turbo80cid

I’m tuning my LT-8 for emission testing but I can’t seem to get the idle AFR leaner than 13.5. I have not touched the factory timing settings yet but I was wondering if I could run more advanced at idle and then lean out the AFR closer to 14.7? I’ve only done a rough tune in the NORMAL mode and now I plan to switch over to MATRIX mode.

Also I’m leaning out just before 3000rpm’s. I think I need to up my %stage from 50% to 65%.....will that help or should I just tune that out in the MATRIX mode?

Engine specs:
Stock S5 engine (stock ports)
Stock turbo & intercooler
Stock 550 primary injectors
720 secondary injectors
Idle fuel pressure 38psi

-Bill

Radial GT

iTrader: (16)

Run an airpump into your exhaust. Run the gas tank low and put a couple bottles of rubbing alcohol in there. And a cat.. or 2. It was TOUGH getting mine to pass. Oh and make sure your out giving it one hell of a good run before you get there to have the turbo cook'n.

RotaryEvolution

iTrader: (30)

rotaries do not like to idle under 12.6AFR, you are misunderstanding stochiometric values, those are based mainly on piston engines and for cruising light load applications.

with a good catalytic converter and airpump blowing on it then toss AFR values out the window, lean it out til it just starts to want to hunt/misfire/die at idle then richen it up a tad and that should be good for emissions testing basis.