how do u do a boost leak test? im trying to find a compression checker i can borow but no body has one some im probably just going to go buy one...

 

they sell them but you can make them from a pvc cap and rubber radiator hose goes on the tb. and pvc cap glued to the hose and a hole in the cap and jbweld in a 1/8 pipe thread air valve (style so you can use an air compressor.) and then you connect this to your throttle body and compress the system- if you are lookin for leaks between the tb and head. or put it on the turbo inlet. and listen for leaks and feel. or use soap/water for the rest of the system- turbo-throttlebody. idk there prolly are different ways but this is how we do it. we found interesting leaks.. so it served its purpose

 

A bad head gasket can cause less boost. Here is why.

When a headgasket fails, in some cases you will loose compression in a cylinder or multipe cylinders. That cylinder is now basically dead weight because it isn't producing any power. Now think about how a turbo operates. The exiting exhaust gases pass out of the head, into the manifold and through the turbo. Before your headgasket failed you had 4 cylinders flowing into your turbo. Now you have 3 or maybe 2. This means that you only have 3/4 or 1/2 of the exhaust power that you used to have, therefore your turbo may loos power.

This may not be the case, but it is definitly a possibility.

 

i got this from ebay to good price..