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Discussion Starter · #1 ·
Hi All,

I'm new to the forum and re-living my younger days with a recently acquired 72 Formula 350.

The engine code (YR) and the head code (7H1) are correct for the year as is the carburetor, but I

can't correlate the engine unit code above the engine code. Its 023387 and there appears to be

a partial etching that looks like a "C" in front of it but not in the same spacing of the code digits.

Am I trying to do something that can't be done? Any listings for these unit codes I can check?

I haven't had a chance to get it on a lift yet to look for other numbers.

Thanks

Tonino
 

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Admin - Firebird lover
1968 Convertible 400, 200 4R, 1971 Formula 400 M-22 Rock Crusher, 1984 Trans Am...........
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The Block Casting number should be 481990 for 1972 YR block. 7H1 would be the correct Heads. Carb code should 7042062. There are no casting numbers close to yours for YR block.

original specs:

160/175 HP

8.0 compression ratio

2 bbl carb

Automatic cars only

Cam # 555

Towards the bottom of the block below the Engine Code and Casting Code, you should see a partial VIN. It should match the last digits of your windshield VIN and tranny VIN.
 

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Discussion Starter · #3 ·
Hi "Garage Gopher",

Thank you for the reply. It'll be awhile before I can get to the partial vin lower on

the block. Just got the engine running correctly and declared victory. Then just

curious, what is the "unit" number above the code? Should it be 481990 or would

this number be somewhere else on the block?

Thanks

Tonino
 

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Discussion Starter · #4 ·
Looks like the "Unit Number" stamped above the "YR" code on the right side of the block

is the engines serial number under the "YR" code. This number has nothing to do with

either the vin, casting number or anything else. It is stamped into the block at the foundry

where it was cast. I did try to find a list of serial numbers for my 72 YR engine but they

either don't exist or I just haven't been able to locate one yet. And there you have it.

Tonino
 

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Most consider these motor unit or engine serial numbers to be of very little significance in identifying a Pontiac engine. They are simply sequential numbers for a given run of engines. They are not related to the vehicle VIN number, or the engine code(usually 2 digits) which is just below the motor unit or serial number. And they are not related to the block casting number.

http://www.wallaceracing.com/form.php
 

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Discussion Starter · #6 ·
Thanks for the reply Ponyakr.

I know that now! Was never quite sure what "unit code"

meant in all the texts concerning same. Right now I'm enjoying my Formula 350 and

reliving some memories of the new Ram Air IV we had back in the day. Next project is

to troubleshoot the HVAC vacuum system then move on to restoring the AC system

back to operation.

Tonino
 
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