kulbordr

now this has probably been gone over time and time again but i cant seem to find anything on google for my setup and i wanted an opinion.
I'm turboing my car but i was wondering how to run my wastegate, bov, and boost gauge lines.
Now the guy that had the setup before me said he ran the bov to a t fitting inbetween the fpr and the intake manifold.
He ran the wastegate to one of the vaccum lines on the back of the intake manifold, and he t'd that off for the boost gauge now im wondering if thats right, and if it sounds legit cause i was gonna run it the same way.

Fabrik8

The gauge should come off of the manifold, because you want the gauge to measure manifold pressure (whether that means vacuum or positive pressure), and the BOV should come off of the manifold also because it is actuated by manifold vacuum when the throttle is closed. The wastegate reference should come from before the throttle plate, and you have a lots of options to take the boost signal from, such as the compressor housing, after the intercooler, close to the throttle plate, etc. The compressor housing is the easiest, and a lot of turbos already have a port for that purpose. After the intercooler is kinda nice, because the wastegate will be referenced to the boost pressure after the intercooler, which will compensate for intercooler pressure drop. There are some response tradeoffs depending on the different locations.

You don't want to reference the wastegate to the manifold side of the throttle body. Bad things can happen because you're referencing the wastegate to the opposite side of the throttle body than the turbo is on, and at anything less that WOT (wide open throttle) there is pressure drop across the throttle body. That means that the turbo could work its ass off trying to get to whatever manifold pressure you want, so the turbo could be putting out much higher pressure than the manifold (because of the drop across the partially open throttle plate). That means lots of heat is getting generated from so much air compression for absolutely no useful reason.

Oh, and if you reference the wastegate to manifold vacuum, you can completely destroy the diaphragms in some types of wastegates (many internal wastegate setups, for example).
Many/most diaphragms aren't meant to have vacuum on one side and boost on the other; they usually aren't designed for that type of force.
So just like anything else, you should know WHY you're doing something before you do it..

*EDIT*: I just looked at Tial's site and Garrett's site and they say to reference the wastegate before the throttle plate.

kulbordr

alright thanks for all the help im gonna have to figure something out for the wategate then cause my compressor housing doesn't have a spot for the wategate line

Fabrik8

Stop deleting the original content in your threads. All of your threads are completely useless now. I added the original content back in so other people could learn from common problems..