340 T/A AAR exhaust manifold date code?

[Monsterzero]

I was looking at a pair of exhaust manifolds for a '70 T/A motor. the date code #s are pictured below. What are the dates on these manifolds? One reads 10390 or 10890 and the other reads 11140. Would they be correct for a car assembled on 4/16/70?

[6bblgt]

I think that one is "11149" Friday 11/14/1969

do you have a close pic of the other date?

[Monsterzero]

I think you're right. Sorry, I don't have a close-up picture of the other manifold.

[70 Challenger Lover]

How about this code?

[6bblgt]

looks like 05 28  I think it's just missing a digit 

Wednesday 05/02/1968
Sunday 05/12/1968
Wednesday 05/22/1968

[70 Challenger Lover]

I was trying to figure that out too. Is that a zero at the very end? If so then I guess it would be May 28, 1970?

[6bblgt]

there is a screw at each end

[70 Challenger Lover]

I see that at the beginning but not at the end. I don't think it's really a screw though. I've seen that casting mark on other manifolds though not sure what it means. Once I get it to me in a few days, I can head blast it and hopefully read it better.

[6bblgt]

  here's what I see 

"8" & "9" are sometimes hard to distinguish in castings and the 05 28 could be May 28th of an unknown year (5/28/??); you'd have to collect dozens of 340 manifold casting examples including some from known original to engine/car to find any consistencies in the format used

but I believe by the time the T/A AAR cars came out, the exhaust manifolds had the part number on the back/engine side 

[70 Challenger Lover]

Good eye, you might be right. Just bought mine the other day off eBay so I'll have to blast it and post what I see with the gunk cleaned off.

In the end, date doesn't matter in my case. I was just curious. I've been looking for an affordable decent original set for years to go with a 340 motor I'm storing. Someday I'll find the right car to do a nice build on. The passenger side manifold seems to be the tough one to find.

[Bossgold]

I asked this questions a few months back and my understanding was many of the AAR/T/A exhaust manifolds had no dates codes but just a casting number facing the inside of the engine side.

[70 Challenger Lover]

here's what I see 

"8" & "9" are sometimes hard to distinguish in castings and the 05 28 could be May 28th of an unknown year (5/28/??); you'd have to collect dozens of 340 manifold casting examples including some from known original to engine/car to find any consistencies in the format used

but I believe by the time the T/A AAR cars came out, the exhaust manifolds had the part number on the back/engine side 

Got the manifold delivered today and you're right that it's a screw head on either side of the date but no year. I never thought about those screw heads before as actually being screws. Is that some fastener the foundry used in the mold to hold the dates in?

The manifold is in super condition. Even the flapper works nice.