i know with a turbo a test pipe can cause more boost,but what about a supercharger?

 

if the test pipe lowered restrictions in your exhaust, your PSI guage will actually register lower than before! This is because the overall efficiency of the system has increased, and there is less resistance post exhaust ports! The reason a turbo can over boost is because the exhaust gasses follow the path of least resistance, and the lowered restriction from the TP makes the gasses more likely to flow through the turbo instead of the tiny internal wastegate!

 

Increasing quality of air flow on an SC will lower boost. But lowering boost isn't a bad thing. People who get headwork done will often lose boost pressure, but gain horsepower.

Making more hp with less boost = major win. I'm not sure how much of an affect a test pipe will have though as that is the exhaust side. Hopefully Sideways or someone else can clear this up a little.

 

when i had my stock cat. and a 3" exhaust i read 10.5psi

when i installed a test pipe i went up close to 13psi

 

Is that with a turbo?

 

Looking at the car i would say thats a Comptech Charger he's talking about!!

 

Comptech makes a lot of parts for S2Ks. I have never seen a test pipe raise boost on a CTSC. Centrifugal SC's boost pressure aren't affected by back pressure, or at least thats what I thought.

 

so what size pulley do you have on the charger?

 

anyone else?

 

with a vortech the tp will make good gains but make you run a bit lean on black box.