GrtWht91

I have a 91 vette, nothing changed internal, just superram and bolt ons as in headers, msd ignition, 58 mm tb, etc, i have true duals on the car, well on the right side the car is smoking what im about positive to be oil, the left side is fine, im thinking the best place to start is a compression check, oh and the car just hit 100,000 miles, any advice would help, thanks

RRT vette

I would do a compression check as well and check the plugs. What color smoke?

GrtWht91

bluish, im hoping that it could be the valve seals instead of the rings going....

Pete K

If the lower base manifold was changed, the intake gasket may be leaking and drawing oil from the lifter valley.

GrtWht91

so the best route to go is to check the compression to rule out the rings then it could be the intake gasket or the valve seals?

Pete K

If you can borrow a leakdown tester, it would give more definative results than a compression tester.

GrtWht91

alright, that sounds like its the priority on the list, thanks for the advice and help

Vito.A

Petes right. A leakdown test on each cylinder at TDC is the best method to diagnose it. You will need a regulated 90-100psi air source for the leakdown tester.
When you do it, listen down the throttle body (for intake valve leaking), then down the exhaust to see if the exhaust valve is leaking, and also through the oil filler cap (leaking around the rings).
Start with #1 and work your way through the firing order.
Record all your reading for future reference.

If all the cylinders are good, then he is also right about checking the intake gasket. They are notorius for slipping down slightly and allowing oil into the intake port and it is usually on just one side.