NSW 620/100/400 power problem

[nathanoregan]

Hi all.
I've been using the 620/720 set from Coals to Newcastle on their test route (620/720 here, Test route here), and the 620/720 appear to have a speed limit of about 1.5MPH. Looking at the shift+F5 menu for loco information, it appears that at that speed, there is no more force being applied. If someone could possibly replicate this, or tell me what to do to fix this, that would be excellent!
I would test it in MSTS, but I don't have it, having been playing almost exclusively Trainz until I discovered Openrails.
Thanks.

[Armchair_Engo]

I've had a fiddle with a NSWGR 400 class since that is what I have installed.
I suspect that the changes I will list can apply in principle to the later larger classes.
As ORTS evolves the coding, it may change the required numbers. Diesel hydraulic operation is probably not a top priority.
I am currently running X3095 (stable rel).

Copy and paste back to the same folder the 400-FPH.ENG file, rename it to 400-FPH.ENG.ORIG or something like that so if you mess up the edited file you can recover.

Working with 400-FPH.ENG :

Change Mass( 28t ) to Mass ( 40t ).
28t seems a bit light for something that ended up with twin GM 6-71 diesels, somewhat like the Victorian Railways DERM which were about 40t.
Edit Add: if you change the Mass(), also change the DerailRailForce ( 2.5*28t ) to DerailRailForce ( 2.5*40t )

Change MaxPower ( 246kW ) to MaxPower ( 220kW ) . Wiki lists the engines (petrol or diesel) as 110kW each.

Change out the Gearbox lines. I have left in the comments to show what I have changed. I could not find a reference that listed the max tractive effort so what is there will do for now.

        GearBoxNumberOfGears( 1 )
	GearBoxDirectDriveGear( 1 )
	GearBoxMaxSpeedForGears( 60mph 60mph ) Comment ( was 1 70 )
	GearBoxMaxTractiveForceForGears( 35kN ) Comment (was 27007N )
	GearBoxOverspeedPercentageForFailure( 170 )
	GearBoxBackLoadForce( 4500 )
	GearBoxCoastingForce( 2000 )
	GearBoxUpGearProportion( 1 ) Comment ( was 0.85 )
	GearBoxDownGearProportion( 1 ) Comment ( was 0.35 )
	GearBoxOperation( automatic )
	GearBoxEngineBraking( direct_drive )

Have a fiddle and see if you get something better.
The alternative is to reconfigure those railcars as diesel electrics and make up some numbers that approximate the performance of the prototype.

The brakes could use a bit of work as well.
MaxBrakeForce( 140kN ) seems rather excessive for something even at 40t. Try 60kN and find something that feels right.

For some quicker response from the brake lever, change Brake_Train ( 0 1 0.0125 0.75 to Brake_Train ( 0 1 0.025 0.75

[nathanoregan]

That's much better!
But...
I still only get a top speed on a level of 38.9MPH with no load.
This can't be right, can it?

[Armchair_Engo]

Then try GearBoxMaxSpeedForGears( 50 ) . Use whatever works for you.