my stock twins are rebuilt, but the 2nd turbo which is on when is 4500 rpm, but it doesn't work? what's wrong with it? please help

thanks

 

http://www.autosportracetech.com/RX-...leshooting.htm

 

There is probably nothing wrong with the turbo, but instead the turbo control system. At 4500rpm, the secondary turbo comes on line, and several control components activate simultaneously. If any of them (actuators, solenoids, pressure reservoir, vacuum reservoir) have leaks or failures, the secondary turbo's output won't get to the engine.

It may help to understand a little more of what's happening:
http://web.newsguy.com/geesaman/TwinTurbo.PDF

Follow the link Mahjik provided and you will find out about all the control components you need to check to get things working right. Odds are that you just have a loose air line.

Dave

 

probably a popped vacuum hose, check for a vacuum leak, did you do the siliconne hose job?

 

thanks for help

 

particularly check the 4 vac lines under the crossover pipe.