I have a set of Delphi/Lucas 42 lb/hour injectors ( rated at 43.5 PSI)

currently my injector constant is at 42.435 in LT1 edit and Stock injector offsets.

IS anyone runing a different constant with these injectors?

The only thing that I have been strugling with my car is the idle fuel, its too rich. My engine builder says the 260/260 @ .050 solid roller cam is the culprit, and that unburnt fuel gets past into the exhaust do to the low efficieny of complete combustion at low RPMs because my cam is so big.


I have tried lowering my MAF tables, that just caused stumbling and the car wanted to stall liek it didnt ahve enough gas. VE tables do the same thing. are my injector constants/ offsets wrong ?


Or is he right that my cam is just too big to ever cure this problem ?

 

I am running stock offsets in my blown LT4 396 Vette, fuel trims are nearly spot on with a 224/236 Comp cam.

 

Start playing with the injector offsets between 12.0 and up voltage.

Here's a table with the offsets for them to start you off.
http://www.carprogrammer.com/Z28/PCM.../injectors.htm

My setup is running about 15 to 18% rich at idle and I need to play with the offsets to bring it into line next week...

Mike

 

I'd recommend using constants to adjust fuel, and leave offsets alone. Use offsets as a last resort, or for extreme fine tuning after exhausting tuning with constants.