Hi, i'm having my 95 RA's engine rebuilt, and am changing the heads for STi V3 heads. I understand they are better, with hotter cams. Will i notice any difference with these?

Thanks,Mit

 

Largely depends on your wilder cam's duration and lift.

The solid lifter STi 3 heads will allow the engine to breathe so much better the the hydraulic v.1/2 ones. The early WRX heads apparently suffer breathing issues and can surge at around the 380+ bhp point.

The STi 3 heads apparently can handle at least 480-odd bhp. Remember to get some MLS HGs in there too, such as the STi 3/4 ones (1.6mm thick - to keep the same CR).