ok im confused here. now the wastegate is fully open at idle because of vacuum. but when the turbo hits 5psi is it vacuum or pressure in the manifold that pulls/pushes the wastegate open??

now if i have a vacuum pump. if i pump it up to 5psi vacuum the wastegate should open? 5psi vacuum = 5psi boost?
i am so confused.


[Modified by shortyz, 6:28 PM 1/12/2003]

 

When you are dealing with wastegates you are dealing with postive pressure in the lines. If the wastegate spring is at a stiffness where 5 psi (pounds per square inch.. pressure) can compress the spring, the WG diaphram will open and let excess exhaust out in order to help control boost levels.

Vacuum is not measured in PSI, as it is an absence of pressure in the lines. You could attach a vacuum pump to the system and you would be unable to get the wastegate to open. However, attach an air compressor to the system and you will be able to open the wastegate as you are introducing postive pressure into the system.

 

uhm this one i got when i hook it to vacuum at idle it pops open.

 

are there two ports on the wastegate? it should be held shut with spring pressure at idle and open when the air pressure from a boost source reaches the pressure that the wastegate is designed to open at.

 

theres 2. ones threaded. whats what.

 

lol wow i have a built sohc and a built ls and im working on a dd sohz zc on 8 psi and cant remember how to put the valve seat in wow lol lil help or il take my other one off and look at it

 

^^^^valve seat in the wastegate

 

WG is supposed to see pressure, i believe i have seen TIAL themselves post stating that if you hook it up to vacuum it may still work but could tear the diaphragm.