OBD II exhaust manifold question

[Joe G]

I'm running OBDII exhaust manifolds, and i fabricated plates to cover the air holes. The plates work great, but the exhaust is still leaking from directly above the holes between the manifolds and the block. Do i need new/OBD II manifold gaskets?

thanks

p.s. i already searched extensively, but found no results.

[Philo]

It's leaking from where you say it is, either one of two things is happening. A) The gasket is bad and needs to be replaced (the gaskets are one time torque gaskets, so if it was taken off and re-used at any point I would lean in this direction). B) the surface of either the manifold or head has an imperfection in it which the gasket isn't able to fill.

Either way, they need to come off and you need new gaskets.

[328ijunkie]

You have to use OBD2 gaskets with OBD2 headers

[Joe G]

That's what I figured. I'm willing to bet my car that the moron that started the swap re-used the obdii gaskets.

[herlsy]

I used m50 gaskets with my m52 manifolds, just welded the channels on the back, no issues with leaks.