"..and have done many works on an evo....the shoped as 2 500whp evos...."

Please show some mercy for the English language.

 

Its the MBC. I went threw 2 turbosmart MBCs thinking it was just a defect. Its a crappy piece and I would move to a forge or hallman if your going MBC.

 

I am not saying that 22psi is the magic bright line test in terms of engine knock, but as a general rule of thumb, it's a pretty safe limit to set for someone who relies on a "shop" to tune their car for them and probably do not have on road diagnostic tools like a wideband 02 gauge, EGT gauge or even a datalogger.

21psi is safe on a 9:1 motor. I'm just trying to scare the kid into fixing his car. Thanks for the help, though.

Doing the "drag race test" is NOT good enough. My suggestion is to get on the highway, put the car in 4th gear at 2500rpm and bury your foot in the throttle. Use this as your threshold. The car won't move at first, but then you'll see a cute boost spike. Make sure this stays around 22psi or thereabouts and you should be safe. 25psi sustained on pump gas as max cylinder pressure is NOT a good thing unless you want to know what the inside of the block looks like.

 

im good now..i figured it out...just went driving and from 3rd gear about 2500-3000rpms i spike at about 21 PSI and from a dead stop at 1st gear im keeping about a constant PSI at about 17-19..im good now..thanx every1