mamba 4600 on 4s or 6900 on 3s? which is faster?

[BL_RV0]

i decided i am going to go BL/lipo in my tc3 now. itll be a PURE speed machine. which of the 2 setups in the title will be faster?

[BL-Power]

4600rpm/V x 14,8V = 68080rpm
6900rpm/V x 11,1V = 76590rpm

=> The 6900 on 3S will spin faster.

[BrianG]

Although the 4600/4s combo may tolerate higher gearing better since you're looking for high speeds only...

[bdebde]

Both are over the max rpm of the motor, I would go with the higher voltage set up, may run a bit cooler.

[BL_RV0]

yeah, thats what i was thinking. thanks guys. ill have it ordered within the month.

[snellemin]

Pick the lower kv motor and gear up. I only dragrace with 5000kV motors and below. The higher kv motors just draw too many amps, dropping the voltage too low, making reaching the topend harder.

[Arct1k]

Just a thought - why not a 5700 on 4s A123 as a compromise - I think this is what stampedeproject was running...

[speedracer1129]

I am running a TC4 I just finished. 4600 on 4S with 25/75...74mph!! Motor and ESC temps at 100 or so!!! It is a good setup for playing around. Easy 20 minutes on Apogee 3800's. I dropped in a 5700 to see what it will do Wednesday night.......

Funny thing, I did this setup once before with a Cyclone and junked it because the 4600 on 4S would melt the diffs after 2-3 runs!! Few months later, I help someone setup a bone stock HPI Sprint 2 w/ a 7700 on 3S with 33/81 gearing and WHAM, 84mph on the radar!!!!! SOOOO, I am back again to prove a point!!

[speedracer1129]

Originally Posted by speedracer1129

I am running a TC4 I just finished. 4600 on 4S with 25/75...74mph!! Motor and ESC temps at 100 or so!!! It is a good setup for playing around. Easy 20 minutes on Apogee 3800's. I dropped in a 5700 to see what it will do Wednesday night.......

Funny thing, I did this setup once before with a Cyclone and junked it because the 4600 on 4S would melt the diffs after 2-3 runs!! Few months later, I help someone setup a bone stock HPI Sprint 2 w/ a 7700 on 3S with 33/81 gearing and WHAM, 84mph on the radar!!!!! SOOOO, I am back again to prove a point!!

Just an update: 5700 on 4S, 32/69.........84mph!!! Slowly climbing

[SpEEdyBL]

Do you have to use the mamba motors? The novak 3.5r went 79 mph one year at the worlds fastest rc-car challenge on just 2s. Last year the HV4.5 went over 100 mph on 4s and 118 on 5s. These were just off the shelf setups too.

[snellemin]

I use to run 4s A123 with the 5700. It was silly fast, but heated up to quick.

Originally Posted by Arct1k

Just a thought - why not a 5700 on 4s A123 as a compromise - I think this is what stampedeproject was running...

[Pedebeater]

You guys know that the 6900 should not be ran on 3s right? It is not made for that high of rpm, and will heat up very fast. Not a good idea imo.

[Takedown]

Like PB said. Not only will it be dangerous and void the warranty it will heat up very quickly. Castle motors tend to do that...

[snellemin]

You forgot that you are on the RCM forum. The peeps here are brushless experts.

[Takedown]

Originally Posted by snellemin

You forgot that you are on the RCM forum. The peeps here are brushless experts.

I guess... I still wouldnt use Castle motors if your going for all out insanity.