Just wondering if anyone has actually tried richening up AFR's in PE when tuning for max tq?

Stock AFR's on C5's are rich to begin with but do follow a path of rich to richer in the 4400-4800 rpm range and then lean out again. The fews tunes that I have seen are pretty much flatlined @ 12.9:1 or so in PE.

 

From my DIY tuning adventures (I haven't dynoed, but I get good response)...

 

I'm not saying that theres not optimal AFR's for differnt parts of the RPM band..

But have you considered that torque is a function of power? Alot of guys say something like XX most torque while XX makes most power.. Not possible.. If torque in that spot goes up, power goes up in that spot.

 

Joecar:

I set my PE in a simliar fashion. GM obviously does a similar setup as well for a reason.

I hope to get back to the dyno in September or October and play around with the different PE settings.

 

Going from a flatlined 13.0 to a little richer mixture through the TQ definately imporved my 60' and 1/8th mph

 

i got about 350rwtq peaking at 0.78 g/cyl, that's about 4.5lb/tq per 0.01g/cyl which is the smallest amount loggable, so you wont see any changes smaller than that. changing my AFR about 0.4 made 8rwtq difference so the resolution isn't the greatest as far as tuning is concerned, but it is possible to see significant changes in dyncylair.

 

Let me know how it your PE end up.

 

Joe are you running the stock cam with this pe modifer? i'm running a almost flat pe modifer of 11.79 - 11.70 afr above 2800 rpm

i'm going to give yours a shot tomorrow and see how it responds

 

Yes, stock cam; this is my enable:



Let me know how it goes; if I missed it, what car do you have...?

 

My major mods are listed in my sig, 98 z28 w/3.23's Yank 4400 and a build by ME Trans and at this time I’m running all stock internals. I have this bad habit keeping everything I order in boxes.



My car seemed a little more responsive at lower RPMs in PE but WOT was hard to tell… and my LC-1 is still off for warranty work so I’m not sure what the AFR was… I think the LC-1 will be back by this weekend and I might make it to the track to see what it does vs. my old setup.



What inspired you to change your PE modifier like this? This is one of 1st I have seen like this.

 

I use PE to arrive at my preferred AFR when I am threatened!!