run times?
 

I am going to build a GTP chassis kit. I will be using a RCM motor mount and mmm 2200kv. I plan on using 2 2s lipo packs @14.8v with a mah of 4000 each. What kind of run times am I looking at? I will be modifying drift type tires not too much topend speed runs here just want a 1/8 scale drifting beast. Thanks

Somewhere between 10 and 20 minutes of runtime depending on driving style and gearing. Sorry it's such a broad range, but those are the biggest variables.

thanks I just want to make sure of a few things before I pull the trigger. I am use to 45min run times with my gas burner. This car will be a in between you know. On road is all new to me. I like the speed and agility of even the mildest brushless set up. One thing for sure I want to spend money in the right way and not end up with an expensive piece of shit.

unless you run 40c packs 4000mah will not be enough. Go up to 5000 35c min. I would run a pair of 3000+mah 4s packs in parallel for better runtime. Or go up to 5-6s.

how about 2 4s 5400mah 25c 7.4v? Will I be better off with the MMM 2650kv ?

The 2200 will be a better motor choice IMO. Undrstanding Lipo ratings is a good start. Lets start with the last packs you mentioned, 5400mah 25C aka 5.4Ah 25C. 5.4 x 25 +135Amp continuous output. iirc it is recomended to have batteries capable of 150amp continuous with the MMM. However the quality of the battery and what kind of current draw you will place on them is also a big factor. If your gearing for 30MPH or 50MPH is going to have a big effect. I ran 4500mah 25C batteries all summer in my truggy without an issue. It was a 5s setup geared for about 36MPH though, my average amp draw was less than 20amps.

I found 130amp continuous 5200ah 4s 7.4v Tenergy. I have had great service from my daughters 1/18 with CC sidewinder and a 2s 1600ah lipo. That little b-tard is quick and runs for a good 10mins or better.

My best advise is to list all of the lipo info for us and someone who tried the pack can chime in and tell you if they are worth it or not. Big 1/8 stuff can draw some amps, especially on 4s lipo.

After puffing and killing alot of lipos I have to say that enerland and zippy seem to be the best bet. I would not buy a cheap lipo other than zippy. The hyperion g3 packs look to be the best brand name for the price option right now... I just picked up a zippy 5000 40c 6s for my lst projects, we will see how it does.