Okay I just built my head over size valves, retainer, springs, P&P. I have 255 pump, stock injectors, and a FMU 8:1. I my cars fuel at idle is 40 PSI and rockets up to 70 to 80 PSI in 7 lbs boost. My air/fuel spikes rich as it always has in boost, but ss my car climbs into the higher RPM's it begins to leanout. Help what going on?

 

Swapped out my stock injectors w/310's and it works fine (bad injectors). Fuel pressure is a bit higher now. Going to switch to a 6:1. Thanks but no thanks for the help? I have a set of DSM 450's and SAFC on order.

 

Trusting in your A/F gauge eh?

Stick a wideband on it and get an accurate measurment.

 

or at least get an egt gauge. never trust a rich lean gauge.

 

Yeah I know A/F is crap and I know better to tune off of it. But when you drop a lot of money for things not to go right well... Anyway I friend lent me his spare 310's and that seem to work. I'm still open for good idea's on why this might or might not be the prob.