I have a 1.5L single cam vtec with an sfp turbo manifold, a t3/t4 .48/.60,and a tial 38mm wastegate. The spring is .5bar(7.3 pounds),but the car only hits 5 pounds and the wastegate doesn't open.. I checked for a boost leak and there is none. The engine just about shuts off when you cover the turbo intake. Has anyone else ever had this problem ?? do you have to break in turbo for alot of miles ?
Any help is really apreciated !

 

do u have an exhaust leak? that could cause it. also dont say there isnt a boost leak because u covered the inlet. pump the inlit with air so it builds pressure in the system with the TB closed n see if it holds it or if it leaks out.

 

also when your engine is running maybe your BOV isnt sealing and its letting some boost out?

 

No the bov isn't letting any boost out. Its a new hks ssqv. And if the engine stalls when you cover the intake on the turbo it cant have a leak because it cant suck air from anywhere.

 

And no it doesn't have an exhuast leak.

 

What kind of filter do you have on the inlet?

I had a few layers of thick screen over mine and it wouldn't allow enough air into the turbo to reach full boost... the symptoms were exactly what you described...

I would only see like 4 or 5 pounds of boost, which wasn't enough to open up the wastegate...

I replaced the screen with a real air filter and the problem was solved!

 

No filter.. That's gonna drive me crazy !