RPM Stealth Gearbox Conversion for a Brushless Buggy?

[drbelleville]

Guys, was wondering if swapping to a RPM Gearbox from a standard stealth tranny would help as far as running a brushless setup in an Old RC10 Graphite. I am just looking to add a bit more reliability - not that the stealth is weak. This is a buggy of a Family members that has been sitting in his Garage collecting rust and dust! The bearings in the stealth are all seized as are the Wheel and Hub bearings So he asked if I could help him out, and revive the car - although preferrably brushless and Lipo capable. I am thinking 17-22 T Brushless as of right now.

If there is a topic already, please point me in the right direction, and then the mods can delete this.

Thanks,
Maurice

[adam lancia]

The only difference between the two transmissions is the top shaft. Stick a B4 top shaft in the Stealth and have at it. It'll handle down to an 8.5 without sweating.

[drbelleville]

Thanks for the info. I think I may have him get one to retrofit.

Maurice

[Charlie don't surf]

Well, the gear ratio is different as a result of the topshaft as well, the 2.65 internal ratio of the RPM tranny also is a little quicker to spool, keeping the temps down. But I have run both with a 6.5 on a super bite track and other than the spur/pinion ratio they both work well ( I prefer the RPM ) the B4 slipper is easier to adapt to the 2.25 stealth ( top shaft/plates pads/spring & nut )
and is the only weak spot in the 2.25 or the RPM with the stock slipper-

[drbelleville]

Well, the gear ratio is different as a result of the topshaft as well, the 2.65 internal ratio of the RPM tranny also is a little quicker to spool, keeping the temps down. But I have run both with a 6.5 on a super bite track and other than the spur/pinion ratio they both work well ( I prefer the RPM ) the B4 slipper is easier to adapt to the 2.25 stealth ( top shaft/plates pads/spring & nut )
and is the only weak spot in the 2.25 or the RPM with the stock slipper-

I was thinking that with the newer more powerful Brushless motors and 2.2 tires, it would seem like a logical choice. And a better bottom end is always a good thing as well.

[adam lancia]

Brushless motors make tons more torque than brushed motors, unless you'll be running a 3.5 or something like that, a lower numerical transmission ratio will be more desirable. As it is already, guys running 17.5's in B4's are running 68 tooth spurs and 38 tooth pinions to get a decent gear ratio as the motors love to pull tons of gear. I would stick with the Stealth and use a B4 top shaft but that's just because I don't have any 38 tooth pinions

[aeiou]

I've been running my old/new buggy with the RPM trans and the T3 slipper using a Mamba Max 7700 brushless setup for about 2 years now. I've had no issues with the transmission/slipper at all, and I haven't been gentle with it either. In fact, I recently tore it down for maintenance for the first time since building it and I was surprised at how little wear and tear there was in the gearbox.

I'd think either transmission would work just fine with at least the T3 slipper installed.

[scr8p]

As it is already, guys running 17.5's in B4's are running 68 tooth spurs and 38 tooth pinions to get a decent gear ratio as the motors love to pull tons of gear.

precisely the reason there's a 1.96 rpm trans in my v-nats car (17.5).

[drbelleville]

Thank you everyone for your help and input.

[JK Racing]

I have a 17.5 hooked up to my 6 gear tranny right now. I could use a touch more top end, but it is geared "conservatively" @ 26/81. I have a 78 I am going to drop in and do some runs (in the street) next to my boys T4 for a gauge on top end.

[drbelleville]

Alright, so I am getting close to putting the tranny together, and man I had forgotten how heavy the outdrives were. I was curious were there even any lighter ones offered (Delrin or Aluminum). I had found some on Custom Works site and wondered will these work?

They are PN# 4381

http://www.customworksrc.com/ProductDetail.jsp?LISTID=80000764-1255375629

Thank you everyone for your help,
Maurice

Some pics of the buggy - and its progress.

[scr8p]

i'm pretty sure those cw hubs are for the 2.40, maybe 2.60. either way, they won't help you out.

no one makes lightened 2.25 outdrives anymore. factory works, mip, barracuda, irs, hg all did back in the day.

[drbelleville]

Thanks, I guess I will do some Lightening myself then.

Maurice

[Mr. ED]

Aren't those delrin cups the 'real racers' choice hubs = they'd give you that extra edge but you had to sponsored so you could afford to replace them every other race
Only good for shelfers these days

[drbelleville]

+1

I am just going to Machine the stock ones a bit, and maybe open the drive slot so I can add blades to the MIP CVDs.

Oh well I should not be so worried - its not mine, but I am building it like mine, lol.