Tim -- Apparently, per the posts above, the "T" means the block was cast at Tonawanda, NY. A Flint, MI block would have an "F"
Mike -- Concur -- could be that we are barking at ants, here ... Another data point is that my truck's main journals were cut for the newer style bearings --
Why this matters. Not sure if that has anything to do with the present discussion.
Also possibly important is that so far, *my* 261 is the only one we've seen (in this discussion) without the bars. It might be interesting and informative if someone else could chime in who has a bar-less 261. Mine can't be the only one ... If it is, I probably owe 48bigtrucks more money ...
I think, if nothing else, we *can* say that not all 261's have Captain's bars and thus, they should not be used as the sole identifier. Absence of Captain's Bars may *indicate* that it isn't a 261, but isn't conclusive (as my engine proves)-- the casting code is still the only way to know for sure.
Sorry if I took this conversation down a rabbit hole. I needed a distraction.
