Problem with enginespecs

nicola86

Active member
Hi; I'm having a problem with some "enginespecs" of as many locomotives, in particular those of the SD70M/MAC, SD9043MAC, C40-8/W and occasionally also of the SD70Ace: the problem is that using them with heavy trains on lines with very demanding climbs (such as the Donner Pass of Jango) they tend to slip too frequently once they reach 20-15mph, which did not happen with the old engines with kuid :1.

Can you suggest a solution? Should I delete the new enginespecs and go back to the old ones?
 
Hi; I'm having a problem with some "enginespecs" of as many locomotives, in particular those of the SD70M/MAC, SD9043MAC, C40-8/W and occasionally also of the SD70Ace: the problem is that using them with heavy trains on lines with very demanding climbs (such as the Donner Pass of Jango) they tend to slip too frequently once they reach 20-15mph, which did not happen with the old engines with kuid :1.

Can you suggest a solution? Should I delete the new enginespecs and go back to the old ones?
There is no need to edit config.txt files to update or change your engine specs.
In the session editor, CTRL+right-click on the locomotive to open the properties panel.
Click on enable editing.
You will see the engine specs used and you can choose another.

In real life, Donner Pass is extremely steep and requires multiple diesels to pull the long freights over the Continental Divide.
 
Nah i have to disagree, he is right here. Tractive effort is just weird in trainz, has nothing to do with what spec you use or how many engines. No matter what, ~ 150k lbf seems to be the practical maximum the sim allows to be applied to the rails on a 6 axle engine.

I tried changing and editing that a few times, especially for SD70ACEs that are used on 0.6/0.7 HPT (Horespower per ton) 20.000t coal drags that DO creep up hills like that at 10-15mph. In trainz, once you get low speed enough to get over that ~ 150klbf limit in N8 or N7 (About 12mph) - the wheels immediately slip and Tractive effort reduces to about 33k lbf instantly. You then have to reduce 3-5 Notches (not just one!) to stop them from slipping, then increase back to N6 below 150k lbf to keep going at all. Else you come to a stop pretty quickly, cause what is ~ 33k lbf on a steep incline?

Completely ridiculous from real world experience. Not even in rain does TE reduce THAT much, yes the wheels will occasionally slip and overspeed, but a.) can that be remedied by applying a bit of independent brake to arrest them, and b.) does Sand have an immediate effect to stop it or at least increase your TE back up to a reasonable amount.

Which it doesn't in trainz, like at all!

You will still have to reduce your power to near 0 and then increase it up again to stop the slip, even with Sanders active. I've been driving real freight trains half my life at this point, and this is just completely wrong - and sure enough will stall your heavy train on a grade, even if your HPT is more than enough and it never would in real life. Maybe if some TM Ground relays trip, but not due to slip or tractive effort in itself

I have to say however, this doesn't seem to be a JR problem, and i've always had problems like that in trainz with any heavy train & in any version from TS12. It's a hard coded, N3V game engine/physics related issue IMO

Oh and lets also not forget the ear splitting and extremely annoying wheel slip sound straight out of idk, UTC? That is still used 😂
 
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Guys, everything is fine with physics in Trainz. It's just that those who write traction do not want/cannot thoroughly understand the issue. And this issue is not as simple as it may seem at first glance. Or they are not interested in it. And if all the components of the traction/resistance process are set correctly, everything will go as per books and graphs. And the more accurately all the components are set, the closer to the desired result will be. And not only will it be, but it has been going as it should for a long time.

PS: google translation.
 
@flusi737 Could you explain better what you wrote, perhaps via PM?
In summary, Trainz engine physics is crap since at least TS12.

You could try modifying your own using the Test Track if that's still available. I can't remember if it's still part of TRS19 and the TRS22 products. The last time I saw it was in T:ANE and it was still unfinished.
 
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