"Most powerful" LV Steam locomotive class.

[scottychaos]

I have always naturally assumed it would be the 4-8-4 Wyomings..
but im comparing stats of the LV 2-10-2's compared to the 4-8-4's.

2-10-2 data:
Engine Weight 370,000 lbs
Tractive Effort 72,620 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.98
http://www.steamlocomotive.com/santafe/?page=lv" onclick="window.open(this.href);return false;

T2 class 4-8-4 data:
Engine Weight 451,000 lbs
Tractive Effort 66,982 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.10
http://www.steamlocomotive.com/northern/?page=lv" onclick="window.open(this.href);return false;
The 4-8-4's also have "power computation" data at the bottom of that page.

The 4-8-4 is heavier, but the 2-10-2 has a higher tractive effort.
Im sure there is more to "most powerful" than just the tractive effort alone,
but based on that one number alone, it seems the 2-10-2 is "more powerful" than the 4-8-4,
although I doubt this is actually the case..

It seems unlikely that a 1917 locomotive would more powerful than a 1932 4-8-4,
so im assuming the 4-8-4 is actually "more powerful" in reality..but I dont fully understand what the numbers mean..
can anyone clarify?

thanks,
Scot

[poppyl]

Scot;

Might your answer lie in the driver diameters and cyclinder lengths? Can't speak to the LV, but the Western Maryland's I-2 Decapods (not the Russians) had a higher TE rating than their Potomacs. I have been told that the smaller drivers coupled with a shorter stroke gave them more TE at the low end than the Potomacs, but that the Potomacs excelled at the higher end.

Poppyl

[lvrr325]

Steam locomotives were more purpose-built than diesels. The 2-10-2 could haul heavy coal drags out of the mountains, but likely was incapable of the same top speed as the 4-8-4 with it's larger drivers.

But note the last number is higher for the 4-8-4, so despite a lower T.E. and one fewer pair of drivers it has a higher abilty to apply that effort to the rail.

[scottychaos]

Thanks guys..
I dont think speed is a factor when considering "most powerful"..
so the fact that the T-class was faster isnt really relevant IMO..
when considering "most powerful", for me, im just considering "how much tonnage can it haul"..
Scot

[poppyl]

Scot;

I think that the answer to your question lies in calculating/plotting the drawbar horsepower curve for each locomotive across a speed range. The drawbar HP curve is derived by multiplying drawbar pull (in pounds) by speed (in MPH) and then dividing the product by 375. I haven't had the time to see if the curves for your specific locos are available on the web, but there are a bunch of 4-8-4 curves out there. Not so sure about 2-10-0's, however.

Poppyl