Hey guys, I have a few questions about the 366 tall deck big block 99 model.
1) Can it be bored to a 427 bore?
2) what has to be done to use a regular earlie gm aluminum intake on the motor? do they make spacer plates or something?
3)The heads on the motor are oval port but have Hi-per casted into them under the valve covers. Are these very good heads?
4) are the rods and crank good to use?:o

Cranks are good, the rest of it will make a good boat anchor.

The heads may be okay, what casting number?

There may be intake spacers out there but the tall deck BBCs are funky...you will need a different distributor and pushrods.

And diffenr pistons, I think it is a 4 ring dealio from the factory.

You have much better options. Might have a steel crank though.

Sorry, I forgot to say that it can't be bored to a 427. It would have to have some seriously thick cylinder walls for that and you would spend a grand to accomplish it because each hole would take 4 passes through the boring bar.

Sorry for the third consecutive post, must be getting old or something.

With the tall deck bbc you may run into exhaust header problems too since the heads sit up about half an inch higher than they do on a regular bbc.

The only application I recall using them on is a tube chassis drag car.

Oh yeah, it should have 4 bolt main caps....they are worth about a hundred bucks or so.

Check out the heads, even the worst ones may be used on 500-600 hp applications. But you may spend some coin getting them ready to go.

Crank is a forged 3.766" stroke, same as a 427.
Main caps are 4-bolt, snag 'em for a conversion or ebay fodder.
Rods should be 3/8" bolt "thumb" rods, good pieces.
Block is a boat anchor. Bore is small, heads can't breathe well because chamber hangs so far over onto the deck that airflow is badly shrouded.
One cool thing about 'em, though - you can push a piston completely out the bottom when you tear 'em down.

I've gotta agree with the other guys. Gut the internals, and and scrap the block, or sell the whole thing to someone needing one for their grain or dump truck.

i am in agreement with them--find a 454 stick with the oval ports for the street--best bang for the buck