rayS197
Senior Member
Brian, how much timing is the street tune and the race tune?
Instead of small plug gaps..like .024" - .028".. why not use higher voltage...like 30-40-50-60 kv...instead of the oem 20 kv ?? Then you could increase the gap by a substantial amount... = better spark.
Jimbo
I'm not sure exactly, Ray. Justin handles that aspect and I just let him do his thing. I know the race tune is still fairly conservative and there's room to add a few degrees timing when we go for the 700+ number. Street tune is a couple degrees less than the race tune.
I may have accidentally exceeded the speed limit ever so briefly on one open stretch of 4 lane road as well.
Damn criminal.
Not all the time, but yes.![]()
I already said it isn't plugs. Go back a page or two, it's been covered repeatedly. It's not coils either.
This firing miss is really beginning to bug me. My mechanic Alan said it could be a broken valve spring, and Justin agreed that was a possibility. Alan said I could pull the valve cover then take a hammer and punch and tap on the top of each valve stem/rocker. The valve with the broken spring would sound distinctly different. I did this to the best of my ability and couldn't find a broken spring.
Unsure of what to do next, I just put it back together again. Fired it up and it idled perfect. Decided to take it to lunch and a mile down the road it wouldn't idle again. Had to turn around and bring it home. Looks like I need to take a closer look at those valve springs. I borrowed a compression tester but it didn't have the right adapter for out tiny spark plug holes. Alan said he would order one from his Snap-On man.
I guess next step after the compression test is to take a closer look at those valve springs again. I wish I could post up the datalog sheet from the dyno. The misfires are very obvious.
Here you go, Gerald. This is from last Thursday. My mechanic Alan still hasn't gotten back with me about the 12mm adapter for his compression tester. I also have not yet received the valve spring removal tool which is being mailed to me. For now the car is running much better but still misses and stalls once in a while.
Since fixing the idle it hasn't done it much, and since tightening up the zip tie holding the electrical connector on the #5 fuel injector it hasn't done it at all. It would be really cool if that was all the problem is but at this point all I can do is wait and see.
I'll still look at the VCT solenoid the next time I have the valve cover off but I'm not going through all that until I have the valve spring tool. And to answer your question the springs are brand new springs from Livernois, the ones they use on the FRPP Stage 3 heads (I have no idea how else to identify them).
I dropped back down to the 11lb pulley on the blower because it's too much work trying to drive on the street with 640+hp. I'll still swap out pulleys for track days though.