1969 427 block 3963512

[Ed M.]

Can anyone tell me when the 3963512 block was initially installed in 1969 427 Corvettes? The NCRS Spec. Guide says that this casting number MAY also have been used. In Colvin's "Chevrolet by the Numbers," it says 512 block production began in October 1968 and ran thru the '71 model year (as a 454). It also says the block was redesigned 11/17/69, at which time the casting date was moved from near the starter to the rear bellhousing flange.

I have seen 512 blocks with August '69 dates on the rear bellhousing flange.

So, all you eagle-eye judges, when did the Corvette first receive the 512 block? And were the dates different for the introduction of the 2-bolt and 4-bolt versions?

Thanks Ed McGee

[Roy S.]

Re: 1969 427 block 3963512

Ed,

I owned a L89 with a 512 four bolt block dated Feb 69, the car was actually built in late June or early July. there may have been 512 blocks used even earlier that is just an example I am aware of

[Roy S.]

Re: 1969 427 block 3963512

Ed,

I owned a L89 with a 512 four bolt block dated Feb 69, the car was actually built in late June or early July. there may have been 512 blocks used even earlier that is just an example I am aware of

[Trebor M #25911]

Re: 1969 427 block 3963512

My 69 block is a #270 and the car has a Nov.1968 build date. The #270 had a short production time and was used between the #439 and the #512. My guess is that any 69 big block built after January 69 should be a 512 block, accept the L-88. I would say between late Nov. to Dec.of 1968 there was a mixed bag. This is just my opinion and I'm sure people out there could be more specific to your question. Good luck.

[Trebor M #25911]

Re: 1969 427 block 3963512

My 69 block is a #270 and the car has a Nov.1968 build date. The #270 had a short production time and was used between the #439 and the #512. My guess is that any 69 big block built after January 69 should be a 512 block, accept the L-88. I would say between late Nov. to Dec.of 1968 there was a mixed bag. This is just my opinion and I'm sure people out there could be more specific to your question. Good luck.

[steve styllis]

Re: 1969 427 block 3963512

My car is a dec 68 build and uses the 270 block cast 9-4-68. Through my investigations I can say that the 270 blocks were used into late january 69 and probably well after that, at least in the 4 bolt configuration.

Steve

[steve styllis]

Re: 1969 427 block 3963512

My car is a dec 68 build and uses the 270 block cast 9-4-68. Through my investigations I can say that the 270 blocks were used into late january 69 and probably well after that, at least in the 4 bolt configuration.

Steve