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· PrOpeller
705 Posts
Discussion Starter · #1 ·
In order to fit my dual sidedraft manifolds, I ground away the webbing between runners on a spare sprint manifold I had. I used a dremel-type device with cutoff wheels to cut the webs out first. Then I went back and ground the flash smooth. I left 1/2" - 1" of the webbing running along the tubes for aesthetic and structural reasons. Then I painted it with Griot's 1400 degree cast iron manifold paint and inserted mounting studs on the bottom.

It looks great. Unfortunately, it won't bolt up to my cylinder head! It must be warped. This was an old manifold, and I didn't check beforehand (stupid me!). Could I have caused it to warp by grinding away the webbing???

I still have the original sprint manifold that was attached to this engine. Should I even attempt to grind away the webs again???

I can't access the bolts under my manifolds without removing part of the webbing... which means a header would now be required.

I have to install these webers and my new roller rocker arms before the Alpine 500 in two weeks. Not to mention the Silverstate Classic in one month.


· Super Moderator
15,246 Posts
It was probably warped before you cut the webs. They usually warp from loose bolts in a previous life...

It can be machined flat assuming it's not too warped. If the flange thickness is reduced by too much, the intake flange may not line up under the heads of the bolts. They should be 12mm thick (.472").

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