383 block

i went and bought a block im going to go have her cleaned up etc etc.

what do i need to clearance and how much and where?

is there a write up some where


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There's probably a hundred or so 383 clearancing threads, you can do a search for those but you are mainly looking for rod bolt clearance in the block and clearance for the cam. Theres usually not a lot of grinding to be done and you may have to use a small base circle cam. Do a lot of research before you start putting things together so you don't have a costly mistake.

can you see the notches right by the oil pan rails on both side?

My 383 didn't need any clearancing on the block, only on two of the connecting rods so they didn't hit the cam. I think it is a little different for each motor. Check out the pictures here: http://www.nastyz28.com/forum/showt...ght=stroker+101

EDIT: these are someone else's pictures not mine.

correct me if im wrong but how in the hell can a rod hit the cam

The longer rod puts it closer to the cam especially if you have a high lift. not an uncommon problem with strokers.

To clarify if you look "up" into the motor you will see that the bottom of the cam is "open" and as the con rod moves by it it sometimes hits, it shouldn't hit on the base circle of the cam but if the lift is enough you may have clearance issues.

Also note:
Many H-beam con rods are "profiled" for more cam clearance to help in that area. If look at one from the side I think you will see what I am talking about.

Of course, the small base circle cams can help, too.

I did my 406 (same stroke as a 383), and had to clearence the block a little, but I had a small base circle cam and profiled H-beam rods so no problem there.

i used a standard base circle cam (1.100 inches ) because i already had it before i built my 383.and my H beam rods cleared just fine. but it wouldn't be a bad idea to go with a small base circle cam. you'll just need longer pushrods.

Assemble and the you or your machinist check clearances.

383 with SIR 5.7 rods with cap screws had no problems clearince CC XE274 cam with std. base circle. A couple of cylinders need help at th bottom of the bores (3.75 stroke). Oil pan side rails needed clearancing.

You or machinist HAS to check everything before starting the engine.

Also check clearance between the pin end balance pad on the rod and the underside of the piston. Of course, this should be checked on every build, I'm just throwing it in while we're talking checkin' clearances. I keep a wrist pin on the shelf for this operation that I sanded down to a slightly smaller diameter so that it will just slide through the piston and rod.