Basic Question about Blocks

[Blownpiston]

Are all corvette 350 blocks, 4 bolt mains, or was a 2 bolt main cap ever offered? I have what i was told is a corvette block. Im not so sure anymore, till i run the numbers. Also, can a fairly reliable 383 stroker, be made out of a 2 bolt main block. Or does the sheer torque involved say, feed me a 4 bolt morris! Thanks to any and all that knows.

[MrPbody]

The majority of early 350s were 4-bolts. The 2-bolt block was used extensively during the mid '70s. It's very possible a 2-bolt was used as a matter of convenience.

The 383 really should have 4-bolt mains. If you keep the revs under 5,500, and power under 400 HP, it should be okay.

Jim

[Blownpiston]

MrPbody, Thanks for info. Ill just go up to 400 hp. then, and call it good. Cant see mahine cost involved to add 4 bolt caps. Ran my number # 14010207 Malibu, Camaro, or Light Duty truck motor. I have the 2 bolt version. Darn, hate that. Thank you for clearing up my ignorance. But, i really wanted to build a stroker. Maybe next time.

[MrPbody]

BP,

All is not lost. 4-bolt blocks aren't rare or expensive. If you REALLY want the high powered 383, just get a 4-bolt block and build that. Average price for a standard bore (will "clean" at .030") is around $150-$200. If you have trouble locating one locally, e-mail me and maybe I can scare one up.

Jim

[Blownpiston]

MrPbody, Yes, now my hunt is on for a 4 bolt main block. Thanks for the offer, to help locate a block. I just might take ya up on that, but we both know shipping would probably kill that. You are right, if i dont go ahead and do a 383 stroker, ill always wish i had, and therefore be never really happy. Thank you for all your support, and knowledge shown.

[MrPbody]

BP,

Where are you? I know some folks on the Left Coast, too.

Jim

[Blownpiston]

MrPbody, I am in Shelbyville, Indiana. Not far from Indy. I love that "left coast' note! Everytime i call a salvage yard for a block, its oh i wish we had some too. So, where are all these blocks to be had. Am i missing a mother lode dealer, or hoarder with 80 of them in his attic somewhere? I will find one. I will build this engine. Congrats on being a certified machineist. Not everyone can do that type of work. You are respected for your talent. Thank you, as always.

[MrPbody]

BP,

Your best bet to find one is the local "advertiser" paper with classifieds. You MUST actually pull the pan and LOOK at the mains to be certain if it's a 4-bolt. Casting numbers may or may not tell you what you need to know.

It is accepted that the earlier ('69-'74) are the "hardest" material, but I have no scientific data to back that up. You want the "driver's side dipstick" version. If you find one, get a "money back if it's cracked or .060" over" deal. It must be usable for you to pay out cash... Duh... A "large journal" 327 block or a 302 block (RARE ANIMAL, "DZ" code) are functionally the same as the 350 block. I don't know that I've ever seen a large journal 327 with 4-bolt mains, but that doesn't mean thare aren't any.

There should be plenty around. Good luck!

Jim

[Blue Bowtie]

Actually, if you want a BETTER final assembly than a factory 4-bolt, start with a 2-bolt casting, purchase aftermarket splayed 4-bolt caps, and machine for those. Factory 4-bolts aren't really the best for ultimate strength. Bypass the factory truck blocks and build a stronger crank/main web area.

However, if you really crave a factory 4-bolt, I probably have a fresh/ready spare or two lying around in trash bags.

[MrPbody]

Blue Bowtie,

What you say about splayed-mains is certainly true. However, for a build at this "level", hardly necessary. The cost to install splayed caps is around $600 (caps and machine work). A rebuildable 4-bolt is in the $150-200 range.

For a race engine, I whole-heartedly agree. We've done a few here.

Jim