Technical Pulled this crank out of a 283, but casting # doesn't compute!

Benno,
Only trouble with doing it that way would be finding 283 composition head gaskets. I know 4.00 bore head gaskets would work, but I kind of like using a gasket that's a little closer to the actual bore of the engine. The last time I tried to find 283 head gaskets (long time ago) he only ones I could find were steel shim gaskets. So if you use them (.020) compressed thickness, you'd need to leave the piston .020 in the hole, to get your .040 clearance.

I ran the extra .020 through a compression calculator and it came out to .40 compression difference. But the quench is something else entirely.

You gonna run the original heads on the engine?

 

Another point about the head gaskets. Finding ANY kind of small bore, direct-fit-to-bore-size, is almost impossible, steel shim, composition, or the "new" MLS. There is ONE company making the correct bore head gaskets, SCEgaskets.Com (and they're .015 steel shim!!!!!). Here's where E-Bay comes in again, but you'll most likely have to bid against others wanting the same; most likely Stock or Super Stock racers. I recently bought 2 pairs of NOS 283 gaskets for my future projects, and I got them CHEAP! I've bought some steel shim 305 head gaskets, and some meant for marine applications also. There just is't the need for the 265-283-327 stuff like there was 30-40 years ago. You have to accept some compromises, such as "universal" fit head gaskets (4.125 or MORE on a 283???), unless you're very diligent. I am Butch/56sedandelivery.

 

No sir, 601's. But I do have the heads it came with, they have the single "^" on the end of the head. Would it be better to use the original heads with the 3.960 bore, .015 thick steel gaskets or could I use them on the 601's? Better to just get the 4.00 bore with the 601's and be done with it? Fascinating stuff.

 

It is really hard to build any compression with these small bore, short stroke, SBC engines. Stick with the 601's; they'll have hardened seats, maybe you got lucky, and they have the 1.84 intake valves as opposed to the 1.72 most of them have. The Power Packs also have 1.72 intakes. Someone could have installed larger valves in any of them however. Buy the .015, steel shim, head gaskets from SCE; don't use the universal style at all. A composition head gasket, and pistons being down a ways in the cylinder, will give you more quench than you should shoot for. The SCE gaskets are cheap enough at $60.00 a pair. The shape of the chambers on the 601's will be fine with the head gaskets. If you don't deck the block, and use the .020 down-in-the-hole pistons, your quench is going to be .035, just a bit tight, but I think you'll be OK with that. Usually, most target to get .040 to .045 quench. .035 is a lot better than say .060 however. Being down-in-the-hole .020 will give you a little more la***ude in regards to valve lift also. I am Butch/56sedandelivery.

 

Danger of valve interference or pre-combustion with .035?

 

FWIW in Studebaker's later days they were buying engines from Chevy.
According to this, in the mid-late 60s the Chevy 283 V8s were at first supplied with forged cranks had no dampers, just solid hubs for the pulleys/sheaves, etc.
Then a change was made to cast cranks, with dampers.

 

I think you'll be OK with a .035 quench, but a lot of guys say stock pistons are actually .025 in the hole, so that would make for a .040 quench, even better. The original, early year, 265/283 pistons had NO valve reliefs, so any piston with them has that advantage of more clearance with the valve/piston; the change to factory supplied valve relief SBC pistons came in later 57/early 58. I am Butch/56sedandelivery.