4-8-4 comparisons

I don't have a final answer, but they are probably all capable of pulling our train and I would think that on flat track the big drivered engines would ultimately reach the highest speed, so I think 3751, 4449, 844 and 700 would be the leaders on flat track. On the grade its really hard to say. 614 & 2100 might be able to pull more weight up a grade (especially if they still have boosters) but that comes at least partially at the cost of speed and I don't know if a 15 car passenger train is heavy enough to give them a speed advantage over the faster engines. They might all be really close. Knowing the actual top speeds of these locomotives might help, but I don't know where to get that info. It might also make a difference if the locomotive can get a run at the grade and get over the top without having to stop, or if it has to start the train from a stop on the grade. 614 & 2100 would probably have an easier time of starting and accelerating with a train on the hill. SP&S 700 seems to fall in between as far driver size goes with about the same tractive effort as the others; it wouldn't be either the fastest or the strongest, but with a passenger train on a grade, maybe its middle ground would give it the edge.

I don't know the top speeds of the other locomotives mentioned, but the C&O 614 is all roller bearing construction, with a highly balanced drive train. It has a top speed of 120 MPH!

Ross Roland damaged the Franklin HIgh Speed Booster during the ACE tests in the 1980's. It was removed to be repaired, but Ross decided not to reinstall it at the time to cut down on maintenance costs. A booster is really not needed anyway for relatively light weight passenger excursion service, where a locomotive would depend a high speed power most of the time. According to official C&O documents, the booster provided 15,000 lbs extra tractive effort up to 30MPH. The C&O rated the 614 at a total of 83,300 lbs TE with the booster in place.

Of the locomotives mentioned in the above post, the C&O 614 has by far the most powerful boiler. In fact, the 614 has an absolutely enormous boiler for a 4-8-4 with nearly 5,600 sq.ft. of evaporative heating surface, and an additional 2,300 sq. ft. of superheater surface. Not surprising considering the C&O 614 boiler is based off the huge C&O Class T1 2-10-4's boiler. The bigger the boiler, the more power at speed! The C&O 614 is the definition of SuperPower

While I share steamfan1945's enthusiasm for the 614, I also realize the need to be dispassionate in a discussion about steam locomotive technology.

In this case, I figured that the best way to answer the 614-booster question was to go right to the source. This morning I received a response to my query from Mr. Ross Rowland.

Apparently the main bull gear of the booster (similar to a diesel, this is the large gear mounted to the axle) had some metal fatigue issues because they busted a few teeth off the gear during the 614t tests. During preparation for the 1998 NJT excursions to Port Jervis, it was decided that she had sufficient power to pull the train over the terrain without the booster.

They are hoping to make the repairs during the woprk to bring her up to FRA code for the Yellow Ribbon.

What about the former Mexican FEC 4-8-4 that's out back of NH&I?
I realize that it's curently undergoing restoration, but I belive the goal is to get it running again.
I noticed it seems a conciderably smaller size than it's US cousins.
Does anyone know what it's capabilities are for pulling coaches?