Can't Build boost powerbrake

[matt921]

So over this weekend I had my turbo go out. So I swapped to a 87 gn turbo and had my buddy weld the coupler to the inlet of the turbo. I posted pictures so you can see. But here is my issue. I got it all together and started. Drove it and it seemed to take for ever to build boost.. How idk its the same exhaust wheel from the two 84 85 turbo to the 86 87 I think it was 2.30 and the same size exhaust housing. I have no exhaust leaks and a new 02 sensor. im pulling 11hg in drive and about 14 15 park. I have pulled the turbo twice thinking I had a leak on the intake to turbo. It seems to be snug in there and not leaking. I have gone over my vacuum lines and I cant find any of them to be wrong. I drive it and it will hit 10-11psi but when I powerbrake i can't even get one pound. Could there be something that Im not thinking and looking over.

 

[matt921]

Here is the pics

 

[Jerryl]

What converter is in the car? Had the same issue when we fist purchased the car. Would not spin regular tires on wet pavement. Converter stalled 0/0 at 1600 rpm.

 

[matt921]

It's a stock convertor. But before when i had the original hot air turbo i could get 10psi on a pb and it would spin the tires. Now i cant even get one. Today on the way to work i would give it gas and it seemed like a huge vacuum leak an the car would hesitate and once it stalled. I am printing the diagram out for the vacuum lines to see if maybe there is one i missed or misplaced.

 

[matt921]

So started doing some measuring and close look at things. I found that even though the two exducer wheels are the same diameter the profile of the wheels are different thus making the housings a little different. I first had the 84 housing on the 87 turbo and it would boost for beans. Then i put the original 87 exhaust housing on and whabam boost like theres no tomorrow. I had to turn my wastegate out a few full turns hahaha. But as for power braking it is building boost just takes a little longer then the orginal hot air turbo. So in the end im very happy with this turbo upgrade thanks everyone.

 

[bison]

The turbine wheels are not the same and the ex housings are not interchangeable between the 84-85 and 86-89 LC2 engines.
Posted before reading your last post

BPE2013@hotmail.com

 

[matt921]

Had to learn some how lol. Atleast it was on my car and not a customers car at work