Wow, I see.

Well, I'm not sure about what cap you are wanting to add.

Do you mean a "glitchbuster" cap to help the BEC cope? If so, that won't work; all it will do is help even the load (smooth out the current spikes). And with tires that big, there is quite a load on the steering servo and BEC. Plain and simple: you need a switching one.

Or, do you mean extra caps on the power lead to augment the existing 3 caps on the ESC? If so, that may help (certainly won't hurt), but I wouldn't expect miracles.

I think your best bet would be to get a UBEC and possibly gear down a tooth or two. A 2700kv motor on 3s is only ~29k rpm, which a bit on the slow side. The ESC may simply be pulling a decent amount of current to retain 35mph speeds. With that motor and tire size, I'd go 4s and gear to 11T or 12T on the pinion. But at 4s, a UBEC is required.

Yes I talk about a extra cap 1200UF/35V

what happened if I used heavier diff fluid on the rear diff then the front diff ?

http://richtechparts.com/i-2564-1200UF_35V.html

do you think these one are low ESR ?

Probably. The 105*C temperature rating is usually low-ESR. The regular style caps are usually rated for 85*C.

ok good!

it is possible my 4.72inch tires with the balloning factor goes up to 6inch ? and the speed at 4.72inch are 33.67 mph (54.08 km/h) and with the ballooning the speed goes up to 51.93 mph (83.41 km/h) ...

Could very well be.

im back from playing with the crt.5 and I have strapped the GPS the top speed was 39.37 mph (63.25 km/h) the runtime with a 3s 6400mah was 32 minutes I runned 13.2km ( kilometers ) in total.. the outside temp was 13°c ( 55f ) and at the end of the run the motor was 95f and the speed 95f too no body in it and bec disabled ...

anyone can diagnostic my amps draw from this info ?

and for my rx pack I used 425mah for 32minutes of runtime

so with a bec or not it wont really affect the runtime on the main battery I think ... maybe only around 2 minutes ? :smile:

rx 425/32*60=800mah = 0.8amps

Bat = 6400/32 *60= 12 amps