Russo Loco Wrote:
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> My mistake, Earl -
>
> I mis-remembered you stating on an earlier thread
> that the K-37's could pull more but
> were a bit slower than the K-36's, and attributed
> it to a difference in boiler horsepower
> since the K-37 boilers are an older design by what
> - roughly twenty years?
>
> - Russ
The extra Tractive effort is pretty much eliminated by the extra weight the 490's carry around in the way of a bit more coal, 1000 more gallons of water and some extra heft in the engine itself. When figuring the tonnage rating for an engine, the first thing you subtract is the TE required move the engine itself, then you add the train.
490's carry enough extra weight in the drivers to give them a little more adhesion to get one more loaded car up the hill (20 tons), but it goes that much slower. One thing that big firebox is good for is making steam. You could beat 497 on the back all day and not run out of steam or water.
Enough! Back to the Garratts!!!