to prevent boost creep or over boost on a long runner turbo manifold is it possible to have two waste gates? like say one internal one and an external one?
I dont know...
I do know of some cars running 2 wastegates but they are running over 35 psi usually... I would think that up to 30 psi which I doubt you'd ever hit you'd be mroe then fine with 1 wastegate
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I've read up some on high boosted cars with it but if you get boost creep and you need to get more exhaust out fast enough then wouldn't you be able to do it? i am getting a internal waste gate t3 turbo. dont know if it will have any boost creep or over boost but if so i want to know i can get ride of it.
I would think all you need to do is have a T fitting for the vaccum lines to split off to the two waste gates. But maybe im thinking wrong.
yes having 2 wastegates is possible. Is it worth having two for your specific reason no. If you want to use to wastegates such as one external witha dump set at a higher psi and having an internal for low boost. All you would need is a 2 way valve and some interesting vacuum routings. isnt a hard concept but two for your purpose not really worth it. If you have a proper functioning wastegate shouldnt spike much unless you get into manual boost controllers. How much boost do you plan on running? I was told by someone the other day that they wanted their internal gate welded shut and to use an external wastegate instead which in my opinion was a waste of time. If you take the boost line off the wastegate the turbo will spool as fast as the exhaust gas can push it but if you have an external you wouldnt have to worry about the internal gate because the external would be regulating the exhaust flow around the turbine. He wanted to go to external with a dump and if anyone has done this they know how extremely loud it can be and how much it can get you into trouble with the law enforcement officials. But if you have a valve you can go from 7psi internal gate, flip a vacuum switch and run boost to the external gate and have say 14-15psi spring with a dump tube so you can be loud and fast. I wouldnt worry about a problem that you dont have yet.
*2012 mazdaspeed3*
