I have a 91 305 TPI. The intake is leaking in the back between the block and the intake. I had it off once, and i put in new gaskets and seals along the front and back, and it didnt help. Is it possible my intake is warped or cracked??? How do I tell???? If it is craked or warped, is it repairable??? Or should I get another..... need some help here guys, I am missing my car.... Also, it is leaking in the exact same place as it was before I attempted to fix it. This is what has lead me to believe that it might be a manifold problem. Will a 350 intake fir my car??? and if so what years will fit, 87 and up???

 

Instead of using the front and rear seals, throw those away and put about a 1/4" high bead of black RTV sealant in its place. Make sure to overlap the RTV on the intake gasket about 1/4" on both sides. I always do this and it works great!

It's possible to have a warped intake but doubt that's what it is or else you'd have sealing problems and vacuum leaks. Are you sure it's not a valve cover leaking from the back?

 

I did use RTV silicone along the front and the back. It still leaks, I dont think it is the valve cover, my friend is a mechanic at a Chevy dealership and he brought a dye kit over. He had a little light that showed the dye when it came out and it wasnt the valve cover. I was told if it wasnt torqued down properly, that I could have warped it then......

 

How much RTV did you bead on the back of the block? I usually give it a good 1/4 tall bead and let it tack up fairly good before I lower the intake. Never had a leak doing it that way.

 

I used a constant bead, I allowed it to tack up just a bit before I installed intake...

 

did you friend tell you that? because if it is sealing to the heads the ends will not matter silicone will make up for any "warp" you have in the ends you may have had some oil one one of the surfaces or moved it just right when you put it on the block. you may wan't to check you pcv system I have seen some trucks with messed up pcv systems do similar things.