Project: Prop Car

Version 1.0

The platform for this version was a regular RC10B3.
I simply zip tied the vertical component of a motor test stand to the rear shock tower, removed the tranny, placed Losi axles (minus universals) in the rear hubs, and bolted front tires on the back.
Performance was wimpy, run time was short, and motor wear was pretty bad. It was also very top heavy and handled poorly because of this. Rolls were common and typically catastrophic (broken motor mounts, snapped props, etc)
I used motors ranging from 12-16 turns. The Reedy Sonic line of motors seemed to work best.
The prop pictured is a three blade pusher style with a 5x3.5 pitch

Version 2.0

I got rather serious with this version. The main goal was to improve stability, hence the super wide rear arms. I used the front end of an old RC10 Worlds Car and the chassis of a very old RC10 Graphite. The rear end is quite the hodge podge and includes: Losi XXT rear arms, Losi shocks, RC10 Worlds Car inner suspension mounts, RC10 B3 hub carriers, and RC10 GT rear bulkheads (two of them). All this stuff fit together amazingly enough, but did require "custom fitment" using an exacto knife :) The drive components remained basically the same as version 1.0, but I did start experimenting with props. It became clear pretty quickly that prop selection was very important. The only problem was finding pusher props. Handling with this version was much, much improved. Rolls were not even possible. It would slide out before rolling on any surface type. Because of improved handling, top speed was improved and because of prop selection, acceleration was now much better.

Version 2.1

Brushless!
This was THE big improvement. Run time tripled (at least), performance was increased dramatically, and no motor wear. The motor is an Aveox 1409/3Y. This motor can swing some pretty big props. Bigger than will fit on the car, in fact. I had to start all over with prop selection, but two things massively helped in this regard: 1) Aveox has had a "virtual test stand" on their website [link removed as Aveox does not appear to be in the RC business any longer] for prop selection, and 2) I finally figured out that pusher props were not required (DUH!). Reverse the prop and reverse the motor direction. A slight modification to the prop hole is required for most props. The wood prop shown did not last long. When the prop is swinging away only a few millimeters from the ground, it tend to strike rocks, etc. I think it actually sucks them up! The wind force is almost scary.
One important aspect of this motor/controller combo is the number of cells that must be run. If you look close, you will count 10 cells. That is a lot of weight...

Version 2.2

These two pics were taken haphazardly. I did not even have the receiver pack in, nor was the controller mounted .
Hopefully I will get some better shots up soon.
The main difference with this version is cell size and count. 12 cells! Amazingly, these 12 cells weigh less than the 10 cells in version 3.0 weighed. This is because they are 4/5 Sub C cells. Instead of a 2400 Mah capacity, they have a 1700 Mah capacity.
The final prop choice is 7x8 (!). I must have bought 20 props during this project. Good thing they are cheap.

Version 2.3

The two biggest changes in version 3.2 are a LiPoly pack and foam tires.
The LiPoly pack made a huge difference to acceleration because the battery pack now weighs less than half. The pack in version 3.1was 590 grams and the 14.8v 2600 mah LiPoly pack is only 255 grams.
The same could be said for the foam tires. They weigh less than half, have more consistent traction, and lower the CG of the car (by virtue of being smaller in diameter). Looks pretty good with that body on there, eh?