tend to run rich instead of lean.

 

Well I got the graphs for everyone to see how bad they are. http://i2.photobucket.com/albums/y6/...Picture172.jpg


Jason

 

If you add some fuel you might see some extra power....but the real gain will be smoothing out the torque curve.