This should start an argument. I bought a high quality intake gasket set for the intake install. In this kit is inlcuded the two end gaskets to seal the front and back. In the past I have used a bead of silicone in the front and back as the old cork gaskets would blow out. In this new kit the end gaskets have "tags" on them to keep them seated in place. Also, they are very similar to the new one-piece oil pan gaskets in that they are installed dry. Should I use the included end gaskets or a bead of silicone! Also, the gaskets are much thicker than the bead would be and I'm wondering how this would impact port matching on the heads.
On an aluminum intake I use the fel-pro print-o seals. I had the the rubber end seals, which I install dry. I havent had a problem yet. They will want to slip out but as long as you keep an eye on them when you set the intake down you shouldnt have a problem.
On my recent re-cam job, I used BOTH the cork gasket and a bead of Black Silicon. I laid it pretty thick at the four corners. This is supposedly the "problem" area. re: porting job I'd lay the intake down withOUT a gasket, look and SEE if you can tell how the ports match up to the heads compared to having a gasket in place. If the ports line up better without the gaskets, just run a bead of silicon in place of the gasket. I used the Felpro 1262 intake gaskets for my build. Just my
I used the cork end-gaskets along with "gorilla snot" (3M Weatherstrip Adhesive), as my mechanic says it works far better than RTV. I did use RTV on the corners though (where the end-gaskets meet the side gaskets). Now here's a topic for debate: Do you guys use a gasket sealer on the side-gaskets, or install them dry?...
If you read the instructions for the aluminium intake,weiand,Holley, etc. They thell you not to use the cork or rubber end gasket and run a 1/4" bead of RTV. The instructions for Felpro if I remember correctly is to put RTV on the ends of the cork or rubber gaket. I've done it both ways on aluminium intakes with no problems, I think running a 1/4" bead on the ends will give you the best seal and reduce the risk of cracking one of the bolt holes on the end of the manifold (thats probably why the manufacture does not want you to use the end gaskets)
Yes, but I have found that to be B.S. That RTV eventually leaks. If the factory used gaskets, then I use gaskets. I don't believe that RTV should ever replace a gasket. My dad had a '79 Pontiac, and the factory used RTV with no gaskets for the valve covers. Guess what? They leaked after a few years. I installed new gaskets on it for him...
There is a trick chevy guys use to fix the problem. They take a center punch and put a dimple in the block sealing surfuace every 3/8-1/2 inch, then use rtv. It keeps the rtv from sliping out after it hardens. Don't know if it will work the same, but its worth looking into.
Back in 79 GM was using a Blue RTV which we called blue goo and it was crap, chemistry has come along way since then. The problem is today that all RTV's are not the same and you have to make sure you are using the correct one. I don't know the number off hand but you want to use the Black RTV that is oil resitant/high temp, Ford uses this on the 8.8 rear covers and other parts. What you don't want to use is the stuff that has a strong vinegar smell, usally its the Blue, Orange, clear silicon RTV and has acetic acid in it , very corrosive. Its very simalar to what GM used back in 79. I've seen demonstrations from Loctite , Permitex where they put a glob of this stuff in a container with some bolts and screws and after a day or two you have rusty/corroded bolts and screws.
Well, I kept an eye on them after the first torque down and all was good. The second round to full torque resulted in a little slipping on both ends. Not all of the way out but you can see it slipped a little!! I think it will still seal but next time I think I'll go with sealer!! What is nice is the end gaskets worked well for lining up the ports.
