Casting # for 427/390
Thread Starter
Burning Brakes
Joined: Aug 2001
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From: I can explain it to you, but I can't comprehend it for ya.
Casting # for 427/390
The 454 installed in my 69 is needing a rebuild. I am trying to find a correct 390/427 block to build instead. I know it won't be numbers matching, but I would at least like to have the correct engine in lieu of the 2-bolt 454 that came from a chevelle. If I'm going to have to rebuild anyway now is the time to change.
I have found a 69 427/435 short block with casting # 3935439. would this be the same block used for the 390hp engine or was it a different casting?
I have seen several websites listing the casting numbers but have not found one that identifies hp ratings cooresponding with casting numbers.
I have seen several 427 casting numbers listed for 69 year usage but cannot determine they were for diff. hp ratings or for use in different vechicle applications. I know some are clearly identified for Zl-1 and such, but no help for what I am trying to learn.
any advice??
I have found a 69 427/435 short block with casting # 3935439. would this be the same block used for the 390hp engine or was it a different casting?
I have seen several websites listing the casting numbers but have not found one that identifies hp ratings cooresponding with casting numbers.
I have seen several 427 casting numbers listed for 69 year usage but cannot determine they were for diff. hp ratings or for use in different vechicle applications. I know some are clearly identified for Zl-1 and such, but no help for what I am trying to learn.
any advice??
Drifting
Joined: Feb 1999
Posts: 1,351
Likes: 3
From: Fremont, CA, USA
Re: Casting # for 427/390 (Dwaynes69BB)
Dwayne------
The GM #3935439 cylinder block was, with respect to Corvettes, used for 1968 with L-71 or L-88 AND for ALL early 1969 Corvettes with 427 of any horsepower rating. For 1969 L-36 (390 hp) applications it was fitted with 2 bolt mains; other applications used 4 bolt mains. So, if your car was built before about late December, 1968, the "439" block would be "correct". After that time, the GM #3955270 or 3963512 blocks were used.
The 3963512 was used widely for 454 applications during 1970 and 1971, so that may be the block which you have now. Although not correctly "dated", if you have a 1969 built after about December, 1968, the 3963512 block would be the correct casting number for your car.
A 2 bolt "512" block configured as a 454 cid can be converted to a 4 bolt 427 simply by changing the crankshaft to a 3.76" stroke 427 unit and adding the 4 bolt main caps (machining required to add main cap bolt holes, register the caps in the block and align-hone).
The GM #3935439 cylinder block was, with respect to Corvettes, used for 1968 with L-71 or L-88 AND for ALL early 1969 Corvettes with 427 of any horsepower rating. For 1969 L-36 (390 hp) applications it was fitted with 2 bolt mains; other applications used 4 bolt mains. So, if your car was built before about late December, 1968, the "439" block would be "correct". After that time, the GM #3955270 or 3963512 blocks were used.
The 3963512 was used widely for 454 applications during 1970 and 1971, so that may be the block which you have now. Although not correctly "dated", if you have a 1969 built after about December, 1968, the 3963512 block would be the correct casting number for your car.
A 2 bolt "512" block configured as a 454 cid can be converted to a 4 bolt 427 simply by changing the crankshaft to a 3.76" stroke 427 unit and adding the 4 bolt main caps (machining required to add main cap bolt holes, register the caps in the block and align-hone).
Thread Starter
Burning Brakes
Joined: Aug 2001
Posts: 947
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From: I can explain it to you, but I can't comprehend it for ya.
Re: Casting # for 427/390 (Joe Lucia)
Joe,
My current 454 is casting 3999289 (goin from memory). You have previoulsy helped me to determine from it's pad stamping that it is a 245 hp from a 72' 4-speed Chevelle or Monte-Carlo.
my car is an "early car with the VIN in the low 3000's and a build code of B28 so it looks like the 3935439 casting will work.
Thanx for your valuable input.
anyone need a 454/245hp for chevelle or Monte-carlo??
My current 454 is casting 3999289 (goin from memory). You have previoulsy helped me to determine from it's pad stamping that it is a 245 hp from a 72' 4-speed Chevelle or Monte-Carlo.
my car is an "early car with the VIN in the low 3000's and a build code of B28 so it looks like the 3935439 casting will work.
Thanx for your valuable input.
anyone need a 454/245hp for chevelle or Monte-carlo??
Safety Car
Joined: Aug 1999
Posts: 4,862
Likes: 118
From: Texas
Re: Casting # for 427/390 (Joe Lucia)
Dwayne------
A 2 bolt "512" block configured as a 454 cid can be converted to a 4 bolt 427 simply by changing the crankshaft to a 3.76" stroke 427 unit and adding the 4 bolt main caps (machining required to add main cap bolt holes, register the caps in the block and align-hone).
A 2 bolt "512" block configured as a 454 cid can be converted to a 4 bolt 427 simply by changing the crankshaft to a 3.76" stroke 427 unit and adding the 4 bolt main caps (machining required to add main cap bolt holes, register the caps in the block and align-hone).
Drifting
Joined: Feb 1999
Posts: 1,351
Likes: 3
From: Fremont, CA, USA
Re: Casting # for 427/390 (Cam Potter)
Cam-----
I agree. In describing this in my previous post I am not recommending a change from the 454 configuration to the 427 configuration. I was simply providing information relative to what Dwayne's stated intention was----building a 427/390. And, if one wishes to do so, it can be done using the '512' block. But, I totally agree. Letting the engine remain in the 454 configuration might be the wisest thing to do. As I've stated in the past on many occasions, the old hot rodders' adage that "there is no substitute for cubic inches" remains as true as ever.
If I were going to upgrade this engine, I'd install a forged steel 454 crank, hypereutectic cast pistons, 4 bolt mains (if it makes one sleep better), and LS-6/7 rods.
I agree. In describing this in my previous post I am not recommending a change from the 454 configuration to the 427 configuration. I was simply providing information relative to what Dwayne's stated intention was----building a 427/390. And, if one wishes to do so, it can be done using the '512' block. But, I totally agree. Letting the engine remain in the 454 configuration might be the wisest thing to do. As I've stated in the past on many occasions, the old hot rodders' adage that "there is no substitute for cubic inches" remains as true as ever.
If I were going to upgrade this engine, I'd install a forged steel 454 crank, hypereutectic cast pistons, 4 bolt mains (if it makes one sleep better), and LS-6/7 rods.
