Gains?

[1G90AWDTsi]

how much hp am i looking at gaining from shaving the head (porting/polishing 3 angle valve job), opening the whole exhaust up to 2.5" w/ a resinator (no cat), shaving the block and boring .020? rough estimates?

 

[MrBoxx]

We don't do estimates here. That's known as bench racing. Since every car is different, there's no way of telling.

So dyno your car now, do your mods, then dyno it again, and you'll know exactly how much you gained/lost. Anything else is just numbers on the screen.