Intake manifold fitment


Senior citizen
Aug 13, 2005
I am in the process of swapping manifolds & using felpro 1200 intake gaskets. The manifold won't sit down enough to start the bolts on both sides. The block has been decked .010 & the heads have been shaved .010. I had the manifold shaved .020 on both sides yesterday & it still won't fit. Anyone run into this?

Are you trying to mount it using the FelPro gasket? If so you may have to use the stock metal GM type, which is thinner.
I think most guys use the FelPro MS96033pb which is the valley pan gasket. I have Champion ported iron, and it fits perfectly around the ports.
Milled just the sides? You also need the ends milled. I also run the MS 96033pb on Champion ported irons and like Chris G. matches up perfect.