range hadies

A friend of mine is attempting to turbocharge his 06 civic si, how much pressure can they hold or better yet what kind of hp can they handle with stock internals. I know b18 can do 10psi or 300hp shouldnt a newer and bigger engine be able to do more?

vladd

PSI doesn't mean anything, as different pressure levels on different sizes of turbo create different amounts of power. I've always heard 350-400 WHP is about the limit on stock K20s if you want it to be a reliable DD. I'd spent some time looking through the forced induction forum.

spdrmn

also depends on the turbo use and the kit. i know some people that get up around 375 on 4psi and up to 450+ on 11psi. anything up to 400 is ok on our block from what i understand. when you go over that you wanna start getting supporting mods. from my research its usually the rods that get done first as they are more prone to fail and cause irrepairable damage to the motor at high power. im not boosted yet, but will be soon. ive already built my motor up to support around 500hp, though i will not be using that on a day to day basis.