What could be wrong? No signs of oil leaks. He has DP, MP, CB, intake, walbro pump

late

 

Check inside the hose to the IC if its full of oil (drippy wet not just damp-damp is normal) Then it is leaking from the turbo impeller bearing - otherwise may be bad rotor oil seals - Mine currently dump 1qt/380mi into my newly rebuilt engine
if it is not the impeller leaking - & is smoking it may be the turbine bearing leaking into the exhaust - this usually produces large amounts of bluish smoke

 

He could be driving with his foot really into it as well, but 1 qt in 500 miles is pretty close to the limit.

 

If it's an 87-88 he could have a sticking control rod on the oil injection pump.

 

i noticed large amounts of smoke when i get above 5000rpms and let off on the gas or shift, hence letting off on the gas. it eats alot of oil if i'm above 5000 rpms, which of course is almost everytime i'm not in fifth gear.

is this a sign of the turbo bearing seal leaking, my turbo intake is dry as a bone and i've got great compression.

 

Oh, we know what your problem is...

 

Smoke on lifting throttle (High Vacuum) sounds like worn Rotor oil seals.
a leaky turbo will smoke all the time I think

 

i can boost 10-12 psi below 5000 and it won't do it and after it warms up it won't do it until like 6000-7000 rpms.
guess it's time for a rebuild

 

It's not rebuild time yet...just don't abuse the engine and you may have plenty of life left in it.

 

1 qt of oil every 500 miles sounds about right. 1 qt of oil every 380 miles sounds like an oil burner.