I included the locos to give you an idea how the e-spec will handle, allot of people don't know this however the anim-dist on the driver bogie can change how the loco produces power, smaller wheels increase power while larger wheels decrease power
for example in real life 18x26in cylinders with 4ft6in wheels at 112 PSI is 17,400blf while 5ft0in wheels is 14,025lbf and 6ft0in wheels is about 12,600lbf.... trainz also models this, if you open the e-spec I gave you and see the notepad (data) it has the cylinder volume calculations, all steam physics I've released from 2016 to now use this method, trainz also has a script code called "get-max-tractive-effort" and tells you the tractive effort at the low pressure safetyvalve setting, I set it to the running pressure, so 140PSI / 80% WP = 112PSI so I adjust the bore until it matches, I never change the stroke, this will cause issues if the stroke is too long or too short, too long causes excessive wheelspin and too short the loco pretty much sticks to the rails like Billegulla's spread sheet specs as he adjusts the stroke rather then letting the anim-dist do that.
Cheers.
