350 4 bolt block?
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Burning Brakes
Joined: Nov 2000
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From: BowlingGreen KY
350 4 bolt block?
I've found a 350 4 bolt block I want to use for a 383 build up. The cast number is 3970010, I think its out of a 1969 Z28. Will my stock 1990 L98 heads and intake work on this block? Thanks in advance. :cheers:
Race Director
Joined: Oct 2001
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From: Fear causes hesitaiton...and hesitation will cause your worst fears to come true. Houston TX
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Cruise-In VII Veteran
Re: 350 4 bolt block? (KYVette90)
Sorry I don't have the answer, but I am curious to know as well. At least this will get this ttt. :seeya
Burning Brakes
Joined: Dec 2000
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From: Marietta, South Carolina, USA
Re: 350 4 bolt block? (KYVette90)
The block will work but I dont think it came out off a Z28 because they came with 302 if I remamber right.
The only thing you have to worrie about is that this block is made for 2 piece crank so you will have to get a 2 piece crank and not a 1 piece like you have in your car now so you will have to change the flexplate.
Jay
The only thing you have to worrie about is that this block is made for 2 piece crank so you will have to get a 2 piece crank and not a 1 piece like you have in your car now so you will have to change the flexplate.
Jay
Burning Brakes
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Re: 350 4 bolt block? (MrJay)
The block will work but I dont think it came out off a Z28 because they came with 302 if I remamber right.
The 3970010 block was used from '68-'76 and came both as 2 and 4 bolt. I have a '69 #3970010 2 bolt block (never rebuilt).
Burning Brakes
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Re: 350 4 bolt block? (BBA)
Hey Rick...that block was even used as late as 1995, in trucks and vans. I have a fresh .030 over 010 block from a 1993 panel van in my garage right now.
Safety Car
Joined: Dec 2000
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From: Jacksonville Fl
Re: 350 4 bolt block? (Rick86)
The 68-76 was what was printed in my Chevy SB Interchange Manual copy right 1989
In short, that is the worlds most popular 4 bolt main SBC made, GM used it in EVERYTHING listed as high performance or heavy duty.
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Safety Car
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From: Atlantis
Cruise-In I Veteran
Re: 350 4 bolt block? (BBA)
The 69 Z-28 DID have a 302 CID engine.
BUT . . .the block was a standard 4 inch bore 4 bolt main GM small block.
The CRANKSHAFT was 3.25 inch stroke if memory serves me correctly.
(don't make me swear to this as the 327 CID is in there somewhere)
but the stroke was same as a 283.
It was a LARGE journal crank whereas the atandard 283 crank was the SMALL journal shaft.
I have one, original block and crankshaft with a set of the old 202 heads on it.
You CAN used the block to build yourself a 350 or a 383 stroker or whatever you want.
You "might" want to check and see what that block is worth to some of the old Camaro/Z-28 purist before you use it.
350 4 bolt blocks aren't hard to come by but there are few of the original 302 blocks left after 30 some-odd years.
BUT . . .the block was a standard 4 inch bore 4 bolt main GM small block.
The CRANKSHAFT was 3.25 inch stroke if memory serves me correctly.
(don't make me swear to this as the 327 CID is in there somewhere)
but the stroke was same as a 283.
It was a LARGE journal crank whereas the atandard 283 crank was the SMALL journal shaft.
I have one, original block and crankshaft with a set of the old 202 heads on it.
You CAN used the block to build yourself a 350 or a 383 stroker or whatever you want.
You "might" want to check and see what that block is worth to some of the old Camaro/Z-28 purist before you use it.
350 4 bolt blocks aren't hard to come by but there are few of the original 302 blocks left after 30 some-odd years.
Instructor
Joined: Nov 2001
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From: Houston Texas
Re: 350 4 bolt block? (VetNutJim)
Not to get really pissy but the 302 was 4 in bore by 3 in stroke. Any other combo was not a 302. 327 and 350 both shared the 4 inch bore. Can't remember the exact stroke on a 327 but I think it is the 3.25 in stroke crank, while the 350 is a 3.48 in stroke.
Safety Car
Joined: Dec 2000
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From: Jacksonville Fl
Re: 350 4 bolt block? (VetNutJim)
Except the 302 block was a 2 bolt main block with the same casting number as the 4 bolt block. ( I do not think it was 3970010, I can't recall the actual number off the top of my head ).