engine block ID #
Le Mans Master
Joined: Apr 2006
Posts: 5,347
Likes: 36
From: San Clemente CA
Guess it depends on where you get your information...
http://www.montecarloss.com/SSThunder/SBCinfo.html
http://www.nastyz28.com/sbchevy/sblock.php
http://www.montecarloss.com/SSThunder/SBCinfo.html
http://www.nastyz28.com/sbchevy/sblock.php
Racer
Joined: Mar 2008
Posts: 338
Likes: 19
From: Mesa Az
Guess it depends on where you get your information...
http://www.montecarloss.com/SSThunder/SBCinfo.html
http://www.nastyz28.com/sbchevy/sblock.php
http://www.montecarloss.com/SSThunder/SBCinfo.html
http://www.nastyz28.com/sbchevy/sblock.php
The 68 4 inch bore block used on 327 and 302 engines was 3914660 and 3914678. The 69 4 inch block (before the 010 came out) was 3932386 and 3932388 until the 3956618 came out around Jan 69.
Just take one of the multi year listings on your reference for example:
3959532 is shown as a 283 block for 56-67
First, there was no 283 in 56 and the first 283 was the 3731548 casting...do you really believe GM would cast the same block from 56-67 while still casting new ones just about every model year?
The 3959532 and other 39595XX series castings were warranty replacement blocks that were cast for the CE warranty replacement program that began in 68/69. These blocks were needed to service the older models since the small journal engines were no longer used in production.
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Le Mans Master
Joined: Dec 2007
Posts: 8,000
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From: Puget Sound
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,925
From: Washington Michigan
A lot of these references are full of errors and generalizations, probably taken from interchange lists which show what a part could be used for, but not necessarily what it is CORRECT for and were copied from one reference site to another, mainly from MORTEC. You will note things like misread and duplicate casting numbers and ranges of use that span for example,1956 to 1967 for a single casting number which is ridiculous. Very few casting numbers were used for multiple years as there were changes and improvements each year which resulted in a new casting number. The 3970010 casting is one of the few that had such a multiple year application, but it first appeared around april or May, 69 and continued through 75.
The 68 4 inch bore block used on 327 and 302 engines was 3914660 and 3914678. The 69 4 inch block (before the 010 came out) was 3932386 and 3932388 until the 3956618 came out around Jan 69.
The 68 4 inch bore block used on 327 and 302 engines was 3914660 and 3914678. The 69 4 inch block (before the 010 came out) was 3932386 and 3932388 until the 3956618 came out around Jan 69.
Cruising
Joined: Dec 2011
Posts: 10
Likes: 0
From: Santa Barbara Ca
A lot of these references are full of errors and generalizations, probably taken from interchange lists which show what a part could be used for, but not necessarily what it is CORRECT for and were copied from one reference site to another, mainly from MORTEC. You will note things like misread and duplicate casting numbers and ranges of use that span for example,1956 to 1967 for a single casting number which is ridiculous. Very few casting numbers were used for multiple years as there were changes and improvements each year which resulted in a new casting number. The 3970010 casting is one of the few that had such a multiple year application, but it first appeared around april or May, 69 and continued through 75.
The 68 4 inch bore block used on 327 and 302 engines was 3914660 and 3914678. The 69 4 inch block (before the 010 came out) was 3932386 and 3932388 until the 3956618 came out around Jan 69.
Just take one of the multi year listings on your reference for example:
3959532 is shown as a 283 block for 56-67
First, there was no 283 in 56 and the first 283 was the 3731548 casting...do you really believe GM would cast the same block from 56-67 while still casting new ones just about every model year?
The 3959532 and other 39595XX series castings were warranty replacement blocks that were cast for the CE warranty replacement program that began in 68/69. These blocks were needed to service the older models since the small journal engines were no longer used in production.
The 68 4 inch bore block used on 327 and 302 engines was 3914660 and 3914678. The 69 4 inch block (before the 010 came out) was 3932386 and 3932388 until the 3956618 came out around Jan 69.
Just take one of the multi year listings on your reference for example:
3959532 is shown as a 283 block for 56-67
First, there was no 283 in 56 and the first 283 was the 3731548 casting...do you really believe GM would cast the same block from 56-67 while still casting new ones just about every model year?
The 3959532 and other 39595XX series castings were warranty replacement blocks that were cast for the CE warranty replacement program that began in 68/69. These blocks were needed to service the older models since the small journal engines were no longer used in production.
Le Mans Master
Joined: Apr 2006
Posts: 5,347
Likes: 36
From: San Clemente CA
Look on the rear of the block where it meets the bellhousing and about in line with the distributor. Look closely because you may have to wipe off some grease. You will see the date code which would be a letter and three numbers. The letter could be A for Jan, B Feb etc. The next two numbers are the month day , like 07 for the 7th. The last number will be the year. For instance mine is A265.....Jan 26, 1965.
Don
Don
Cruising
Joined: Dec 2011
Posts: 10
Likes: 0
From: Santa Barbara Ca
Look on the rear of the block where it meets the bellhousing and about in line with the distributor. Look closely because you may have to wipe off some grease. You will see the date code which would be a letter and three numbers. The letter could be A for Jan, B Feb etc. The next two numbers are the month day , like 07 for the 7th. The last number will be the year. For instance mine is A265.....Jan 26, 1965.
Don
Don
thanks
Last edited by NovaSS450hp; Dec 18, 2011 at 03:36 PM.
Le Mans Master
Joined: Apr 2006
Posts: 5,347
Likes: 36
From: San Clemente CA
