What heads? 1941 half ton.

[Kube]

Originally Posted by JWL

The heads installed on 99.9999% of vehicles like your wife's truck had the letter "A" usually in the middle area. These should be inexpensive and relatively easy to find.

Not if it is a Mercury engine.

[rotorwrench]

I think the initial Mercury cars used the Big "A" heads for a while in the 1939 start up year. All I have to go by is the ole 38 thru 41 parts book so that's as far as it goes. They will work on there though. I don't think the Mercury engines were relieved but I don't know that for certain. Trucks were the ones that needed the relief to lower the compression ratio.

[Kube]

Originally Posted by harley

I took a closer look at the heads I have today. They have the big T embossed on them but they are marked 81T-6049 and 81T-6050. The block has 99 stamped close to the front on the intake deck. I know it is a 239cu. Sorry they are not 99T heads.

81T heads were installed (originally) on the Ford engines.

[V8COOPMAN]

Originally Posted by Kube

81T heads were installed (originally) on the Ford engines.

It would possibly help folks to at least have an idea of what these parts REALLY are if they would put some effort into learning Ford's early parts numbering system. Numbers like "81T", "81A" and "99" actually signify some pretty basic, yet revealing information. The "81" prefix indicates two things........"8" (the first position) indicates 1938 as being the FIRST year of release for that specific part. The "1" indicates that it is a FORD part specifically (and POSSIBLY also used on Mercs IF the Merc uses an identical part, although Mercs didn't initially appear until 1939). A better example would be 1940 brake pedals. A FORD pedal would have an "01A" prefix, where-as a Mercury would have a "09A" prefix on it, as they were slightly different in design. The "T" (81T) indicated that it is a part for a "big" Truck......NOT a pick-up, which would be indicated by a "C" (81C) for "COMMERCIAL", which a 1/2-ton pick-up falls under. "81A" would indicate a 1938 (8) FORD (1) PASSENGER CAR (A).

So, what is this "99" stuff? Well, the FIRST "9" (REMEMBER: First position) indicates 1939 as FIRST year of release. The SECOND "9" indicates that it is specifically a MERCURY part. Once you start recognizing these numbering sequences, you can begin to at least start guessing pretty-closely as to what some of these common parts are. DD

[rotorwrench]

Actually the second 9 just represents the 239 CID 95 HP engine size. The Mercury was in the 99A catagory but so were all the Fords after the war. As Kube mentioned, there are some rare situations where the Ford cars carried the 99A VIN before the war but not too many I'm sure. Big trucks could go either way (221 or 239) but they would be the 99T catagory if they had the 239 CID engine.

The second number in the 221 engine catagory was generally always a 1 after the V8-60 came on line in 1937.