by diburning
Is the prime mover the issue here? I always thought it was the HEP. Metra operates long trains (9-10 cars) with all flavors of F40s all the time. Unless those gallery cars are a lot lighter than the MBTA's coaches, the F40s should be able to handle longer trains just fine if they can provide the HEP. But, Metra averages 30-35mph between stops on local trains, so that might be the real difference.