Nick481

I was thinking about getting one of the unnassembled kits like the HPI f10 or the tamiya f104 kits and putting a brushless system in them. I want it to be more of a speed car, not a low geared car made for the track. Like 60+ mph. My question is, do 540 size brushless motors fit into these types of kits, and can their gearing be changed for higher speeds? I am also wondering if the driveline components will be able to hold up to that power of a motor. Are there aftermarket parts that are stronger for the driveline?
Thanks,
Nikkolas

collector1231

My Feedback: (1)

540s should fit in there. Stock everything should be okay, but if you strip something, replace it with metal. Most plastic gears handle BL just fine.

Eman77

Err, isn't 540 the standard size for most/all 1/10 anyway?

Nick481

Would you guya recommend a lower turn motor with higher kv like a 8.5 turn with 4000kv because pinion gears can only get so big, and i know these things stock with a brushed motor are geared about 30 mph ive heard. I dont know for sure what the difference in rpm's between a 4000kv 8.5 turn brushless and a brushed 540.

Vyger

Either car will handle a 540 size motor, brushed or brushless. The stock gearing will and motor combo is no where near 30mph. Maybe if they're going down hill with the wind to their back, or if you throw it. The top speed for a stock 104 or F10 is about 22mph. The cars gearing is direct drive and should be able to handle anything you can throw at it, if your gear mesh is set correctly. Good luck running the 8.5...these aren't 1/12 scale cars.

Nick481

Assuming the differential is a 1:1 ratio which i think it is, 7.4 volt lipo with a 4000kv motor with 2.5 inch diameter tires, 75 tooth spur gear and 25 tooth pinion gear theoretically is 73 mph. Am i doing something wrong? That might be too high gearing for that motor anyways, but a 3500kv on 3s lipo might do the trick too. The only problem is battery size. Does anyone know the battery compartment dimensions?

Vyger

Well, I see your theory, but I'm not 100% sure about it. I run a 7.4 shorty lipo, 21.5 motor, 93 spur, 34 pinion. I have no idea what the kv rating is on the motor. It's a Novak 21.5 ballistic. The tire size is the standard rubber tires from Pit.

The battery compartment is limited to the standard 6 cell nicad or 2 cell lipo. I use the shorty pack.

Nick481

Your motor is 1800kv and with a 7.4 volt battery, it turns a maximum 13,320 rpm. With a motor of 9 turns and 4300kv on 7.4 volts it would turn almost 32,000 rpm but would have less torque. Arent these cars super light though? Im probably going to do the formula 10, but isnt it under 2 pounds ready to run? If so than a 9 turn might be enough even on high gearing. Btw, how many mah is your 7.4 lipo?
thanks,
Nikkolas

Vyger

My batteries are 4100mah, 65c, the cars are super light fully loaded, but I don't have any specifics with regards to weight. Just a suggestion with regards to the chassis choices, I'd probably go with a Tamiya F104 something instead of the F10. The reason I say this is there are more places to get parts for the Tamiya and a lot of people on here and other forums can help you with set ups. The F10 sort of came and went...I know...I have one. LOL

Nick481

I wanted to get an f104 the only problem is money so i have to get an f10 . But i think i might finally have everything figured thanks to your guy's help. One more question though, does the body come pre trimmed on the f10 or do i have to trim it? And another question: ae there any soft compound rubber or even foam tires and wheels that fit the F10 other than the hpi bridgestones, and maybe even some wider back tires? Also if anyone can maybe chime in on how they think a 9 turn will do with high speeds and a 2s lipo, it would be greatly appreciated. Thanks for your time everyone.
Nikkolas

bobbyvega$

You'll be waisting your time, these F1 cars are quick enough with a 21.5 let alone a 17.5 motor.....anything over that and traction even in a straight line will be a problem.

Nick481

Haha i ended up getting an rj speed dragtser and i hit 100 mph with it this week on a 2 cell lipo. Im glad i bought it instead of an f1 car.

bobbyvega$

nice!!!