GEN 1 P0300 Random Misfire

I started getting this code at WOT about 2 weeks ago. Had all the plugs checked and regapped, all wiring seems to be good.

I've seen others have this problem and the only solution I've found is that they stopped running at WOT. I enjoy this truck and enjoy running it, don't want to take my foot out of it at times.

Truck has a roush sc with 650 JDM tune, 65 mm throttle body and full Kooks exhaust.

I have spoken with Jim at JDM and he has worked with me to try and see what could be causing it but it hasn't resolved the problem. As there have been others with the same type of issue that weren't supercharged I don't believe it has anything to do with it or the time.

Anyone have any ideas?


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Heres the list of possibles:
Spark plugs that are damaged or worn
Spark plug wires and/or coils that are damaged or worn
Fuel injectors that are defective
EGR valves or tubes that are clogged
Ignition timing that is off
Vaccum leaks
Fuel pressure that is low
Head gasket(s) that are leaking
Coil on Plug failing
Camshaft sensor that is faulty
Crankshaft sensor that is faulty
Mass air flow sensor that is faulty
Oxygen sensor that is faulty
Throttle position sensor that is faulty
Catalytic converter that is faulty
PCM is faulty

Now having posted all that I highlighted two. I don't have the mods you have but that is how mine started till finally the Check Engine light stayed on and thru out the P0308 code for #8 COP Bad. You could have another, 1-7 but the 8 position is common. Or you could just have a timing issue at WOT that could be adjusted by JDM