Pressure drop question

[ATLGt]

I have .9 bar (~13psi) wastegate springs set up in my wastegates. The problem is I am getting only about 10 psi at the intake manifold. My vacuum line to the wastegates come from the fitting on the turbo housing. Is a 3 psi drop common over the intercooler and throttle body? I would hook it up to the intake manifold, but I am out of fittings and I don't want to run a double tee off my MAP sensor or boost gauge line. Comments?

[patrick4588]

thats a big drop man, what kind of intercooler do you have and have you pressure checked the system for leaks?

[ATLGt]

It is an Apexi core. I have not done a pressure test. I was looking at getting all the pipes welded and this may be the time to do it to see if that fixes the problems. I can get some Snoop from work but I really don't feel like removing my front bumper to check all the welds. I may just hold out till the summer gets hot enough that I don't drive the car.

[turbob20]

maybe your waste gates sticking or not seating properly. do you have the valve seat in the bottom of the wastegate? its a round ring that sits in tye bottom of the wastegate.

[Bacon]

This is a slightly difficult problem to figure out with very little info. What is the setup? Twin turbo, single turbo, S/C etc.? What kind of car? How much boost total? Let's get a little more info and we can go from there. Here is my thought.



I have .9 bar (~13psi) wastegate springs set up in my wastegates. The problem is I am getting only about 10 psi at the intake manifold. My vacuum line to the wastegates come from the fitting on the turbo housing. Is a 3 psi drop common over the intercooler and throttle body? I would hook it up to the intake manifold, but I am out of fittings and I don't want to run a double tee off my MAP sensor or boost gauge line. Comments?


Wastegates? Assuming this is a TT setup.
psi loss - there is a loss in pressure with the charge piping and IC. depends on how much boost you are running.

[turbomirage]

His set-up could be twin-turbo, or he could be running a divided T4 set-up. I would recommend running the boost gauge vacuum line from your compressor housing. I would also recommend running your WG's/boost controller vacuum line from your intake manifold. You will have a much cleaner vacuum source when running it from your intake manifold. Ideally, you would want to run all your vacuum sources from the intake manifold, but I know you had mentioned you cannot do that. Other than this, I highly recommend a boost leak test. Does your boost gauge needle flutter when you are in negative vacuum?