Thread: Making 350 rods fit on a 400 crank

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What grinding is required and where on stock 350 rods to make them clear on a 400 crank in a 350 motor ?
I know I have to have the 400 crank main jurnals turned to 350 size , are there any block clearances to worry about ?

Usually, but not always, you'll have to grind the rods at the bolt head for cam lobe clearance (0.080") and grind the block a little at the pan rail. Cam/rod interference can also be handled by using a reduced base circle cam or by using 400 rods.

Mine also had to have the block clearenced on the base of 4 of the cylinder bores along with the pan rail and the rod bolts at the cam

Ron, There is a lot of variations in Chevy blocks. Some have to be clearanced all over and some act like you have an aftermarket block made for stroking. Check with your machine shop because sometimes they will clearance a block for around 50.00 extra when they are doing your other machine work. That works out real well because if you get your machine work finished and then start mocking up for clearancing you take chances of stratching your pretty hone job and not to mention all the shavings that get in the block from clearancing. At the machine shop they do a final washing after everything is done and when you bring it home its ready to put together. BUT NEVER EVER TRUST THAT, ALWAYS CHECK YOUR CLEARANCES ON CYLINDERS AND CAM AND PAN RAILS AND EVERYTHING.

One other point is you mentioned turning a 400 crank down. That's a bad move because it will cost more to do it with the right fillet than a brand new and better Eagle crank will cost. Go with a Eagle or Scat crank. They're both good in my experience with them.

I am also building a 383 with 5.7 rods. Does every rod have to be ground for cam clearance?

Originally posted by deuce4papa
I am also building a 383 with 5.7 rods. Does every rod have to be ground for cam clearance?

THE BEST WAY I HAVE FOUND TO DO THIS IS.INSTALL THE CRANK,THE CAM THEN THE TIMING CHAIN.FIGURE OUT YOUR PISTON PLACEMENT.USE LAY OUT DIE OR BRIGHT BLUE PAINT SPRAYED ON THE ROD BOLTS AND THEN INSTALL ONE PISTON (WITH-OUT THE RINGS ON IT) ON THE CRANK. DON'T FORGET TO PUT YOUR BEARINGS IN THEN ROTATE THE ENGINE SLOWLY MAKING SURE THAT ROD OR ROD BOLTS DON'T TOUCH THE CAM OR BLOCK ANYWHERE.IF IT DOES REMOVE AND LOOK AT THE BOLT OR ROD AND SEE WHERE THE (NICK) IS AT REMOVE A SMALL AMOUT OF MATERIAL WHERE IT IS TOUCHING AT AND TRY IT AGAIN.IF YOU DON'T LIKE TO GRIND YOU CAN ALWAYS USE A SMALL BASE CIRCLE CAM BUT I WOULD STILL CHECK IT DUE TO (CORE-SHIFT ETC.).