93wrx, boost at 1 bar, full decat hiper

tried flooring it yesterday and hesitated in almost every single gear above 4k rev!!! it seems that there are those "pops" in the exhaust every gear change and had a massive, i do mean MASSIVE LOUD
pop once from 3rd to 4th.

any ideas what the problem may be?

 

Warm at the moment?

 

Mis firing? - Spark Plugs failing or your leads breaking at high RPM.

 

engine warm. plugs r new hks irridium.

will try another run tonight again

cheers