(Yes I did search)

Still don't have an answer....



OK, I have just installed a new turbo setup that uses a Tial wastegate. I have connected the WG as per all the recommended connections per this thread.

https://www.evolutionm.net/forums/sh...ate+restrictor

and this pic (with one side of the boost solenoid to atmosphere)



So, here starts my trouble. I tried to boost leak test the system before I fired the car up. When I did put air into the system... it just blew out of the exhaust. Is there a trick I am missing to boost leak test with an aftermarket wastegate??? I did put the crank TDC and it didn't make a difference. I tried moving the WG vac line to the top port and no change. Put back on the side port like it should be and no air is leaking out the top port which is left open to VTA.

Does anyone know how to test this different? Better? I don't want to cap the Upper IC pipe at the throttle plate... I would like to test the system on the car all the way in. Does the car need to be warm? Oil and coolant was drained and the motor was cold. Could that be my problem?

 

where exactly did you attach the boost leak tester to?

 

looking good

 

huh?

 

I attached it to the air intake on the turbo. Pulled the airbox and attached a coupler with a cap right on the compressor side of the turbo.

 

thats strange... from your description it sounds like you hooked everything up correctly.

Rotating the engine should not make a difference, as long as the throttle plate is closed the system will stay pressurized.

 

I will try to run the car and see what it holds as far as boost on the street 0 psi or 17 psi (WG Spring). Maybe that will help???

 

i was actually going to suggest that. If it makes boost on the you should be able to simulate it with a boost leak test... otherwise something else is going on.

 

with the throttle plate closed it will not stay pressurized. that why there is an idle bypass, so when the car is running even with the TB plate closed the car will run. you need to have the motor turned to a spot where the valves are sealed. you can tell by turning the crank over until it begins to get hard to turn. that is a compression cycle, leave it there and repeat the test.

 

LOL, here is a 5 minute drawing of how I have everything hooked up....

I miss my Visio at work. My drawings were so nice with it.

 

I tried that before TDC. No change either way. My BIG question is if an aftermarket wastegate will boost leak test like the stock config? Just presure up thru the turbo to check. I tried it on one other car and it blew out the exhaust but that car ended up having a bad wastegate too. I am wondering if I am going to be in the same boat?

 

unless your TB seals are leaking the system will stay pressurized with the TB closed. You do lose a slight bit of air through the plate but it shouldn't be much. This is how I've done it on the EVO dozens of times as well as other turbo cars I own. TDC doesn't make much difference unless your doing a 'leak down' test.

 

can you add to that diagram where you placed the leak tested, just to be sure.

If everything was setup correctly you should have had air leaking out of the port you have tagged "airbox side open to VTA". You should actually plumb that port back into the intake after the MAF, but before the compressor inlet, since its metered air your venting off.

 

I have attached the diagram.

That port of the stock boost soloniod does go to the stock air tube between the MAF and the compressor side of the turbo. The air in there will NOT hold pressure. It is not an air tight part because of the filter. That port is just a filtered air source at 0 psi (right?). The new intake tube with my kit doesn't include the nipple for that line. So, I left it VTA and we checked it and no air is escaping from that port and no vacume either.

 

everything is hooked up correctly to do a boost leak test... take it on the street and see what happens.