So I am playing around with and still learning how the Gen 5 engines tuning works. One of the questions I have is derived from a new change I made to my setup.
Car is a 17 Camaro SS M6 with a Procharger D1SC at 10psi. I have catless headers into a AWE Touring axleback system. Car has the full LT4 fuel system (LPFP, HPFP, injectors, and all of the LT4 fuel lines). As of now the car makes 640rwhp on E35-E40. When the PC setup was put on the car the shop put on a Alky Controls dual nozzle meth injection system. Originally the car made 650rwhp on 91 with the meth inj system, then I swapped in all of the LT4 stuff and had the car retuned by another tuner, he fixed tons of things wrong with the previous tune. The car runs great with zero issues at all, never sees any knock at all.
So after spending some time on the phone with the owner over at Alky Controls I went the route of re-purposing the meth inj system to use it as it was intended, to cool the air charge down. I used a DSX IAT/Baro break out kit and moved the IAT into the intake about 2" past the throttle body. I am running a 50/50 mix of VP Racing M1 methanol and distilled water.
The logs look great, fuel pressure on the low side is 73psi and the high side is a little over 26xx psi. The A/F was commanded for .83 Lambda and came in at .80 so it is a little rich. Normally I know to correct that is a minor adjustment with the MAF calibration (airflow vs. frequency) table. Here is wherein my question lies.
Is there a PE/WOT Lambda ratio for gas and then for E85? I guess my question is how is commanded Lambda for gas and then E85 determined? In this case with me using the meth inj to cool the intake charge down it is throwing the commanded A/F off and making the car richer. So do I just adjust that thru the MAF calibration or is there somewhere else I need to be making corrections at?
Todd