RC10T Brushless Conversion Results

[Ace4]

Summary
So a few weeks back I was digging in the garage and came across my RC10T from 20 years ago. I put the NiCd pack on my charger and it surprisingly took a charge. I put new batteries in the AM transmitter, plugged in the battery pack, and amazingly everything still worked. I drove it around some dirt lots nearby, and it was a lot of fun. The NiCd pack only gave about 3 minutes runtime, though. This led me to thinking "hey, it should be pretty easy to convert this to a brushless lipo setup". So $60 for two lipo packs, and $60 for a Turnigy ESC and Hobbywing motor later (and 2 weeks to get it from HK), my RC10T has been reborn. I also replaced the S148 steering servo with a digital that I had sitting around from an old helicopter.

Before
Apparently I put some effort into this truck 20 years ago, it had a 7 cell NiCd 1200mAh pack, a modified Reedy brushed motor, and a Novak ESC mounted on a nice carbonfiber mount. The slipper was replaced with something else, I think it was a Losi "hydradrive" or something similar sounding. I have no idea what pinion and spur the truck has, and I'm too lazy to count the number of teeth. All of the kit bushings had been replaced with bearings, and MIP CVDs replaced the original dogbones. I don't think the tires are original, since I found a bag with some very worn out tires. I was surprised to see that it was using what looked like Anderson Powerpoles, I didn't realize they had been around for 20 years.

So the truck still drove, and it was a lot of fun tearing around dirt lots near my house. I'm not sure how fast it went, I would have to gestimate around 20 mph. Since the NiCd was likely in sad shape, runtimes were around 3 minutes tops. This would not suffice.

New Parts
Turnigy Trackstar 60A ESC w/ programming card ($29.59)
EZ-Run Brushless motor 3900kV 10T ($29.46)
Gens Ace 2s 5000mAh 40C hardcase battery packs ($29.95) (x2)
Futaba S9350 digital servo (free, had laying around)
XT60 connectors (free, had laying around)
Velcro straps (free, had laying around)

The Conversion
It was stupidly simple. I don't know what else to say. The motor bolted right on, the pinion bolted right on. I attached the ESC with double-sided tape. The servo bolted right in place of the old servo. The biggest issue was the fact that I quickly learned that 5000mAh packs WILL NOT fit. They are too tall to fit into the RC10T rear battery mount. I was faced with the dilemma of cutting the top of it off to fit it in, or being creative. I decided to be creative, since I didn't want to cut up original parts. Hence the mess of velcro straps to hold the pack down (just run through the rear servo mount screw), and another strap to keep it from sliding forward.

Results
After plugging everything in, I was nervous. I didn't know if the transmission or slipper would smoke on first use. Using the ESC programming card, I set it to "normal" acceleration. Since it had been raining for the past two days, and also since it was dark outside, I just decided to run it on the road in front of my house. WOW. It was way faster than before. Obviously I didn't put any effort into measuring real top speed, but I would say it was higher than 30 mph. I arrive at this conclusion by comparing my judgement of speed to the used Thunder Tiger Sparrowhawk XXT that I just got, which some reviews said is around 30 mph on 2s. It was a blast with the newfound levels of power and speed, however something that small VERY quickly becomes invisible at those speeds when it's dark outside, so I was very limited in my testing. I drove it around for about 5 minutes to make sure nothing exploded or started on fire. The battery still was at 3.95V per cell after using it for this and about 3 minutes of running the Sparrowhawk XXT. So runtimes even on a smaller pack would be great.

Caveats
I'm worried about the slipper. I changed the ESC acceleration setting to "low" now, since if I jammed the throttle I could hear the motor spinning hard for a moment until the truck got moving. I don't know what the slipper can take, or what condition the fluid in it is in. I also don't know the gearing on mine, so keep that in mind if you try this on your RC10T. If you decide to do this, I would recommend going with a smaller lipo pack, something that isn't quite as tall as a 5000mAh, so you can fit it into the rear battery mount.

Future
I'll post some updates at some point in the future when I get a chance to run the truck at a local track (I have to find one first).

[JOESGARAGE]

I have a castle creations in my RC10T with no problems.....super fast and smooth....you'll love it!

[littleVETTE]

that's a real nice truck. love the work you put into it. those cvd's you got in the rear are aluminum. check on your diff, and see the condition it's in. maybe it's loose? if not check the slipper clutch. you might have it loose. take the 4-40 locknut off and slip off the hydrive drive unit, and take off the slipper pad. it might of been glazed from all the slipping. if it is give it a lite rub on a scotch brite pad, to clean off the glazing. or you could use an exacto knife, if you don't have the scotch brite pad.

if i were you, i would just take the tranny out of the truck and rebuild the diff. if you think the hydra drive is giving you trouble, you should put the old slipper clutch back on. assuming that you still have the shaft and the outter hub assembly. or if you want to upgrade, buy a b4/t4 shaft and the accompanying slipper assembly.

if you don't have the instructions on the hydra drive i'll send them over to you. just in case you break it down.

[teman]

I'm pretty sure you could modify a nice B4 battery strap to work... it looks like this:

9638_md.jpg (33.72 KiB) Viewed 5535 times

9638_md.jpg (33.72 KiB) Viewed 5535 times

[Crazydeath]

Wow Ace4 that's realy cool. I can not wait to convert my rc10t.