When choosing an external wastegate how does the spring pressure relate to boost going to be run. Just looked at a few on the net and Tial list springs from 6psi to 20 psi, so guess this is the v/v lift pressure so how do does this affect boost pressure.

 

They will release at what ever pressure range is available on the spring (you can fine tune the level you want via the bolt at the top) and then the exhaust gas will bypass once that boost level has been reached thus the turbo wont make any more boost.

 

Cheers mate new they acted as a p.r.v dumping the exhaust gass but didnt know if the spring rate was the same as the boost you want to run. Just wondered cause the ones i saw listed only had real low psi springs, but supose a lot will be used for turbo conversions on civics and stuff.

 

Anybody advise on what size to run on a cosworth, also who all runs them and what model?