Converting a x1cr jammin to bl
 

Witch motor should i choose?
A feiago 8xl or feiago 8l?
With the 8xl i`m going to use 4s and with the 8l i`m going to use 3s.
Witch one is the best choice?
What is the corect gearing on theese motors?
I'm planing to use stock spure.
Is there a big difference between thees choices? Wil the 8xl be quicker than the 8L?
The esc will be Quark 125b:004:

9XL on 4s.

Please read the sticky in the brushless section about 'brushless in general'

the 8L is a very hot motor, and an MT/truggy at 3S is quite current hungry.

For racing the 9XL on 4S is up the task.

If you are going to be racing, the 9XL is going to be the way to go. Depending on how tight your track is, you might even be better served by the 10XL.

Don't get fooled by the high kv ratings of some motors. With the Feigaos especially, you'll want a large can (XL) motor with a relatively low kv rating on 4S lipo and take advantage of all of the torque and gear up to attain speed.

I have a thread in the brushless section entitled something like 8ight T 9XL or something like that. I have a link to a video in there that will give you an idea of the kind of performance that you can expect.