Planning to put together my 5.8L today. Can I just use RTV instead of those cork gaskets? I know on my small block chevy I've just used RTV instead of the goofball end seals and it works absolutely great.

I've always used red rtv, but I was planning on using that "copper" rtv.

On a separate note, I had the heads decked so they're smooth. Any recommendations on using that copper spray on the head gaskets? I know I used to use it on my POS 1.4 liter Datsun 210 that had a terrible water jacket design (very small gap) and used to blow head gaskets.

Thanks in advance.

 

I see no problem in using RTV alone for the end seals of the intake. I do it all the time with no problems at the shop. I have prefer the Perm-A-Tex Ultra Grey and just give it about 10 to 15 minutes to "skin" before setting the intake on. Also make sure that there is no oil on the mating surfaces. As for the copper spray I've never tried it for the 351s

 

& I'm going to go ahead & use the copper spray.

It can't hurt and I want these guys sealed well.

 

True, Let me know how it turns out.

 

Depends on the gap you have, if it's bigger then no way the RTV will get pushed out pretty quickly and you'll have a major oil leak. The best luck I have had is with cork gaskets believe it or not, but I clean the block and glue them down with contact cement first, and then RTV the corners and maybe a little bead across the top to seal against the intake.

 

For the end gaskets on the lower intake manifold. Working like a dream.

I had a heck of a time with the passenger side valve cover. Ended up doing it 3 times. I tried using a cork gasket twice (with right stuff) and the 3rd time I just used "The Right Stuff" w/o a gasket. Sealed beautifully. I don't think I'll ever use a gasket for valve covers again. It's always been a pain for me when the dang gaskets slip.

That passenge side valve cover wouldn't be such a drag except for having to remove and replace that dang upper FI intake manifold.