1969 3963512

[Roger G.]

I have heard that the only difference between a 69 427/390 and 427/400 is the tri carb setup.

In corvette by the numbers, it states that the both use the same block (3963512)...but the 390 is a two bolt main and the 400 is a 4 bolt.

Did the 427/400 have a 4 bolt main?

[Patrick B.]

Re: 1969 3963512

the 427/400 used the same 2 bolt block as a 427/390

[Gary H.]

Re: 1969 3963512

The engines are basically identical, but the 400 uses a 4 bolt main.

[Dick W.]

Re: 1969 3963512

The engines are basically identical, but the 400 uses a 4 bolt main.

. Most, if not all 400 HP engines were 2 bolt main blocks. If I we we looking at a 400, and saw the telltale signs of a 4 bolt block, I would have to have good provenance to believe it to be original

[Clem Z.]

Re: 1969 3963512

. Most, if not all 400 HP engines were 2 bolt main blocks. If I we we looking at a 400, and saw the telltale signs of a 4 bolt block, I would have to have good provenance to believe it to be original

if you see a 512 block with 4 bolts mains it should have the the pipe fittings on the side of the block above the oil filter for the external oil cooler

[Dick W.]

Re: 1969 3963512

if you see a 512 block with 4 bolts mains it should have the the pipe fittings on the side of the block above the oil filter for the external oil cooler

DAT be the telltale signs I wuz talking about

[Roger G.]

Re: 1969 3963512

This is out of the book- Corvette by the Numbers, it reads like it was standard on 427/400, hence the confusion

IMG_0305.jpg

[Dick W.]

Re: 1969 3963512

This is out of the book- Corvette by the Numbers, it reads like it was standard on 427/400, hence the confusion

[ATTACH=CONFIG]43123[/ATTACH]

If it is one internet, it must be the truth, NOT. That is wrong info.

[Roger G.]

Re: 1969 3963512

If it is one internet, it must be the truth, NOT. That is wrong info.

Its amazing the amount of misinformation out there. This is the second mistake I've found in a respected reference in the past week.

Corvette by the Numbers is the only authoritative reference for identifying and verifying, by casting number, the correct engine and drivetrain parts for your exact model Corvette. From the author of the highly acclaimed Chevrolet by the Numbers book series, Corvette by the Numbers documents part casting numbers and applications using original source material from General Motors Archives.

[Ray K.]

Re: 1969 3963512

Both the 427 390HP and the 400HP were hydraulic camshaft engines and used the 2 bolt main 512 block. The solid lifter camshaft 435HP used the 512 4 bolt main block with the appropriate fittings for an external cooler attachment.

[Dick W.]

Re: 1969 3963512

Tank stickers show L 36 and "convert to 400 HP" if my memory does not fail me

[Patrick B.]

Re: 1969 3963512

This assertion that 427/400 used a 4 bolt block is a systematic error in Alan Colvin's book. It is also made in the discussion of 351, 321, 439 and 270 blocks, and even in the discussion of 942 blocks ground and stamped 351 very early in the 67 model year. It implies that no 400hp ever had a 2 bolt block which is clearly wrong.

[Jack C.]

Re: 1969 3963512

Tank Sticker info:

02L68AA 390 TO 400HP EQUIP
02L36AA 390HP TURBO-JET V8

[William C.]

Re: 1969 3963512

i once owned a '68 427-400, purchased for original owner. Was sitting way to long so I rebuilt the engine, a 2-bolt block for sure......

[Clem Z.]

Re: 1969 3963512

any good auto machine shop can add 4 bolt main caps to any 512 block if you want it