LS5 - verifying authenticity
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 793
Likes: 10
From: Grafton MA
LS5 - verifying authenticity
There are a lot of great posts on the forum on how to verify authenticity of an LT-1 (have one so know them pretty well). I'd like to know what to look for to verify an LS5.
Looking at a '72 and verified the following:
- VIN has "W" engine code as it should
- VIN on windshield pillar matches engine pad
- stamping broach marks look good.
- engine casting date about 1 week from assembly date
- engine assembly date a couple weeks before body assembly date (on trim tag)
- heavy duty radiator
- heavy duty differential side yokes...not the u-bolt style
- gas tank has been replaced so not much to verify there
- engine label on center console indicates 454 (although could have been easily be replaced)
There is no POP or tank sticker with the car. But since it's a '72 I feel more comfortable knowing that the VIN indicates LS5 and the other things mentioned above add up also. Anything else to look for?
Thanks,
Paul
Looking at a '72 and verified the following:
- VIN has "W" engine code as it should
- VIN on windshield pillar matches engine pad
- stamping broach marks look good.
- engine casting date about 1 week from assembly date
- engine assembly date a couple weeks before body assembly date (on trim tag)
- heavy duty radiator
- heavy duty differential side yokes...not the u-bolt style
- gas tank has been replaced so not much to verify there
- engine label on center console indicates 454 (although could have been easily be replaced)
There is no POP or tank sticker with the car. But since it's a '72 I feel more comfortable knowing that the VIN indicates LS5 and the other things mentioned above add up also. Anything else to look for?
Thanks,
Paul
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
Looks good so far but a few more things:
Radiator - larger copper radiator without radiator cap
Expansion Tank - must have aluminum (no A/C) or brass (A/C) on right inner fender
Sway Bars - must have 15/16" and 9/16" bars
Also see if you can get the numbers off the trans and if they match
Be nice if you could check the frame stamp but guess that won't happen
Radiator - larger copper radiator without radiator cap
Expansion Tank - must have aluminum (no A/C) or brass (A/C) on right inner fender
Sway Bars - must have 15/16" and 9/16" bars
Also see if you can get the numbers off the trans and if they match
Be nice if you could check the frame stamp but guess that won't happen
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 793
Likes: 10
From: Grafton MA
Thanks.
It does have the expansion tank (no AC). I think it's aluminum...maybe you can tell from the pictures. I didn't check that closely when i saw the car up close (maybe should have posted this thread before seeing the car)
Transmission numbers match...and it is an M21
I don't believe there was a cap on the radiator (see pic)
I checked but couldn't see the VIN on the frame. I believe it's the original frame, but would probably have to pull the tire and look closer to see the VIN.
Intake manifold and block casting number checked out also.
Unfortunately no docs on the car. The fact that it's a '72 helps put my mind at ease a little since W is in the VIN. Since there are no docs to support this, that is why i'm asking for other signs.
Thanks,
Paul
It does have the expansion tank (no AC). I think it's aluminum...maybe you can tell from the pictures. I didn't check that closely when i saw the car up close (maybe should have posted this thread before seeing the car)
Transmission numbers match...and it is an M21
I don't believe there was a cap on the radiator (see pic)
I checked but couldn't see the VIN on the frame. I believe it's the original frame, but would probably have to pull the tire and look closer to see the VIN.
Intake manifold and block casting number checked out also.
Unfortunately no docs on the car. The fact that it's a '72 helps put my mind at ease a little since W is in the VIN. Since there are no docs to support this, that is why i'm asking for other signs.
Thanks,
Paul
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
Yeah that looks good
The M21 is a huge plus since it was only available on LT1 and LS5 in 72
Radiator, fan, shroud and tank all look good
Exhaust manifolds have AIR holes so that is good too
Can you get the rear axle codes?
The M21 is a huge plus since it was only available on LT1 and LS5 in 72
Radiator, fan, shroud and tank all look good
Exhaust manifolds have AIR holes so that is good too
Can you get the rear axle codes?
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 793
Likes: 10
From: Grafton MA
I don't have the rear axle codes, supposedly 355 rear. I went looking for the TI amp like my '71 LT-1 has and then realized it wasn't on the '72 LS5. Thanks for the insight...i am thinking it's the real deal but always good to get more opinions before forking over cash 
. Biggest negative is the car is not the original color. Paint is nice though.
. Biggest negative is the car is not the original color. Paint is nice though.
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Drifting
Joined: Feb 2005
Posts: 1,438
Likes: 2
From: Melrose Florida
Paul,
I'm pretty sure '72s had an emissions/tuneup label on the cowl near the brake booster, should have an identifying code (letters or numbers) to identify engine, and maybe trans.
Steve
I'm pretty sure '72s had an emissions/tuneup label on the cowl near the brake booster, should have an identifying code (letters or numbers) to identify engine, and maybe trans.
Steve
There are a lot of great posts on the forum on how to verify authenticity of an LT-1 (have one so know them pretty well). I'd like to know what to look for to verify an LS5.
Looking at a '72 and verified the following:
- VIN has "W" engine code as it should
- VIN on windshield pillar matches engine pad
- stamping broach marks look good.
- engine casting date about 1 week from assembly date
- engine assembly date a couple weeks before body assembly date (on trim tag)
- heavy duty radiator
- heavy duty differential side yokes...not the u-bolt style
- gas tank has been replaced so not much to verify there
- engine label on center console indicates 454 (although could have been easily be replaced)
There is no POP or tank sticker with the car. But since it's a '72 I feel more comfortable knowing that the VIN indicates LS5 and the other things mentioned above add up also. Anything else to look for?
Thanks,
Paul
Looking at a '72 and verified the following:
- VIN has "W" engine code as it should
- VIN on windshield pillar matches engine pad
- stamping broach marks look good.
- engine casting date about 1 week from assembly date
- engine assembly date a couple weeks before body assembly date (on trim tag)
- heavy duty radiator
- heavy duty differential side yokes...not the u-bolt style
- gas tank has been replaced so not much to verify there
- engine label on center console indicates 454 (although could have been easily be replaced)
There is no POP or tank sticker with the car. But since it's a '72 I feel more comfortable knowing that the VIN indicates LS5 and the other things mentioned above add up also. Anything else to look for?
Thanks,
Paul
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 330
From: Indy Indiana
carb should be 7042217 (4-speed)
or 7042216 ( auto )
emission label by brake master cyl should be a LZ code
front springs should have a lable hanging from them either HV, HU or EA
check your date codes on manifolds too to confirm it is not a pieced together big block..
but really, if your vin states big block, then it is big block car... plenty of ways to replace the original engine and fake that the replacement is original, but if all else is ok then it looks good...
or 7042216 ( auto )
emission label by brake master cyl should be a LZ code
front springs should have a lable hanging from them either HV, HU or EA
check your date codes on manifolds too to confirm it is not a pieced together big block..
but really, if your vin states big block, then it is big block car... plenty of ways to replace the original engine and fake that the replacement is original, but if all else is ok then it looks good...
