Granite Arrma 4x4 Granite BLX 3S best pinion tooth size for speed

[nObZ]

Just getting into the Arrma brand, use to be into Traxxas but I have moved on we can say... I currently have the arrma granite BLX and I am overwhelmed with the optional pinion gears that arrma provides. My question is what pinion size should I run to give it more speed without having to check the motor temperatures constantly. I believe the stock pinion is a 14t or 15t and I was thinking about putting the 20t as I feel like the 26t would be overkill on the motor. I am leaning towards the 20t as the Vortek's optional gear is the 20t and has the same ESC and motor combo and it goes 60mph+. My goal is to be in the 60mph+ area as I want it to be faster but not too fast to the point where I can't enjoy the cr anymore having to check the temperatures every minute.

Any recommendations?

 

[Senton_Prime]

You could start with that 20t but before you do any of that you should pull that HS and fan off the motor and get a nice fan setup!!

 

[Rowdyray]

Stock Granite is 15T. Stock Vorteks is 18 & 20T. Tried an 18T on my Granite and she got real warm. Wouldn't do it again without seriously upgrading the fans.

There's something different about the Vorteks I haven't figured out. All the gearing is the same as far as I can tell. The motor, heatsink and fan is the same. The Vorteks does have a different ESC. Not sure how they can get away with the 20T. Maybe tire size? Hopefully others can chime in. 'Cause I would like to know.

 

[Bustedaw11]

You could start with that 20t but before you do any of that you should pull that HS and fan off the motor and get a nice fan setup!!

+1
PowerHobbies 36-38mm mount. SurpassHobby Rocket fan. You can mount duals on that mount also if you'd wish too.
That stock heatsink is holding the fans back from doing thier job.

 

[Rowdyray]

+1
PowerHobbies 36-38mm mount. SurpassHobby Rocket fan. You can mount duals on that mount also if you'd wish too.
That stock heatsink is holding the fans back from doing thier job.

Yes, he could do that. But, it's still going to run hot. If either fan stops or gets a rock in it.....How can the Vorteks use the stock heatsink and fan with a 20T pinion, and not cook the motor?

The only thing I can come up with is the ESC is just a bit better. And the tires are slightly smaller in diameter. That changes gearing as well. What am I missing?

 

[Bustedaw11]

Yes, he could do that. But, it's still going to run hot. If either fan stops or gets a rock in it.....How can the Vorteks use the stock heatsink and fan with a 20T pinion, and not cook the motor? What am I missing?

How is the threat of debri more likely in your eyes because of an aftermarket fan? A shielded aftermarket fan is no different then a stock fan when it comes to the threat of debri stopping the fan. You'd be more easily aware with a rocket fan because they are loud and you'd easily hear that it wasn't running. Imo of course.

I don't know about your vorteks question, nor was I giving gearing advice for the granite. Only fan advice.
My guess would simply be tire diameter/weight possibly. Tire size directly affects over all gearing.

 

[Velodromed]

How can the Vorteks use the stock heatsink and fan with a 20T pinion, and not cook the motor?

That’s called the speed pinion. Straight line speed passes with rest between for the electrics to cool. Vorteks are not all around bashers like the granite or big rock. Run it through the same conditions and it will overheat with an 18 tooth pinion. Those lighter, lower profile tires are made more for high-speed gravel/dirt type situation’s.

 

[Rowdyray]

How is the threat of debri more likely in your eyes because of an aftermarket fan? A shielded aftermarket fan is no different then a stock fan when it comes to the threat of debri stopping the fan. You'd be more easily aware with a rocket fan because they are loud and you'd easily hear that it wasn't running. Imo of course.

I don't know about your vorteks question, nor was I giving gearing advice for the granite. Only fan advice.
My guess would simply be tire diameter/weight possibly. Tire size directly affects over all gearing.

You're missing my point. If you over gear it, it will over heat. You're telling the OP to RELY on better fans to cool it. If one or the other fails....you still do damage to the motor. Yes I've had debris get in my stock fans. Yes, I've heard them stop. I shut it down and fix it. But, I'm not over geared and less likely to do damage. Because it wasn't running hotter than it should.

I've said it before...over power, under volt. The OP would be better off putting a 4S system in it with a 20T pinion on 3S. Smoke any Vorteks out there and run cool all day even if the fans quit. Make sense now?

 

[Bustedaw11]

You're missing my point. If you over gear it, it will over heat. You're telling the OP to RELY on better fans to cool it. If one or the other fails....you still do damage to the motor. Yes I've had debris get in my stock fans. Yes, I've heard them stop. I shut it down and fix it. But, I'm not over geared and less likely to do damage. Because it wasn't running hotter than it should.

I've said it before...over power, under volt. The OP would be better off putting a 4S system in it with a 20T pinion on 3S. Smoke any Vorteks out there and run cool all day even if the fans quit. Make sense now?

Miscommunication on my part. Im Only offering advice on better cooling. No advice on gearing or thier effects. I'm not saying the fan will let him over gear for the conditions, as it won't. Gearing appropriate is a must. The fan is just a good idea in general because it will help lower the temps in general use.

If you want my opinion on the others- get a temp gun, gear up and when you start seeing the temps climbing under your normal driving conditions, drop a tooth. Nobody here knows exactly how you run so your the best judge by reading the data your truck will give you.

 

[RCbuzz]

Yes, he could do that. But, it's still going to run hot. If either fan stops or gets a rock in it.....How can the Vorteks use the stock heatsink and fan with a 20T pinion, and not cook the motor?

The only thing I can come up with is the ESC is just a bit better. And the tires are slightly smaller in diameter. That changes gearing as well. What am I missing?

It is the smaller diameter tires that change the ratio.

Also, smaller/lighter tires put less strain on the motor and esc.

High speeds though do consume serious amps and create a lot of heat

 

[Rowdyray]

Miscommunication on my part. Im Only offering advice on better cooling. No advice on gearing or thier effects. I'm not saying the fan will let him over gear for the conditions, as it won't. Gearing appropriate is a must. The fan is just a good idea in general because it will help lower the temps in general use.

If you want my opinion on the others- get a temp gun, gear up and when you start seeing the temps climbing under your normal driving conditions, drop a tooth. Nobody here knows exactly how you run so your the best judge by reading the data your truck will give you.

I know. And not trying to argue with you. Very valid points. Just don't want the OP burning up their RC chasing the stats of a different rig.

 

[Senton_Prime]

You can very well gear that thing up, if you loose that HS and fan for a quality setup it will free up a little room for the taller gears, I would advise not to gear it up until you know what your current temps are and after you get a good fan setup!!

 

[Rowdyray]

That’s called the speed pinion. Straight line speed passes with rest between for the electrics to cool. Vorteks are not all around bashers like the granite or big rock. Run it through the same conditions and it will overheat with an 18 tooth pinion. Those lighter, lower profile tires are made more for high-speed gravel/dirt type situation’s.

Now we're getting somewhere. I know what a speed pinion is. Lol.

They sure market it as the better Granite. But if I can't take it off road, how is that better?

It is the smaller diameter tires that change the ratio.

Also, smaller/lighter tires put less strain on the motor and esc.

High speeds though do consume serious amps and create a lot of heat

But, it's maybe a 1/2 inch. Makes that much of a difference?

 

[Velodromed]

Now we're getting somewhere. I know what a speed pinion is. Lol.

They sure market it as the better Granite. But if I can't take it off road, how is that better?



But, it's maybe a 1/2 inch. Makes that much of a difference?

It can go off road, but with the shorter suspension, lower profile wheels and lower stance, it can only do gravel and dirt road type stuff. Yes the tires make a big difference. Put granite tires on a vorteks and that’s a whole different critter. Turn it into a 4s beast and you have this… I know the vorteks and entire 3/4s line very well.