Whats wrong with my 1990 300zx?

hi, i am new to the forums, i just bought 1990 300zx with 72k on it (km not m). the clutch was slipping when i got it and a few days ago just completely cut out. when i put it into gear and try to drive it just revs. Would that be my clutch that needs to be replaced? or one of the cylinders?

also. my car sometimes shut off when driving (more common after driving harder)

(car has electronic boost controller up to 16psi but only ran at about 6-12 , 2 1/2 inch dual exhaust)

Please help, whats wrong with my z so i can get it back on the road but have a little knowledge so the repair shops dont try to walk all over me!

First things first ,, with 70 k on your car.. When did it have the timing belt replaced if it even was?
Second, if it wasn't or hasn't been replaced .. DO NOT DRIVE IT anymore until the belt is repalced.. Or you'll trash the engine..!:nono:
I've seen the belts snap with 70k on them especially if you have a TT. What's a $30 belt compared to an engine replacement

First things first ,, with 70 k on your car.. When did it have the timing belt replaced if it even was?
Second, if it wasn't or hasn't been replaced .. DO NOT DRIVE IT anymore until the belt is repalced.. Or you'll trash the engine..!:nono:
Dont scare the kid. T belts last 100k(km) or 60k miles

Sounds liek your in safety boost... so run your ecu codes and that will be a big lead.

But for the clutch issue... does your pedal feel normal?
It may be time for a new clutch.

It shuttng off is most like due to a vaccum leak. do a boost leak test to find out. or the ecu might tell you.