I'm experiencing a random high rpm miss between 5000 & 6000 rpm. The motor cuts in and out like it's against the rev limiter, missing fuel or spark. I know this isn't the rev limiter (mines at 6900), but that is how the engine reacts. This happened three times at the track yesterday in 2nd and 3rd gears (only made three passes). On the drive home from the track, I ran thru 2nd gear twice with no missfires. This morning I pulled the plugs, wires, and coils to inspect and everthing looked fine. I don't think I have a fuel issue as my AFR is consistently 12.6-12.8. I'm wondering if I'm having an issue with the crank or cam position sensor. I've checked all the connections and nothing out of the ordinary. No DTCs have been set in the PCM.

My setup is a follows (only 1000 miles on motor):

402 LS2 - 8.4:1 (Callies crank) Currently running NA
TR5 gapped @ 0.040, Moroso wires
42 lb injectors, 255 lph pump

Any thoughts would be appreciated!

 

T T T

 

Don't know if this helps but try using the stock Iridium spark plugs. I used the cheaper bosch type and had a spark problem for some time. I removed them and used the more expensive but better performing GM part. Just my 2 cents experience.