i just bought a 93 tt in florida and drove it back to ohio. it has a boost gauge and aftermarket exhaust from the downpipe all the way back. it has 80,000 miles. there is a problem, it is not nearly as fast as it should be. when i get on it the boost gauge goes to between 7-10 and i hear a huge woosh of air and i can hear the turbos working but it is about half as fast as it should be. what could be the problem? i noticed there is a hose(intake hose?) it is right in front on top about 3 inches in diameter and 3-4 inches in length with a clamp holding it on between two metal pipes. it definitely needs replaced.(some cracks that are letting in air)could this be some of my problem? also when i started it up this morning, tons of black smoke came out of exhaust, is that really bad? forgive my ignorance about this stuff, i'm learning. thanks for any feedback. also what should oil pressure read on the gauge?

 

I seems your describing the turbo intercooler hose. If they're ripped or cracked you'll definitely be losing power as the output from the turbos are leaking out. One other common hose failure point is the one connecting the black flattish pipe toward the rear of the engine. the wooshing sound is definitely boost air rushing out. Normal boost pattern is 10psi to 4500rpm, quick dip to about 8psi when the transition to second turbo takes place then back up to 10psi, should hold to redline.

 

is that turbo intercooler hose a specialty part from the dealer or can i make my own from some rubber hose? if not the dealer where would i come across something like this?

 

I don't think you could make your own, because the system needs to be able to withstand 10+psi of boost pressure. Not sure what kind of aftermarket stuff is available, as far as turbo plumbing goes.

Check all of your large hose connections. When I bought my car, the black flattish pipe that Sidestick mentioned was not tight and had blown loose. Once I reconnected it, power increased DRAMATICALLY! Since you're hearing a big whoosh of air, its definitely a boost leak.

Paul

 

The rx7store has some pretty cool intercooler piping. I think it's fairly priced for being polished. Check it out. If anyone knows about any piping for the intake, I would like to know. Thanks.