Tier 4 Speeds


Get over it
I have 6 Metra Nippon Sharyo Coaches coupled to the Demo loco, all signals are green and the speed limit is 70mph but the fastest the consist will go is 64 mph. I even attached a second Tier 4 to the consist and it still only goes 64 mph. Why? Is it a built in safety factor? Thoughts or suggestions. Thanks.

Now that I have seen the thread over here....

What readout are you using to measure the speed? Cab view, external, or the digital readout on the HUD?

What version of Trainz are you using?

I ask because there seems to be a bit of disparity in speed measurements between the 3 that I have been recently been made aware of.
there appear to be enough threads and posts on the issue I'm thinking now.

Change the espec over to something else??
Chris - I'm running TS12 with no patches. I'm getting the same readout with cab view, external view and HUD view. I went into the config file and upgraded the enginespec (2:473973:100597:1). Hope that was OK. If I drive manually I can get it up to 72 mph. It's only when the AI is in control that it goes 64 mph.

Lucy_Hale - you might want to register your game before you go any farther. I always run in Realistic mode and I don't think that makes a difference.

H222 - I like to try to give the authors a chance to be aware of a problem and see if they can fix it. That way everyone wins. If it can't be fixed for whatever reason than I will start looking for a substitute. Do you have an enginespec in mind?
I will have to look into this..
cab control is 70, but AI is 65..

Once I get it figured out I will issue an upgrade
Chris - upgraded to the newer version on my computer, from 473973:100597 to 2:473973:100597:1. Seems like all the reskins have the older version in their config file. I tested it with both versions and the results were the same. Weird huh? Thanks for looking into this. One quick question, in the enginespec file I see where it reads something about maximum speed is 33. 33 what?
The "33" in the config "maxspeed" tag indicates the maximum speed of the loco in DCC/AI mode, in meters per second. 33 m/s = 73.819 MPH

I made a couple tests, one in manual DCC mode (the figure in red is a "74")


And one in IA mode:


In both cases, the ES44AC Tier 4 attained 74 MPH

In cab mode, the throttle-power container lists, for notch 8, tractive effort values equal to:

90.9 kN (20,435 lbf) @ 29.6 m/s (66.213 MPH)
0 kN (0 lbf) @ 31.3 m/s (70.016 MPH)

In the cab mode test, I managed to attain 69 MPH (the HUD speed indication is not as accurate as the one provided by instruments, as it uses an "averaged" speed: it can differ by 1-2 MPH from the actual train speed).

The test was performed on the Sherman Hill, on a 1.3% climb just west of Cheyenne, so it is possible the locomotive may indeed reach 70 MPH on a flat straight track. At that speed, however, it will be uncapable to move anything but itself for lack of tractive effort.

Note for Chris: I do not know the U.S. practices for locomotive testing: here in Italy, acceptance tests for locomotives and rolling stock include testing at 110% of their rated maximum speed (e.g. a 200 kph (125 MPH) locomotive is tested at 220 Kph (137.5 MPH)). This implies the locomotive must be able to reach at least 110% of its rated maximum speed.

Trainz Engine Editor is a fine tool, but it automatically sets the tractive effort to zero at the maximum speed you enter in the dialog box. As a consequence, the locomotive will never be able to reach that speed because it has no tractive effort. I usually specify a maximum speed value equal to 115% of the maximum rated speed, so that the locomotive has enough residual tractive effort to haul something at its maximum rated speed.

Thanks for replying Carlo. I always run in DCC mode and running manually I also got to 72 mph. The problem occurs when the AI takes over. I hope Chris understands your input and can fix this .. Thanks.
Thanks for replying Carlo. I always run in DCC mode and running manually I also got to 72 mph. The problem occurs when the AI takes over. I hope Chris understands your input and can fix this .. Thanks.

In my IA mode test the locomotive - running light - attained 74 MPH (with a 100 MPH speed limit) and it had to travel almost 5 full baseboards (approx. 2 1/4 miles) to reach that speed. I have also noticed that sometimes the AI will drive a few MPH slower than the speed limit. What speed limit were you using?

Change the engine spec speed from KPH to MPH will fix the problem.

Speeds in the enginespec are (and must be) expressed in metres per second, not in KPH. In Chris' enginespec, the values for DCC are perfectly accurate; only the throttle-power section needs some fine-tuning.
Carlo, I have 70 mph speed signs placed along the tracks. If I understand what you're saying is if I place 75 or 80 mph signs I may reach 70 mph. I will go check it out now. Be back shortly.
Carlo, changed my speed signs to 75 mph and I got the loco up to 68 mph which is 4 mph faster than before. I'm going to assume that if I changed the speed signs to 80 mph I will get to 72 mph which confirms what you stated in post #13 about the AI running a few mph slower. If Chris can't fix this or it may be more work than it's worth at least I have an option. Thanks again for your input.
I have changed all of the installed maxspeed engine.spec speeds from 33 to 70 and do not have a problem with locomotives attaining that speed, 70 MPH. I drive in AI/DCC mode.

@ John:

I would be surprised if you had problems keeping line speed with such a ES44 dragster :D.

This issue with AI driving seems to occur when track speed is equal to the locomotive max. rated speed. Some time ago I had similar issues with a 200 kph (125 MPH or 55.55 mps) locomotive travelling on a line with a 200 kph limit: it ran at 196-197 kph in AI mode. Setting the max-speed tag to the equivalent of 220 kph (61.11 mps) solved the issue.
To all who have replied. Thank you. I hope that Chris hasn't spent a lot of effort on this because now it seems to be working correctly. The only change I made was to update the enginespec in the config file as I stated in post #5. Replaced my speed signs back to 70 mph and that is the speed that I can attain now. Weird huh? I have no idea why everything is okay now. I know that I'm not crazy because I did check everything out before I started this thread. Anyway, thanks again for all your efforts.
alrighty, it looks like this has been resolved then.

Pendolino, thanks for the heads up on the max speed, I will have to try that.