Rb25 misfire

Hi my rb25 has developed a misfire, seems to get worse with heat. It runs e70, yaris coils and ngk bcpr7es sparkplugs. Link ecu. 30 psi boost, 600hp When i drive in after 1 lap i can take connector off coil 6 and 4 and there is no difference in engine tone. If i leave it an hour to cool it seems to be ok for a very short time. Any ideas what could cause this guys?

Also have done compression test 150 psi on all cyclinders

Hey Joseph did you resolve this issue? Do you mind sharing your findings?

Indeed, would have expected a follow-up with coil, and then injector, swap arounds.

It seems to be an over-heating issue of some kind.