i just had a pnp head with a slightly pnp blower, put on with a 2.7, and dual pass. my old setup was a 2.79 boostin at 16ish w/ boltons in sig. im peaking 17.5 psi now(both interceptor and stock gauge read the same). this doesnt seem right to me, i should lose boost right? i just hollowed out the cat and no difference, btw the cat was not clogged. but the car pulls harder then ever, iat2's stay around 135 under load, afr stays in the 12s. maybe its fine but iv heard a 3psi reduction is the norm on a pnp head.

 

boost loss is a matter of how much was removed from the head apperantly all you got was you port polished with very minor removal of metal from the head

 

i understand head porting my best friend is the owner of headgamesmotorworks and my sister works for him. my other friend Recklessactn got a head done by him aswell (a little less aggerssive) and saw the boost drop 3-4psi. mine is port matched and very aggressive