WOT leaning with increasing IAT
Hi,
I have a 2008 6L Chev Lumina auto, identical to the Holden Commodore and the Pontiac G8, fitted with a Brian Tooley stage 2 LSA supercharger conversion, boosting around 95kpa. Internals are all upgraded including forged pistons with a 9:1 CR as well as AEM water/meth injection. Max power is 505kW and max torque is 875Nm. I tuned the car myself and it runs perfectly with a mafless configuration, but for one irritating issue, hence this post.
On acceleration as the IAT after the SC IC increases from 35deg C at idle to 41 deg C at 2nd/3rd shiftpoint/100 kph, to 50 deg C at 3rd/4th shiftpoint/154kph, to 54 deg C at 4th/5th shiftpoint/203kph, the mixture leans out significantly forcing me to run a super rich PE to protect the engine at the higher IATs. I've tried using the injector flow modifier vs IAT B1213 with no measurable effect. I suspect this table is not used by the ECM's OS 12612380. I run a 3.45:1 rear axle ratio and tuned out first gear completely, always pulling away in second to prevent damaging the propshaft or ripping out the backaxle.
I know it would be ideal to run a E67 ECM from a Camaro or Cadilac fitted with the LSA SC which runs with two IAT sensors to address the exact problem I have. Unfortunately, being old school mechnically minded, such a conversion, if at all possible, is beyond my capability with electronics.
Any advice or suggestions will be greatly appreciated.
