Re: Block Casting Numbers
The block that started my research was the block that came in my 58 Corvette which was a CE 283 block casting 3959532. Then I acquired a 67 Nova which was an original 327 4 speed car. Since the L-79 was dropped for 67, the 327 option was the L-30 275 hp. The block that was in the car when I got it was an L-79 shortblock where the original L-30 had been, complete with high compression pistons. It was a real Chevy II block but the casting number was 3959538 and I couldn't find anything on this block either.
My research turned up a series of service castings which I initally thought were only for small journal service requirements after the SJ was out of production coinciding with the start of the CE warranty replacement program in late 68.
3959512 327 pass/truck
3959532 283 pass/truck
3959534 283 Chevy II
3050538 327 Chevy II
I reported my findings with documentation to the Mortec site which resulted in the addition of the 3959538 to the listing of Chevy II blocks.
'
Further reaearch turned up examples of the 3959512 4" bore block in both small journal and large journal and with 2 bolt and 4 bolt mains and with cannister or spin on oil filter configuration. The SJ versions had the crankcase vent provision on the back of the block and the LJ had the pad but it was not machined, just like the 68 blocks, The only 4 bolt main versions I saw examples of were as 302 engines in 69 Camaros, and some had original appearing assembly and VIN stamps with broach marks instead of the more typical CE stamp.The only explanation I could imagine other than counterfeit is the possibility that some 3959512 service blocks may have been used in production possibly due to the strike in 69. I'm guessing the service blocks may have been batch poured and stored for machining as necessary for service. It seems possible that some of these could have ended up in 69 Corvettes as 327 or even 350 versions. Has anyone seen that?
Both of my blocks and an NOS 3959534 Chevy II short block that I have pics of, had casting dates of A_9. All were identical to my 68 Chevelle 678 block (except for the recessed oil filter on the 538 block. All had the long stamp pad and All had CE9 plus the sequential numbers of the CE service blocks so naturally I assumed they were 69 service castings from the CE -5/50 warranty service program. The main difference I have found is that they have the last 3 digits of the casting number on the side of the block like the later one piece seal castings which makes me wonder if they were maybe 79 castings instead of 69, but that would mean they were still casting and selling SJ configured service blocks much later than I thought.
The earlier CE blocks I've seen did not have the side casting numbers so that is a prt of the puzzle I would like to solve to try to narrow down the casting date range on these oddball castings which so far have little documented history.
Anyway, that is the quest. I know it has little to nothing to do with actual production Corvette history, unless examples can be found in 69's, but it' still interesting to me.
The block that started my research was the block that came in my 58 Corvette which was a CE 283 block casting 3959532. Then I acquired a 67 Nova which was an original 327 4 speed car. Since the L-79 was dropped for 67, the 327 option was the L-30 275 hp. The block that was in the car when I got it was an L-79 shortblock where the original L-30 had been, complete with high compression pistons. It was a real Chevy II block but the casting number was 3959538 and I couldn't find anything on this block either.
My research turned up a series of service castings which I initally thought were only for small journal service requirements after the SJ was out of production coinciding with the start of the CE warranty replacement program in late 68.
3959512 327 pass/truck
3959532 283 pass/truck
3959534 283 Chevy II
3050538 327 Chevy II
I reported my findings with documentation to the Mortec site which resulted in the addition of the 3959538 to the listing of Chevy II blocks.
'
Further reaearch turned up examples of the 3959512 4" bore block in both small journal and large journal and with 2 bolt and 4 bolt mains and with cannister or spin on oil filter configuration. The SJ versions had the crankcase vent provision on the back of the block and the LJ had the pad but it was not machined, just like the 68 blocks, The only 4 bolt main versions I saw examples of were as 302 engines in 69 Camaros, and some had original appearing assembly and VIN stamps with broach marks instead of the more typical CE stamp.The only explanation I could imagine other than counterfeit is the possibility that some 3959512 service blocks may have been used in production possibly due to the strike in 69. I'm guessing the service blocks may have been batch poured and stored for machining as necessary for service. It seems possible that some of these could have ended up in 69 Corvettes as 327 or even 350 versions. Has anyone seen that?
Both of my blocks and an NOS 3959534 Chevy II short block that I have pics of, had casting dates of A_9. All were identical to my 68 Chevelle 678 block (except for the recessed oil filter on the 538 block. All had the long stamp pad and All had CE9 plus the sequential numbers of the CE service blocks so naturally I assumed they were 69 service castings from the CE -5/50 warranty service program. The main difference I have found is that they have the last 3 digits of the casting number on the side of the block like the later one piece seal castings which makes me wonder if they were maybe 79 castings instead of 69, but that would mean they were still casting and selling SJ configured service blocks much later than I thought.
The earlier CE blocks I've seen did not have the side casting numbers so that is a prt of the puzzle I would like to solve to try to narrow down the casting date range on these oddball castings which so far have little documented history.
Anyway, that is the quest. I know it has little to nothing to do with actual production Corvette history, unless examples can be found in 69's, but it' still interesting to me.
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