Clutch help please...

[98fxdwg]

My 89 7mgte (stock engine) is eating clutches, on number 4 in last ten thousand miles, the clutch is made by federated but it is the high performance clutch for lexus' and supras of the era, on a long trip, 80+ miles i can get it to slip at low rpm's, but not when the car is cool. There is no oil or anything leaking into the clutch, or leaking period, so that is not the issue. I don't want to have to go clutch hunting again because I've got some money into the problem already, anbody else with ideas? (master/slave cylinders have already been replaced brand new) Flywheel was turned correctly upon installation...