soundengineer

iTrader: (16)

so I have tuning...but I'm pretty sure our part throttle tuning is fixed at 14.7:1....
right????

so is there any way to richen up the part throttle??? get it a little closer to 13.3:1 or so???

I know it reads the o2's at part throttle and ignores them at WOT...

so can we put in some kind of resistor?? or is there a way in Ls1 Edit to take care of it....

Cal

iTrader: (1)

Why would you want to? Your engine will just burn more gas. The PCM will make it richer than 14.7 at part throttle under high-load conditions anyway. PE is used in several cells, not just WOT.

soundengineer

iTrader: (16)

If I was worried about burning gas...I wouldnt have bought this car and done what I have done....
I'm just thinking on the driving around town Idea...If we racec at 13ish A/f for best power...and I wasn best power all tha time..not just when I stomp on it....why wouldnt it make sense to richen it up a little...maybe not as rich as WOT...but definately a little....and when you let off...you wouldn't get such a big dip in the A/f....it would stay more consistent....and you would have less dangerous lean spikes on the street...have you ever seen an a/f printout from a wideband on the street???
not good when you let off tha gas.......many times it goes dangerously lean because it cant correct fast enough and it overshoots 14.7:1 ....

Cal

iTrader: (1)

Yeah I've seen it, I have a wideband. I don't think those lean spikes mater since the throttle is closed and the injector pulse width is very narrow when it happens. But if you really want to mess with this, I sugest you use the VE tables to do it. VE in the LS1 seems to play into the transient throttle response.

Slowhawk

iTrader: (12)

Remember those lean spikes are reading exhaust gas flow So less flow means a leaner A/F reading.A 15-1 A/F at part throttle gives you more power than 13-1.Your engine can run 18-1 in a low load situation without any damage to the motor.

Colonel

I would think plug fouling might become an issue with a constantly rich mixture.

I would think part throttle responsiveness, power, and MPG would be LESS with a mixture much richer than 14.7:1.

If you need more power at part throttle, I'd suggest using more throttle.

Colonel

...But, I'd curious to see what would happen if you changed the "Stoich Ratio" in the fuel tab to a value less than 14.73684210.

Billiumss

iTrader: (11)

Don't take this the wrong way, but why would you want to do this? GM engineers spent millions on getting the tuning right on these cars for part throttle, I doubt you could do any better.

BTW - Your car goes WOT once you get 75-80% throttle...

Richard@WCCH

iTrader: (3)

Colonel: I've wondered the same thing. One of the problems with doing this are the O2 sensors. Changing from 14.7:1 to say 13.7:1 upsets the switching in the stock narrowband sensors. I'm guessing the PCM would no longer recognize the symmetrical voltage output and that would decrease the accuracy of achieving the target AFR. Still, I'd like to try it one of these days just to answer the question.

Of course if burning gas isn't a problem, why not unplug the MAF and tune the MVE table for AFRs other than 14.7:1?

Richard