Three questions on '90 Spirit Turbo

[Cass]

My 1990 Turbo Spirit ES (bought new) has 135,000+ miles on it and still runs strong. I have always used Mobil 1 with 5,000 mile changes (+ filter) and have driven the car gently. I have had absolutely no problems other than a worn-out driver's side window motor and vacuum hoses starting to crack from age recently (have replaced most of them). It's an incredible car.

My first question is, how many miles can I expect from the turbo? I've heard that I've been lucky to get 100,000 miles out of it and now I'm on borrowed time.

Also, I've heard that turbo 2.5's use different exhaust valves than non-turbos due to higher combustion chamber temperatures. The local head shop (good reputation) reports that this isn't true, and that they have had no problems using the same exhaust valves in turbos and non-turbos alike. Would appreciate some authoritative info on this.

Also, if the turbo blows on a high-mileage engine like mine, should the head be rebuilt if a new or reman turbo is installed, even if compression is up to spec? I've heard that using a new turbo with an old head may cause valve problems. Any advice would be appreciated.

[bfarroo]

With proper maintenance the turbo should last for a long time. If it's had mobil 1 all it's life I'd bet you could easily get 200,000 miles especially if you've been running stock boost pressure all this time. The biggest thing that kills turbos is to shut them off hot. This burns the oil that is in the turbo and plugs up oil flow especially if conventional oil is used. So if the car has always been idled down properly after spirited dirving everything should be fine. These cars get their bad reputation from people that go out and beat the crap out of them, don't perform proper maintenance and just plain don't take care of the car. Then complain when something breaks. Any car treated this way is going to have problems. Keep with the Mobil 1 and you should be fine.

Later

Benji