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Check out the bottom numbers on this 44U

Post Mon Feb 08, 2010 1:05 pm

Posts: 349
Location: Champaign-Urbana, IL
Hey -

Nobody's posted an interesting engine number question for a while, so here's one ... Not really a question, but more of an observation.

I think this case would go as un-touched and legal just about anywhere, but check out the matching line-bore numbers ... There are three different "fours" used!

Just throwing it out there ...



I can "sort of" understand it.
1940 is a new casting for both sides; perhaps they decided to hit all the cases with a single "4" immediately (whenever they were cast, could have been as early as 1939) so that none would accidentally be used o replace a 37-39.
Once the year was decided ("these 500 sets will be 1944) the 2nd 4 was added (8/43-?), still to individual cases.
Once the pairs were matched, a different stamp was used for the production sequence - but the same set for both sides.
If you buy this, the clean stamp and absence of surface disturbance make this legal IMHO.

Posts: 3159
Location: Central Illinois, USA
I find it very interesting, as it contains the 'open-back' four stamp.
The VIN looks fine, so the question becomes: Why would anyone go to great trouble to fudge the production numbers?

I suspect the open back four may be legit more often than allowed.


Posts: 2688
Location: Los Angeles, CA
They are legit numbers.

Posts: 349
Location: Champaign-Urbana, IL
I agree, and I think Panic's explanation is a reasonable one. Thanks.


Posts: 49
All 1944 produced crankcases, 45, 61, & 74, have this same combination of fours for 44 in the crankcase production number. You will find this combination of bottom numbers on all 1944 motors (except very-early 1944 which have late 1943 bottom numbers) and all early-1945 motors.

Of note, the first four in 44 of the crankace production number is the exact same four as used for the decade number (4) in all mid-1941 through early-1947 crankcase production numbers.

Also, from the offset between the decade 4 and the rest of the production number on the 1941-1947 bottom numbers that I have seen, I am led to believe that the decade 4 was stamped at an exact point in crankcase machining and mating with the rest of the bottom number stamped at a later point.

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