383 clearance "at home"

we have done a lot of research and asked people who have done it and race them on asphault, dirt, or in a straight 1/4 mile. i see a lot of people here have done it so this is it, the last time i have to look.

350 block 400 crank. install crank, rods and pistons turn crank and mark the block where anything makes contact. probably only use one piston and rod on each side when we do this and just move them from cylinder to cylinder. now remove the crank and rods and gently grind down the contact point 0.060 and be sure to take no more than 0.070 of material off the block. then check again and again for clearance.sounds simple. and if im correct ARP makes a rod bolt that will clear the cam? or i could grind it down as well? would it be better to use the rods out of the 400 or the 350 rods we already have?


this is a low budget "do as much as possible ourselves" build. with some 1.94/1.5 valve heads and a cam not too radical with a swap meet intake and a rebuilt holley 650.


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Might have to grind the contact point more than .060-.070" depending on what block and core shift. What you really need to accomplish is grinding enough away so thar the rod and rod bolt nut clear the block by a minimum .040".

Using the 400 rods is a poor way to do things in todays world, but many strokers were built in the old days using them and it eliminates all the camshaft clearance issues, and is acceptable in a absolute budget engine. Only thing to watch out for is most of the stroker cranks sold today require the 5.7" or longer rod to make the bottom of the pistons clear their bigger counterweights at BDC.

The stock 400 crank won't fit unless you have had the main bearing journals turned down to 350 size, the 400 mains are .200" bigger.

The 5.7" rod is a better build, but you have the clearance issues with the cam. The ARP bolts will help with the clearance but the area of bolt pad on the rod around the outboard edge of the bolt head will need to be ground or filed back, and the rod bolt head itself may need the edge ground depending on the size of the cam. I can't tell you where that point is regarding cam size as I've never built one with a small cam. This is really a very simple issue though, at the most you are going to be removing .040" or so from the edge of the bolt head, and it is a commom practice.

Going to a small base circle cam eliminates the clearance issue but will require longer pushrods.