tc4 speed car
 

ok i have been testing my tc4 with a mamba max 7700,4 cell flight power 2500 25c lipo battery,ccbec,novak glich buster cap and 31/69 gearing.well i was hoping for 95-100 mph and i dont know if my gearing is holding me back or what but after testing 3 or 4 battery packs i had a consistant top speed of 81 mph and that was well under my expectations of 100 mph. will a change of four teeth on my pinion gear realy add 20 mph to my top speed?.is thare somting that im missing?

RE: tc4 speed car
 

The 7700 motor wasn't built to handle anything higher than a 2s lipo. Have you considered trying either the 4600 or 5700 with the same gearing?

RE: tc4 speed car
 

I think once you reach 80+ its starts to come down to setups and aerodynamics personally seems you have enough power so alter your gearing and dial in your Suspension etc and try some different setups out.

RE: tc4 speed car
 

Is that lipo 2500 as in 2500mah? seems quite small...
Im not to updated on lipos so excuse if ive got that bit wrong i know generally in nimhs the more mah the more runtime but i find larger mah pack to boost power too ;)

RE: tc4 speed car
 

t9dragon yes the 7700 is limited to a 2cell lipo but thare are alot of pepole that are using the 7700 on 4-5 cell lipo and reaching speeds up to 135 mph with tc4's.i think you might be right TIGER76 about the setup and aerodynamics of the car im going to change my pinion ger from 31 to 35 and lower it alittlebit. iv been waiting for the administraitor of rc-isc to activate my acount so i can talk to vasmar and nick case about this.yes 2500mah vasmar used 3700mah to go 135mph!

RE: tc4 speed car
 

25cX2500=62500 divided by 1000= the battery is only rated for 62.5 amps.. That motor and all is probably pulling around 1000.. Its your battery.

RE: tc4 speed car
 

thats the minmum the max burst is 125.0 amps.plus thare only 44 bucks esaly replacible.

RE: tc4 speed car
 

getting closer 31/69 gearing 4s lipo = 86 mph

RE: tc4 speed car
 

Are you using a gyro in there somewhere? Or a really wide road? Nice work!

RE: tc4 speed car
 

nope no gyro just 6 years of driving rc cars and alot of crashing lol [sm=cry_smile.gif]

RE: tc4 speed car
 

Keep at it m8 ;)and would love to see a video soon i like the rc speed vids there awesome[8D] the noise of a rc flyby at 80+ is amazing [X(]

RE: tc4 speed car
 

R.I.P mamba max esc she died at 86 mph:( up next mamba monster max 75% throtle 6s lipo[X(][>:]

RE: tc4 speed car
 

i know its a bad video but you can still see the car.in this video i was reaching speed up to 73 mph at 3/4 throtle.[link=http://www.youtube.com/watch?v=6dlIfEY-T3I]http://www.youtube.com/watch?v=6dlIfEY-T3I[/link]

RE: tc4 speed car
 

That's not ideal mate.

The lipo is too small. The battery forms the base for everything else. You could have a neu 1527 in there with a big ass HV MGM controller, but if you then supply it with a 10s pack made from 2500mah 25c cells it ain't gonna perform well. That 7700 will be pulling huge amps even on 5s (you should realise this, you fried the Mamba Max), I doubt you have enough headroom on the battery amp draw to allow it to keep the cell voltage up during long periods of wide open throttle.

Vasmar may have made 135mph on 3700 (I'm betting that was at higher voltage too, meaning his amp peaks would be lower), but that meant his batteries (assuming a 25c draw capacity too) had a 50% increase in the amps they could pull lumped on top of both the continuous and burst ratings. That is a huge advantage.