yankingeorgia Wrote:
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> It was an attempt to split the piston forces and
> resultant hammer blow of a given wheel arrangement
> and allow for smaller reciprocating parts, albeit
> while having to maintain two sets of cylinders and
> a lot more plumbing.
>
> Thus you get a split 4-8-4 as a 4-4-4-4 and a
> split 4-10-4 as a 4-4-6-4.
>
> The Q1 was a one-off. The unfortunate placement of
> the rear cylinders at the rear of the second
> engine put them and the crosshead at the dirtiest
> and most cramped location on the locomotive. It
> also restricted the firebox size. That's why the
> Q2 made the front engine the 2 axle one and put
> the three-axle second engine the right way
> forward.
>
> The Q2s were an attempt to improve upon the J1
> 2-10-4s but they were only marginally better, even
> when they weren't slip-sliding away.
>
> It would have been interesting to see what the
> Pennsy would have come up with if they had built
> R2 class 4-8-4s instead of the exotic T1s.

Really interesting. Never was a Pennsy fan but it seems they were at the forefront of steam engine R&D.

Did the T-1 really have a max speed of 140? Cause if that’s true that would make them the fastest steam engine in the world.