identifying block
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identifying block
My dad bought a complete engine a few years ago it is supposed to be an lt1 out of a 97 firebird. On the lefthand side of the block below the head is stamped VO308YST. Is this the casting # or is there another place i should look to see for sure if that is what the motor came out of? Or is there even a way to tell for sure what it came out of? Any help is appreciated.
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From: Hell was full so they sent me to NJ
Re: identifying block
Looking at the front of an LT1 block, you will see the numbers "327".... fairly large. That is the last three numbers of the block part number. On the back of the block, driver side on the area where the bell housing bolts, the is a stamped partial VIN of the vehicle it came out of.
F-Body and Corvette LT1's have aluminum heads. Caprice/Roadmaster/Fleetwood LT1's have cast iron heads.
F-Body and Corvette LT1's have aluminum heads. Caprice/Roadmaster/Fleetwood LT1's have cast iron heads.
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Re: identifying block
IIRC it will also say 5.7 on the rear of the block also. I believe in the B-body the smaller motor was also cast with a "327" # on side but the 5.7 (350 c.i.) is cast on the back of the Lt1
if Op's engine did come from a Firebird, it would be a LT1 5.7 motor with AL heads
if Op's engine did come from a Firebird, it would be a LT1 5.7 motor with AL heads
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Joined: Nov 1998
Posts: 71,086
From: Hell was full so they sent me to NJ
Re: identifying block
Correct info on L99 B-Body block, from Engine Builder magazine - Rebuilding the Chevrolet LT1:
My block - note 327 on the right side of the picture.
Courtesy of Shoebox:
BLOCKS
350 – There are two blocks, one with two-bolt mains and one with four-bolt mains. They both have the same 10125327 casting number, so there’s no sure way to know which one you have until you get the pan off. However, if it came out of a Corvette, it should be a four-bolt block, and if it came out of anything else, it was supposed to be a two-bolt. GM used the two-bolt block for everything but the Corvette because it had plenty of strength and it weighed a little bit less.
265 – There was only one block used for the 265 cid version of the LT1. It’s a 10168588 casting that had the numbers "4.3" cast on the side, too. It’s real easy to spot if the heads are off because of the small 3.74" bore.
350 – There are two blocks, one with two-bolt mains and one with four-bolt mains. They both have the same 10125327 casting number, so there’s no sure way to know which one you have until you get the pan off. However, if it came out of a Corvette, it should be a four-bolt block, and if it came out of anything else, it was supposed to be a two-bolt. GM used the two-bolt block for everything but the Corvette because it had plenty of strength and it weighed a little bit less.
265 – There was only one block used for the 265 cid version of the LT1. It’s a 10168588 casting that had the numbers "4.3" cast on the side, too. It’s real easy to spot if the heads are off because of the small 3.74" bore.
Courtesy of Shoebox:
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