[Loneranger840]

I have an Arcornite 19t motor, I adjusted the timing to 20 degrees ( this is what the Pro version is set at ), what kind of life can expect out of the brushes & comm?

[highroller]

For serious racing in oval where those are legal, the timing is set a 24 degrees on flat or short banked tracks, 36 degree for large banked ovals.
For bashing 18-24 degrees should be ideal, less timing degrees the rpm - acceleration some but lengthens runtime and reduces wear. To gain back a little of the acceleration increase the pinion by one tooth.

There were two Arconite versions, one was legal had normal size standup brushes and 2 magnets, the one with P94 size brushes and split magnets weren't legal for organized racing but can be used in bashing. The only difference in power between the two the standup brush produced more rpm while the P94 split magnet made less rpm, slightly more torque.

[Loneranger840]

Well, I noticed when I had it set at 0 degrees, my runtimes were shorter, now hat its set at 20, my runtimes are longer and rpms seems to go way up. It still has plenty of torque for my needs. I just don't want to blow though a set of brush every other day and ruin the comm.

[highroller]

The best way of limiting wear is find the right brush, spring tension and timing. Using a brush with less silver content should reduce some of the comm wear, right spring tension keeps brush from bouncing when motor reaches it operating levels (at high revs the spring may not provide enough tension), timing can affect what the spring tension may have to be, lighter brush like Red +, Green - may be okay for timing in the 12-20 degree area then from 2 reds to purple/red at maxium level or 36 degrees.