351C Motor Identification

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Michael O’Harran

Well-known member
Joined
Jan 4, 2022
Messages
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Location
Maryland region south of DC
My Car
1972 Mach 1 Mustang 351C
Currently Under Restoration
I am doing a full restoration of my 1972 Mach 1. The motor is now done. It’s a 1972 351C. We picked it thinking it was an R Code from 1972 matching my car as close as possible. But I can’t research the answers to me questions about it, hence my finally joining a Mustang site. Hoping for help. My Mach 1 is an R Code. The original motor and trans were lost to time. This motor has cast mold of
D2AE-CA
2A20
So I think I researched that to be a 351C with a 4 bolt main and the 2A20 is 1972April20. My Mach 1 was actually assembled on 1972April13. So close. I have seen some back and forth on it could be either a 2 or 4 bolt main. I don’t know. Now the partial vin stamp is what is messing me up. I’ve attached it below. It reads 2A220710 I think. From what I researched the 1972 351C should be either a Q or an R Code. BUt now I’m seeing the letter on the motor could be from the plant it was built at. I don’t see A as an option. I want to be able to speak intelligently about my car but haven’t worked this part out yet any help would be greatly appreciated. Thanks C2A46193-6A37-4DAA-9144-CE973C1FE894.jpeg
 

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I am doing a full restoration of my 1972 Mach 1. The motor is now done. It’s a 1972 351C. We picked it thinking it was an R Code from 1972 matching my car as close as possible. But I can’t research the answers to me questions about it, hence my finally joining a Mustang site. Hoping for help. My Mach 1 is an R Code. The original motor and trans were lost to time. This motor has cast mold of
D2AE-CA
2A20
So I think I researched that to be a 351C with a 4 bolt main and the 2A20 is 1972April20. My Mach 1 was actually assembled on 1972April13. So close. I have seen some back and forth on it could be either a 2 or 4 bolt main. I don’t know. Now the partial vin stamp is what is messing me up. I’ve attached it below. It reads 2A220710 I think. From what I researched the 1972 351C should be either a Q or an R Code. BUt now I’m seeing the letter on the motor could be from the plant it was built at. I don’t see A as an option. I want to be able to speak intelligently about my car but haven’t worked this part out yet any help would be greatly appreciated. Thanks View attachment 58282
It is a motor from a 72 or 73 car built at the Atlanta assembly plant ( 2 for 72 and A for the Atlanta plant). The rest is the serial number part of the VIN. This number is typically stamped somewhere on a machined surface on the driver's side top rear of the block as the engine is matched up to the car.
Sorry to say that the engine is from a Torino or Montego or a Ranchero which were all built at the Atlanta assembly plant.

From what I have read, casting # D2AE-CA blocks came in both 2 and 4 bolt mains (Ford part #s: D1ZE-A & D3ZZ-A). The four bolts were the CJ "Q" code and High Output "R" code engine blocks. I have two of these blocks now both are two bolt and one of them is from the Atlanta Plant. From what I have read the D2AE-EA block was only a 4 bolt (ford part # D1ZZ-D) used in 1972 cars. here are a few examples...Block VINs1x.jpg
 
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The number stamped on the rear of block is for the car only. 2 is for a 72 car A is for Atlanta plant where car was assembled 220710 was 120,710 car built in72. Ford units start at 100,000 Mercury starts at 500,000
 
You said the motor is now done. Whoever did the work on it should be able to tell you if it's a 2 or 4 bolt block, unless you meant it's done in, as in kaput.
 
You said the motor is now done. Whoever did the work on it should be able to tell you if it's a 2 or 4 bolt block, unless you meant it's done in, as in kaput.
Or just painted. If it's not in the car, not hard to remove the pan and check. My guess would be it's a 2 bolt, buuut I could be wrong.
2A20 is the date code 72/Jan/20. One of my listings shows CA to be a 4 bolt CJ motor, EA for the HO, but another listing (MustangTek) show it could be either, but under 4 bolt, it shows Cobra Jet, HO Mustang-Torino. The confusion continues!
 
Along with the partial VIN stamp on the driver's side rear block face there is an engine assembly date code stamped into the front face of the block. I am hazy on where the exact location is on 351C, I think its located per below but I'm not 100%
351C Engine Assembly Date Code Location.JPG
As far as dating things, you would want dates that precede your vehicle build date.

Earliest: block casting date (the date code by the starter)
Next: engine assembly date (front face of block)
Finally: veh. build date
 
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Or just painted. If it's not in the car, not hard to remove the pan and check. My guess would be it's a 2 bolt, buuut I could be wrong.
2A20 is the date code 72/Jan/20. One of my listings shows CA to be a 4 bolt CJ motor, EA for the HO, but another listing (MustangTek) show it could be either, but under 4 bolt, it shows Cobra Jet, HO Mustang-Torino. The confusion continues!
Oh the A is not April, but January for the 1st month, first letter?
 
Along with the partial VIN stamp on the driver's side rear block face there is an engine assembly date code stamped into the front face of the block. I am hazy on where the exact location is on 351C, I think its located per below but I'm not 100%
View attachment 58310
As far as dating things, you would want dates that precede your vehicle build date.

Earliest: block casting date (the date code by the starter)
Next: engine assembly date (front face of block)
Finally: veh. build date
I’ll relook at the front motor for the assembly date. Thanks
 
No problem, I have a J-code car missing its engine so I have been trying to find date code correct parts for it.

And to confirm, yes for date codes A is January, B Feb and so on skipping I as it gets confused with 1...

So your block casting date code is Jan. 20, 1972.
 
In 1972, the only plant building Mustangs was the Dearborn plant, which would be an "F" in the partial VIN stamp. The Atlanta plant built the Torino / Montego lines. Since your sequential number is 220710, it came from one of models in the Torino lineup, since as previously mentioned, Mercury VINs start at 5xxxxx.

Oh the A is not April, but January for the 1st month, first letter?

The Ford casting date system is Year - Month - Day. Months start at January with "A", and skip "I" ending at "M" for December.
 
Or just painted. If it's not in the car, not hard to remove the pan and check. My guess would be it's a 2 bolt, buuut I could be wrong.
2A20 is the date code 72/Jan/20. One of my listings shows CA to be a 4 bolt CJ motor, EA for the HO, but another listing (MustangTek) show it could be either, but under 4 bolt, it shows Cobra Jet, HO Mustang-Torino. The confusion continues!
Just confirmed 4 bolt
 
It is a motor from a 72 or 73 car built at the Atlanta assembly plant ( 2 for 72 and A for the Atlanta plant). The rest is the serial number part of the VIN. This number is typically stamped somewhere on a machined surface on the driver's side top rear of the block as the engine is matched up to the car.
Sorry to say that the engine is from a Torino or Montego or a Ranchero which were all built at the Atlanta assembly plant.

From what I have read, casting # D2AE-CA blocks came in both 2 and 4 bolt mains (Ford part #s: D1ZE-A & D3ZZ-A). The four bolts were the CJ "Q" code and High Output "R" code engine blocks. I have two of these blocks now both are two bolt and one of them is from the Atlanta Plant. From what I have read the D2AE-EA block was only a 4 bolt (ford part # D1ZZ-D) used in 1972 cars. here are a few examples...View attachment 58287
Able to work it down to 72 Torino with 4 bolt main
 
Able to work it down to 72 Torino with 4 bolt main
A CA 4 bolt is a good pic. How did you confirm it has a 4 bolt? I Learned something ....I did not know the mercury vin serial numbers started with 5xxxxx.
 
A CA 4 bolt is a good pic. How did you confirm it has a 4 bolt? I Learned something ....I did not know the mercury vin serial numbers started with 5xxxxx.
We got the motor, tore it down and built it up with the heads, distrib, and carb from my 351M build that I replaced that with. So I just asked my mechanic and he knew right away. So it was the first hand knowledge that I don’t know how else you prove.
 
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