I was thinking a NapZ block with L20 head for better breathing and it would still match up to trans,,,,,,
BUT,, since i now have read he can`t legally change much of anything emissions wise ( I live i Washington so i have no idea what you can change )
i would just lower it a little and get some wicked rims and tires ...then lower it so more..
My old 510 ain`t fast it`s a Datsun