Hey I have 88 turbo II. And I noticed that my car pulls very good when is on boost but in higher gears I can see the boost gauge dropping down. The previous owner of the car said the turbo was freshly rebuild. It even has S5 trim (that's what he said) so my guess is that there is a boost leak? Where should I look for it? Is there a common place for that issue?. Or simply the previous owner lied and the turbo is bad.

Funny thing the car doesn't smoke at all ( which I thought that if the turbo was bad it should smoke a little due to bad seals).

So please any help would be greatly appreciated.

Oh and one last question.

CAN THE LSD ON THE 88 TURBO II BE REBUILT??? or should I just look for aftermarket? ( or just weld it??)

 

What is the peak boost level you're seeing, and what does it drop to at high RPMs in 3rd/4th/5th gear? In stock form, you should see a pretty solid 6 psi by 3500 RPM, and it should hold it nearly all the way to redline. It might drop off a psi or two by 7k.

If you open up the intake and exhaust, you can squeeze a little more out in the top-end. For instance, on my car I see 12 psi peak at about 3500 RPM, and it will taper off to about 8 or 9 psi by redline.

The stock turbo is fairly inefficient at higher boost & airflow levels, and a restrictive intake and exhaust system will further limit it.

A clutch-type LSD can be rebuilt.

 

I have it set up at 7 psi or and it drops to 5psi a5 5k rpm but only in 3rd gear an on.

Where can I get a rebuild kit for my LSD?....I'm sorry I'm asking such noon questions I am fairly new to the scene.

Thanks for the reply.

 

By noon I meant noob

 

That sounds normal for a stock car.

The higher gears will produce more load, which will lead to higher backpressures. This will restrict exhaust flow, and reduce turbine/compressor speed. In other words, boost pressure will drop off. A free-flowing intake and exhaust will help, but you may start to have boost creep problems. If stock, you'll hit fuel cut at 8.6 psi to prevent engine damage. Porting the wastegate will help eliminate creep problems.


LSD parts: http://www.mazdatrix.com/G8LSD.HTM

 

Thank you so much. I actually have a 3 inch full exhaust all the way from the turbo to the y pipe and then in two 2 mufflers (no idea what they are).

I'll look in the stickys to free up my intake(I already have a filter) and most importantly how to port the westgate.