Can you please tell me what modifications are required to convert a 302 Boss intake to fit the 351 Cleveland. Thank You
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I've never done this, nor have I heard of it. Basically, the 302 intake is about 1-1/2" too narrow. So to use it on a 351C, you'll somehow have to carefully measure the exact gap you have, then fabricate thick 'filler' pieces of aluminum or phenolic plastic to fit between the heads and intake, with a gasket glued on each side of each spacer. The ports in the spacers should be cut to match the heads and the intake, but you can disregard the water passages. 2)- The 302 intake is 'wet' meaning it normally runs water through it with a thermostat under the outlet elbow. You get to unbolt or cut away all this 9depending on which intake you own) since the 351C uses a dry intake with the thermostat in the block. Besides, this stuff is about where the 351C distributor will be sitting. Finally, the front & rear edges of the 302 intake may need trimming or extending to fit around the distributor, and to seal the remains of the intake to the end-dams of the 351C block. It seems like a LOT of work, done only by poor but skillful fabricators. I'm not certain if its possible to make any of the intake bolts line up with the heads; new boltholes may need to be drilled & tapped to hold the assembly together, or some tricky design work with the port spacers might let extra bolts work. a TIG-welder may be needed.
I've made a number of intake adapters but never tried this one. You may be able to make adapter plates to fill the gaps but you wont get the vertical intake bolts to match the correspond holes on the heads no matter what you do. They may be offset enough that you could drill different holes in the adapter plates. Boss 302s are unique to Cleveland heads on small block deck heights and good for nothing else. If the Boss 302 you have is in decent shape, it will bring $200-300 on e-bay. It won't perform any better than any other good 4V dual plane intake on your cleveland. Sell the Boss intake and buy a Cleveland lid. There'll be two more happy people in the world.-You and the guy that needs a Boss 302 intake.