I Have a stock BB DET

Well I was wondering. What keeps the engine from boosting when you're stopped. when I floor it the boost gauge reads 0 and won't boost.

This got me wondering. I know when you launch the car you want to time the pulseing of the thottle so that it reads 0psi when you go.


Just a dumb ???????
nothing big.

Turbos work off exhaust gasses created from an engine under LOAD , when you are stopped at a light, and you floor it as you say, it will not boost because your engine is not under load. If you bounce it off the rev limiter you will build boost but I wouldn't recommend doing it. If you want to build boost on the line, you can always get a dual stage rev limiter, that will help you out; I wouldn't recommend it unless you want tranny issues.

Originally posted by body80
I Have a stock BB DET

Well I was wondering. What keeps the engine from boosting when you're stopped. when I floor it the boost gauge reads 0 and won't boost.

This got me wondering. I know when you launch the car you want to time the pulseing of the thottle so that it reads 0psi when you go.


Just a dumb ???????
nothing big.

The turbo will make boost when the exhaust gases are sufficient to "spool" it up. For example, on a T25, if you're over ~2500rpm the turbo is spooled and making boost. However, the bypass (BOV) valve won't close unless it senses engine load. You won't get boost to the intake manifold until the bypass valve closes. My bypass valve closes when it senses manifold pressure greater than ~10in.hg, then pssssssshhhh goes my SR20 :D The wastegate sets the maximum boost. If you're intrested, the book Maximum Boost does a fair job of outlining the basics of turbo systems.
Cheers,
Charlie :)