What's the reasons for building a Chevy 377?

[JRG53]

Torque? This may be a stupid question. If I'm not mistaken, to make a 383 stroker, you take a 350 block and use a 400 crank, and a lot of machine work. But for a 377, you destroke a 400, using a 350 crank. Just curious why you would want to destroke a 400. What advantage would you get with a 377, that a 400 couldn't give you?

 

[LSCustoms]

Torque? This may be a stupid question. If I'm not mistaken, to make a 383 stroker, you take a 350 block and use a 400 crank, and a lot of machine work. But for a 377, you destroke a 400, using a 350 crank. Just curious why you would want to destroke a 400. What advantage would you get with a 377, that a 400 couldn't give you?

377 high revving motor, good to use on circle track and very reliable up there in the higher rpm range...

 

[-83MONTESS-]

Isnt a 350 block with a 400 cranks also a 377? Without the .030 overbore of course.

 

[khan0165]

a 350 with a 400 crank = 383
a 400 with a 350 crank = 377

both assuming 0.030 overbore
377 = pie x radius 2.0775in squared x 3.48in stroke x 8
383 = pie x radius 2.0150in squared x 3.75in stroke x 8

one more question... the 350's crank main journal size is smaller than a 400's, so how is this small journal crank used in a large journal block?

 

[RITTER]

Isnt a 350 block with a 400 cranks also a 377? Without the .030 overbore of course.

Correct. It can be made a couple of different ways, as you can imagine from the talk of using the 400ci block.

 

[565bbchevy]

Well I know they sell 3.48 aftermarket cranks (Eagle, etc.) with 400 journals and I've heard of bearing spacers to use an actual 350 crank but not sure if I would trust a bearing spacer? If I was going to spend the money on an aftermarket crank I think I would build a 434 out of my 400 instead.

 

[drogg1]

Yes, if you do the math, a standard 4.00in bore 350 with a 3.750in stroke crank would be ~377cu.in. As to khan's question, aftermarket cranks already have the right size journals and are internally balanced most of the time if they are intended for a 383. If you were to want/need to use a stock 400 crank, you would have to machine down the main journals to whatever the 350 blocks require. I can't remember off the top of my head what size they are.

Edit: Woops misread khan's question