Weird revving without moving problem...?

[AL92]

If I drive my car at low boost it seems to be ok I leave the lights normally and it seems to accelerate normally.If I take th revs way higher and up the boost a bit to say 15 from the 10 its at right now the car freerevs and goes way up there fast and the car dont' move out at all just sits there.I doubt its wheel spin on dry pavement.I do have a 50 trim and am still on stock clutch.My new act is not in yet.I tried to do a high gear test for slipping clutch and it doesn't seem to me to act like a slipping clutch should in fifth.Arent the revs supposedl to increase fast in fifth when you floor it? I have heard a couple other ideas something about a drivers side axle not in right due to lost c clip or something or toasted viscous coupling maybe.What are the symptoms of a viscous coupling failure?
Is that c clip front drivers axle coming out pretty common thing?
Is it possible for my clutch to only slip at higher boost when revved real high and not to slip in fifth gear?

I get terrible 60fts when it does this slipping thing like 2.9!! I have a unit that can measure them.Also right now my best 60ft is a pathetic 2.24 so pretty sure something is really wrong there.

I don't seem to smell clutch all that bad though when it does the slipping thing either.The car seems to drive normally other than that.

And if viscous coupling is gone how much are they new and used approximately?

 

[Sean485]

The "put it in high gear and get on it and see if it slips thing" is good, but on a turbo car it might not slip because your way out of the powerband. It sounds like a dead clutch to me, if it was a bad VC it would seem like the clutch was slipping all the time, not just when you get on it.

 

[PokinatchaPunk]

I concur with the prior poster's thoughts on it....I had the same thing happen as my clutch was going out. If you start to notice it in other gears besides 5th that should verify it. I'd throw a new clutch in there anyways....If it's not the clutch now it will be soon with that 50trim on there.