Help with Engine Code Identification

[focodave]

Can anyone tell me what year/model a 138AR.1 twin cam would have come from?

[131]

As long as you're looking at the numbers stamped into the block, not the cast numbers, the closest on this list is a 125tc, which has one of the best heads for porting, performance work.

http://www.netikka.net/ville.vieri/tc/tclist.htm

[focodave]

Mick,
Thank you very much.
I searched the web high and low and could not find that number anywhere. (I guess I didn't search enough, though)
That's exactly what I needed.
Dave