GM Crate short block info(Joe Lucia)

[Dennis D.]

Does anyone know the details of this crate short block? Was told it is an original GM LT-1 short block.
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[Joe L.]

Re: GM Crate short block info(Joe Lucia)

Does anyone know the details of this crate short block? Was told it is an original GM LT-1 short block.
[ATTACH=CONFIG]100810[/ATTACH]
[ATTACH=CONFIG]100811[/ATTACH]

Dennis------


It could be. Or, it could be an L-46 short block. I cannot discern the last 4 digits of the part number stenciled on the crate. That's critical to ID.

[Dennis D.]

Re: GM Crate short block info(Joe Lucia)

Dennis------


It could be. Or, it could be an L-46 short block. I cannot discern the last 4 digits of the part number stenciled on the crate. That's critical to ID.

Thanks Joe. I thought possibly L46 as well. Im told solid cam though.
Isn't that number on the block the same one that's on the crate?
. Would there be a timing cover and oil pan?

[Joe L.]

Re: GM Crate short block info(Joe Lucia)

Thanks Joe. I thought possibly L46 as well. Im told solid cam though.
Isn't that number on the block the same one that's on the crate?
. Would there be a timing cover and oil pan?

Dennis------


No, the number on the crate is the part number for the engine assembly. That's what's needed to identify the assembly. The number on the block is the casting number for the block. There's no way it would be on the crate even if the engine within was a bare block. Both numbers begin with "397" and, possibly, "3970". But, the rest of the number is different.

Short blocks were usually not supplied with timing cover or oil pan. I highly doubt that this one includes those parts.

[Keith B.]

Re: GM Crate short block info(Joe Lucia)

since its a short block wouldn't it have a assembly stamp with suffix code?

[Patrick B.]

Re: GM Crate short block info(Joe Lucia)

I think a short block would have a CE number. If it comes with lifters you can check whether they are solid or hydraulic.

[Dennis D.]

Re: GM Crate short block info(Joe Lucia)

Couple more pics. Dont think I see cam lobes.

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[Joe L.]

Re: GM Crate short block info(Joe Lucia)

since its a short block wouldn't it have a assembly stamp with suffix code?

Keith------


No suffix code. Suffix codes denote a complete engine configuration. This short block could have been built into at least 6 engine configurations (Corvette and Camaro).

[Joe L.]

Re: GM Crate short block info(Joe Lucia)

Couple more pics. Dont think I see cam lobes.

[ATTACH=CONFIG]100812[/ATTACH][ATTACH=CONFIG]100813[/ATTACH]

Dennis------


I don't see cam lobes, either. Short blocks were supplied with an installed camshaft. So, it's been removed in the case of this short block.

If the part number on the crate is 3970653, which is likely, then it's an L-46. Of course, without the cam it could now be configured into either and L-46 or LT-1 depending upon which cam was installed.

The 1970 LT-1 short block was GM #3966921. The number on the crate is definitely not that number.

[Patrick B.]

Re: GM Crate short block info(Joe Lucia)

Pink rods look like LT-1.

[Joe L.]

Re: GM Crate short block info(Joe Lucia)

Pink rods look like LT-1.

Patrick------


Both L-46 and LT-1 used the same connecting rods. L-82, too.

[Dennis D.]

Re: GM Crate short block info(Joe Lucia)

Have better pic of crate number. If this is a L46, am I correct in the cam is the only difference in the short block.
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[Lawrence M.]

Re: GM Crate short block info(Joe Lucia)

Yes the only difference is the cam. Both LT-1 and L46 used the same forged crank, pink rods and 11-1 pistons .

[Joe L.]

Re: GM Crate short block info(Joe Lucia)

Have better pic of crate number. If this is a L46, am I correct in the cam is the only difference in the short block.
[ATTACH=CONFIG]100819[/ATTACH]

Dennis------


Yes, the number cinches it and, yes, the only difference between L-46 and LT-1 partial engines ("short blocks") is the camshaft. One interesting side-note: L-46 was Corvette only. LT-1 was both Corvette and Camaro.

[Dennis D.]

Re: GM Crate short block info(Joe Lucia)

Thanks all for confirming
L46 I know. Had one for 45 years. LT-1 is somewhat different, obviously not in the short block.