My 92' Z28 5.7 Intake manifold is leaking at the front drivers side where it bolts to the heads. I had the gaskets changed and sealed with "the right stuff" around ten years and 20,000 miles ago. Searched the threads and didn't find one that fit.

The question is, is there an aftermarket intake manifold base that seals better on the 5.7's? Everything else on the car is stock and I have 74,000 miles on it.

 

I'm guessing that coolant is leaking. Did you retorque the intake after you heat cycled it a bit?
If the intake isnt corroded, the gaskets do wear out need to be replaced every so often.

 

Yes TTOP, at this point there is a hissing from this area when there is water on this location, which lasts for quite awhile after the car is turned off. The intake was not retorqued, I had the work done by PRO DYNO in Tempe AZ and they said that it would never leak again with the sealant they used. Living in Cali now. The torx heads look impossible to reach without removing some items. Is there a low head torx wrench available for this? Worth trying tightening before having the gaskets replaced again.

 

if you have gone to the point of removing the runners you might as well replace the intake manifold gasket and check for severe warping or pitting corrosion on the manifold surface. I always put a dab of rtv around the water ports and teflon pipe sealer on the inner 4 bolts even with felpro gaskets.

 

You can try and retorque it but my guess is it will have to be removed and replaced.
I put teflon on all the intake 2 head bolt threads if they are open on to the oil inside the motor.
I also use the teflon paste on the backside of the intake gaskets around the waterjacket openings.
I use fel-pro 120? series gaskets..

 

If it is all pitted around the coolant ports I have a nos 89-92 tpi manifold waiting for someone restoration.