runtime vs power
 

hey guyz im stuck between geting a 7xl and a 8xl i was wondering what run time i will get with them i know the 7xl will be more power full and the 8 will run longer but is the differance that great between them? i will have them on a mm and 2 2s2p 8000mah lipos from maxamps i would like to do about 40 for 30min i know for run time u will say 8xl but if the 7xl can do like 25min i may go for that please teach me sensei's

I think you'll be more than happy with the 8XL. It's the best compromise between runtime and power for 4s IMO. And if it's not quite fast enough, you can always increase the pinion tooth...

And with the 7XL you might run into problems with the temp. on the MM. On mine, I have to run a fan to keep the MM cool with the 7XL.

have u ever run a 8xl metalman do u know if the power diff is really that great?
that it would make the esc heat up?

I haven't used an 8XL, but assuming that you were to use a lower gear ratio with the 8XL than with the 7XL, the power difference shouldn't be too noticeable.

I don't know what metalman is running his 7XL in, but I am running one in a buggy conversion with a MM on 4S and haven't had any heat problems, although I am running a 30mm fan on the MM and a 12v 40mm fan on the motor. The combination in a buggy EASILY does 40mph. I'm almost sure that an 8XL will be able to attain that speed, though you'd probably have to work with the gearing. I'm thinking of getting an 8XL for my buggy for the sake of gaining runtime. With my 7XL and a 14T pinion, I've done a few practice runs with people that happened to be out at the track and so nothing has even come close to being able to keep up. I think that I can afford to sacrifice some speed for more runtime.

It's in a Revo on 16.5v. Larger tires and higher voltage mean more stress.

MetalMan,

I'm thinking of doing a truck as my next project. Just something for bashing and all around clowning around. I was thinking of doing a Monster GT, just because they are so easy to work on. I'd also like to do 4S, if possible in a truck that size. I just like the MM esc. What do you think of a 10XL?