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Does anyone have a technical description of how this 2 stage boost solenoid actually works?

If the 2 stages are say 5 and 7 psi, does the wastegate act at 5psi, and at high rpm the solenoid bleeds off boost to allow up to 7psi boost but 5 to wastegate? If it worked like that then then removing the solenoid would give you 5psi throughout the range not 7psi.

What does it do to control boost?

Do'h,

I should read your post all the way through.

The problem with the factory solenoid is that it is modulated to bleed off excatly 2psi more, it's not just an open/shut affair.

And if you unplug it, or by pass it you'll end up with 5psi not 7psi like what your after.

The only save way to get a constant 7psi is to get a bleed valve or even better, a EBC.

I've heard of people pricking holes in the wastegate hose with a hot needle, but I wouldn't be doing this !!!!

J

A cheaper option is to get a brass needle valve tap (I think that's what there called) Now remove the solenoid and plumb the hoses into each end of the tap, you now have adjustable boost control (open to increase boost) that won't spike like a Turbosmart BC, and your A/F ratio won't be upset cause it's still venting off into the intake pipe (will still be rich though, but not more). Incedently my car used to run 7 then 9psi stock, with big exhaust.

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