Hey all, thinking about doing my intake manifold leak and I was talking to a friend, and he said there was a gasket for the LT1 that not went over the side banks, but ALSO goes over the base where the intake rests. Anyone hear of this? And if so, who has used it.

 

Never heard of a gasket like that, don't think it exists. I got another set of OE gaskets and used Ultra Copper RTV for what wasn't covered by gaskets. That Project Trans Am guide is good.

 

as far as i know, it doesnt exist, rtv the middle.

 

If it did it would be nice....use RTV for the time being and let it sit for atleast 24hrs!

 

yes thats the key letting it sit overnight before starting it up, i wish there was a gasket for the front and side rails but a good bead of rtv copper will do fine

 

A good friend of my dad's told me that they do make seals where the rtv goes, but they are crap because they just slide out under pressure. He said he built a motor for a guy that insisted on that seal and not rtv. He had his IM pulled three months later.

 

Thanks all, looks like i will be tackling this project this weekend :-)

 

There is alot of expansion and contraction with heat on these manifolds. The RTV does a much better job of sealing something like this. I would use the Permatex 5200 if you can find it. This stuff is the shiz. I would take it over any copper stuff. It's just a pain to get off but you know it works when your trying to get the part off!

 

They tried all kinds of ways to make the rubber seals stay on the old SBC engines. They most always squished out. Then RTV came along and made the rubber gaskets obsolete. The RTV is actually better.