I had a high rpm miss issue that I thought I fixed. It would fall on it's face around 5000rpms. The problem happened all of the sudden, there was no miss and then 5 seconds later there was a obvious one all the time. I swapped coils and ign modules with an extra I had, and it had no effect. I then replaced the plugs and wires/coil wire. Took it out for a drive and it still sounds like it's missing, but it doesn't feel like it. It pulls pretty hard up top, but has an obvious stuttering sound. There are no trouble codes, and the scan shows a smooth rpm all the way to 6000. I'm running about 82% duty cycle at 6200 on the injectors. Fuel pressure looks good. The opti has about 6000 miles on it and the O2s have about 25000. I am seeing some knock but nothing to make datatmaster show any yellow or red flags. The stuttering sound only occurs under load.

Any suggestions on what this could be?

typical 94 firebird heads, cam, longtubes etc



and yes I've just read through an hours worth of posts that I looked up.