I have a 454 engine out of a 1987 GMC 1 ton truck. I need the crank and block at a minimum. Question is, before I tear apart a good running engine for nothing... will it work in my boat?
That is... is it a forged steel crank? Is it a 4 bolt main block? With a little machine work, is it as good a motor as my 88 Gen IV 454 Mag 385 Hp block and crank that I need to replace?

not the same engine,cast crank,3/8 rods small peanut port heads some are 2 bolt and some are 4 bolt mains.my truck had a 4 bolt mains because it was a 4x4 dually and came as a cab and chassis originally

So this truck is a 4X4. You're saying it could be a 4 bolt block, and that would be feasable? But you're sure the crank is cast. That seems odd they would put a cast crank in a 4 bolt block.

I don't care about the rods, pistons or especially the peanut port heads. I only need a block and crank.

The crank will be cast. The block however, even if a 2 bolt main will work just fine for what you're doing.

GM 2 piece forged cranks can be found fairly cheap. For about 200-250 bucks. Nice thing about a car/truck block, esp in a mark iv, where the head bolt holes are exposed to water jackets, is that corroded bolt holes normally isnt a issue.

call bob madera,he probibally has everything you need,and at a fair price.

you say 2 bolt would be fine for what i'm doing? How do you know that? I'm not running completely stock. My components are as follows... 9 1/4 compression, N/A, Roller cam, Dart Pro 1 heads.
I think you're saying as long as it's not blown it will work fine for me?

i know SBC is bifferent from BBC but i more or less took a vortec 350 from a 1997 truck, changed the pistons, intake, and cam, balanaced the crank, outfitted for marine use and spin it to 5300 rpm with a cast iron bottom end

Ice,

I had one in the shop a couple of days ago. It was a 4 bolt main block and had a cast crank (that was in three pieces ) I dont know of any way to tell if the block is 2 or 4 bolt without pulling the pan.

If the block is a 4 bolt it should be fine for your deal. Is your crankshaft that bad that it cannot be reground ?

Hope this helps,

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

4 bolt blocks will have a bigger pipe plug above the oil filter pad

im using auto blocks in my build as well..

i had a 4 bolt main with a cast crank came out of a suburban kinda wierd but they do it..

Here is a link to BB casting numbers, hopefully it will be of help.

http://www.teufert.net/bbchevy/bbcast.htm

Phil