[wolfman2020]

Hi, I am trying to help my husband figure out what year/type engine is in his 73 Mustang. The mechanics who have it seem to be pretty sure it is a 302 and that it is an older model engine. The reason they think it is an older model is the number they found on the top of the back of the block behind the intake manifold is BH177861. Everything we found says the early model numbers start with a letter and the second digit is a number telling what year it is within the decade of the letter. None of these start with a B either. Can anyone help me with this? Thanks for your help!

[pcfrisch]

Hope this helps.

3 - Last digit of model year
F - assembly plant (F-Dearborn)
05 - Body code (01-Coupe, 02-Fastback, 03-Convertible, 04-Grandé, 05-Mach 1)
H - Engine code
100001 Consecutive unit number
Example:

3F05H100001

250cid1V6-cyl99 hp L Code
302cid2VV-8141 hp F Code
351cid2VV-8177 hp H Code
351cid4VV-8266 hp Cobra Jet Q Code

[wolfman2020]

Thank you for taking the time to help me out. From what you posted I still cannot figure out what the "B" is at the beginning of the id. Do you know? I saw it myself so I know there is not a number or letter that goes before it.

[fordman777]

If im not mistaking mam your looking in the wrong place and not really to be a smart elic or anything or affend anyone but these mechanics I wouldnt let change my oil the place you need to look would be under neath the car remove the starter and write down the numbers/letters you find and it is not hard at all to tell if its a 302 at all and the only motors that look alike is the 289, 302, and 351windsor with the exception on the windsor that the intake will be wider and have a higher deck height and to cut it short if you look at the thermostate housing it should be going straight into the intake on the front of it not the top but infront. And if im not mistaking they didnt put the 289 motors in that model they stopped producing them in 1968 but anyone correct me if im wrong. If you could post some pictures I could help you out with identifying if its a 302 or 351 if its the original motor. I hope I helped you. But tell your husband I said to cross his fingers and hope for a 351 or really a 351 cj. Also tell me what kind of carburator is on it 2 barrel, 4 barrel, stock, aftermarket. Just get the numbers and Ill try my best to help you out I wish you luck.

[FoxChassis]

It's an '82 model year block, from a Ford car, produced at Lorain Assembly. There were three vehicles produced at Lorain in '82: Thunderbird, Cougar, and Econoline. Cougar doesn't count in this thread because it's Mercury.

If the block is from a Thunderbird, it's not a 302. The Thunderbird's only V8 in '82 was the 4.2L/255. One year before and one year after you could get a 5.0L.

[FoxChassis]

Originally Posted by FoxChassis

It's an '82 model year block, from a Ford car, produced at Lorain Assembly. There were three vehicles produced at Lorain in '82: Thunderbird, Cougar, and Econoline. Cougar doesn't count in this thread because it's Mercury.

If the block is from a Thunderbird, it's not a 302. The Thunderbird's only V8 in '82 was the 4.2L/255. One year before and one year after you could get a 5.0L.

Sorry, I was a year off.

It's an '81 model year block, not '82. It's from either a Thunderbird or an Econoline van.

B = 1981
H = Lorain Assembly
177861 = 77,861st Ford to be assigned a VIN at Lorain Assembly

[EagleAutosports]

Fox Chassis knows numbers like that, he's very credible.

[fordman777]

Originally Posted by FoxChassis

Sorry, I was a year off.

It's an '81 model year block, not '82. It's from either a Thunderbird or an Econoline van.

B = 1981
H = Lorain Assembly
177861 = 77,861st Ford to be assigned a VIN at Lorain Assembly

Do you know if there is a website to decode and explain these numbers and letters I only know how to decode the numbers and letters where the starter bolts up and didnt even know about the others. Im also guessin you have done this a little more than a few times or you got a good resource.

[FoxChassis]

That is just the last eight characters (10 through 17) of a 1981 and later VIN. B = 1981 and the letters go up from there. I and O are skipped.

The tricky part is figuring out the model from the assembly plant code. For that you need to know what the plant code decodes to...

List of Ford factories - Wikipedia, the free encyclopedia

Then you need to figure out which model(s) were produced at that plant in that model year.

Lastly, you need to know that Ford cars start their PSNs with 100001 and go up to 599999, and Mercury and Lincoln cars start their PSNs with 600001 and go up to 999999.The PSN is reset back to the beginning every model year. They're also unique to each assembly plant, i.e. they are not intermingled with PSNs from other plants.