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Old 08-28-2010, 08:25 PM
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ericnova72 ericnova72 is offline
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The 5.7" rod is a bit taller at the bolt head than a stock 400 5.565" rod is, with a longer bolt, and frequently has the problem you describe. If the edge of the rod near the bolt head and the edge of the bolt head won't clear the cam you have you can grind it for clearance, cutting that edge of the rod away along with a slight amount from the bolt head. If this has been done and you still don't have enough clearance you then have two choices.

One is to use stroker clearanced capscew bolt type rods that use a capscrew instead of a bolt and nut, the body of the rod is threaded for the bolt(Scat, Eagle, etc I-beam or H-beam), since there is no bolt head in the way on these types they can be clearanced farther.

The other option is the reduced base circle camshaft, which basically means the whole lobe is just proportioned smaller. The heel(or no lift portion) of the lobe is ground on a smaller radius, allowing the whole lobe to be smaller but still provide the same lift and duration profile. this makes the lobe clear the rod bolt head area of the rod. Many common cam grinds are available as a reduced base circle already on the shelf, some others need to be custom ground, but every cam manufacturer offers them, you just have to know enough to ask for one. They are available in every cam type, flat tappet, hydro roller, and solid roller

If you search "383 stroker" builds here I'm sure you will find plenty of pictures, this question comes up fairly often. Info will be the same for you because you are working with the same 3.75" stroke crank into an SBC using 5.7" rods.
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