Pulling Power of a Williams GP9 Diesel

[peisenmetrains]

Can anyone give me a rough estimate of how many cars (standard O gauge) that a Williams GP9 can comfortably handle?

Also, at what consist size would you add a 2nd powered unit?

Finally, would a second powered unit allow you to run the consist at a lower speed?

Thanks much. Pau

[Len]

We've pulled up to six 18in lighted passenger cars or 12 freight cars on a regular basis with no probrlems using a Williams GP-9 on the shopping center display layout outside of Tom's Train Station in Raleigh, NC. It may handle more, but any more cars than that, and it looks like a dog chasing it's tail.

Len

[phillyreading]

I have used my GP-9 with about 15 quad hoppers and a caboose on 042 curved tracks. Also noticed that the Williams GP-9 pulls more than the Williams SD-45 at the same voltage output from a postwar ZW.
To pull more than 25 cars with two or more engines requires having a good size layout, most of the time, more than an 8' by 8'. Another thing to do is to put one powered engine in the front and one powered engine in the rear of the train, as this keeps down derailments.

Lee F.