i'm wondering if anybody has tried running their wg off their turbo and off their im to see how different the pressure is? my intercooler is 24x7.5x3 with 2.5" piping. say i put a 8.7 psi spring into the wg. how much pressure can i expect to loose through the ic and piping?

 

It depends on the fmic's size/fin density, radius of your piping's bends, and the amount of psi you run. Its natural to have a pressure drop from the turbo to the manifold. Its going to be 1-3 psi if you're running low boost, and upwards of 5psi+ if you run 20psi+.

People usually run the WG off the manifold to get consistent boost. Going off the turbo is usually if you've maxed the turbo out and don't want it going past a certain psi.

 

i want to run 7-8 psi. i have a revhard manifold with a t3/t4 turbo. people who run their wg off their im have had problems with boost creep on the revhard manifolds, which seems to go away when run off the turbo (much smaller distance between vaccum source and wg).

 

i have my setup running off just the wg spring, and the source tapped into the intake piping right before the throttle body. reads fine, no spiking etc.

 

hm... i just tried running the wg off the turbo vaccum. with a 5.8 psi spring, the gauge read a little under 6 psi. the gauge is run off the im. is it possible to have no pressure loss or is my gauge a little off?