Parish what was your ignition problem?

GMC SKI May sound like a stupid reply but what is your spark plug gap? Try narrowing it a bit... May sound crazy but fixed my high RPM miss... Extra boost needed smaller gap.. Just a thought..

Parish what plugs and gap do you run?

 

My plug gap is .55 is that too big ?

 

i am running ngk br7ef plugs at the gap they come out of the box, i think it is .025.

i am 99% sure my top end mis is caused by lead fouling of the plugs. i a running leaded fuel and there is some info out there about the subject. to fix it i run new plugs before any event. they seem to last at least 1000miles on the street but need to be prety fresh if i am going to open the exhaust and crank the boost. it may not be lead related but some other plug problem but new plugs seem to fix the problem.

 

did you mean .35? .55 is huge for what you are doing.

 

I meant .65 .... really no I'm at .35 Seems to work well for me at the power level I'm at right now Never had the issues dyno three times before with the same gap
made near the same power with a flat HP and TQ curve
So i'm gonna try out a new set of springs
I have about 10k on the current ones that are rated to stand up to a .620 lift the cam is at .600 so i think they may be a little tired