JAG Racing

This is the stock diff gear set... I thought you found a light-weight aluminum version of this somewhere... sorry, my misunderstanding.

HarKonnenD

iTrader: (23)

Ohh no. I just heard from an HPI guy that a 4gear diff in the rear offers more stable traction under accelerating.

AMGRacer

The 4 gear diff binds up more when torque is applied to the diff. So it basically increases the stiffness of the diff compared with the 2 gear diff given the same diff oil weight.

KLANDERMAN

THANKS EVERYONE!!!
I got 3rd place on the first hit, then on the second hit I got 1st. place, on the 3rd hit I had problems with the steering, aparently there are 2 nuts, one on each side that tend to get stuck an I couldn;t get my car to turn left, but in the end I got second place overall and that was good enough for me.... Thaks everyone for all your help...

One question. I run on pavement and I'm using still the stock tires for my R40. What kind of tires should I use foam or rubber? I ordered some ellegi racing 35s, but I dont kow if rubber works better on pave?

JAG Racing

Typically rubber works on concrete and foam works on asphault. You might buy some 35/37/40 combinations to help tune your car better.

KLANDERMAN

I'll do that...
I was reading about the 4 gear case for the traction, but got confused, is the one mentioned a stock one, or is this an optional part for the R40? I've seen the one mentioned at towerhobbies, ut it looks stock. The one I want is aluminum and its at r/c mart, if you wanna check it out i'll send you the link.

JAG Racing

The Tower one is the stock differential gear set. Please paste the link when you have time - THanks.

KLANDERMAN

http://www.rcmart.com/catalog/produc...oducts_id=7253

If the above link doesn't work, try this...

The home page is www.rcmart.com , go to parts, select Gp, then pick the HPI r-40 and select the brand three racing, they have many optional parts here... the rear casing is on the second page... good luck!

KLANDERMAN

When I was putting together my R-40 I saw the option to put a 23T or a 22T on the large belt. What does this do? Whichone is better?

JAG Racing

The front wheels and rear wheels rotate at slightly different speeds. Typically most 4WD cars have the front wheels turning lsoghtly faster than the rears.

Changing the pulley gears on the large belt allows you to change the amount of front wheel overdrive. This is something that I will be experimenting with as well. Since you have two gears 22/23T(front shaft) and 18/19T on the rear shaft, you can experiment by changing these around to different configurations.

Keeping in mind that a smaller diameter gear provides "increased rotation speed" compared to a larger diameter gear you can experiment. Let me know how you like it.

KLANDERMAN

Actually thats how I've benn using it, It handles well, but I still have to try it with the 22 T to see what changes...
Did you check out th aluminum casing?

Rapid Roy

An aluminum dif case and gear will probably add quite a bit of rotating mass. The picture also doesn't show the internal side so I'm not sure if it will accept the 4 gear conversion. Reducing rotating mass is half of the purpose of the .8 pitch 2 speed, so adding weight to the rear diff probably wouldn't be your best choice. Are you having problems with the stock case and gear?

KLANDERMAN

Well mostly with rocks and debri, they get stuck in there and disfigure the casing, making it imposible for the belt to be tight. That's basically the reason why I went ahead and ordered the aluminum, but the one I ordered is for the front. Let's hope I don't regret it later...

KLANDERMAN

Has anyone used the Trinity wasp engine? It's a big block .12 turbo.

goldenboy

speakin about belts being tight....has anyone seen those orange looking fiber belts, ive seen them on g4's, i was just wondering if anyone makes them for the r40, cuz mine stretch really easily and come off, especially the side belt

thanks