Recently I installed a new intake gasket set, 89 TPI 5.7. Originally 5yrs ago the gasket went at the front water port sending coolant into the lifter valley. Replaced the gaskets and after a yr or so it developed a miss. Found 2 cyls on pass side oil fouled. I finally got around to replacing it again and found the intake slightly warped. My friend used a machineists stone and hand ground the manifold and trued it up. I reinstalled it and this time used the old type Permatex, torqued in sequence and to spec. Questions is this, I was told by my friends at a Chevy dealer that once it goes out it's done, that is it is more likely to warp again. I am probably going to a new intake, GM wants about $950 my cost or in the alternative I am looking at the Edelbrock baseplate/runner kit. Ant thoughts as to quality of aftermarket vs OE or is there something better out there. Second, I was told by a friend who is a tech rep for a domestic car company to never ever use a sealer. He claims that the factory gaskets must "slide around" as he called it. I used the Fel-Pro kit this last time, the one that comes with everything for the top end. He recommends the OE gaskets over the aftermarket. I read on the Edelbrock site not to use thier "blue" gaskets, but the ones in the kit were blue. Edelbrock says the blue ones are too hard. They even now give the GM part # as well as a couple of others. Need some expert advice, I go back to the days of cast iron to cast iron. Looking at the way aluminum moves around I want to do it correctly. TNX, Danno

 

The gaskets shouldent slide at all thats how they get ripped and eventually blow out. I wouldent use sealer (RTV) unless it was on a known warped surface even then I might not use the warped part at all. OE gaslets are fine but many aftermarket gaskets are a tad thicker to seal imperfect sufaces. I persoanlly like cheap o engine seal gaskets as far as intake gaskets go. They come with a rubberized coating to aid sealing.

 

i'd get rid of the warped intake. Once the integrety of metal is messed up, it;s never as strong. Words of wisdom from my grandfather.....

 

a warped aftermarket intake is usually fine... just machine it flat and it will seal again for another 15 years.

the OE ones usually have thinner castings, but as far as TPI bases and L03 intakes go (i donno about other OE thirdgen ones) you can machine thoes flat again and be fine for another 10-15 years of service too....


EYEROCK89- metal warps for various reasons.. in this case, usually heat cycling... but its not any weaker.....


as for gaskets i usually use Felpro.... ive never had a intake that ive replaced leak.