When running two motors together on the same spur, it's best to run batteries in parallel before the voltage gets to the ESC. This is to make sure that both motors get the SAME voltage going to them. Otherwise, if you simply hook up each pack to an ESC, the motors could be getting different voltages which would cause them to work against each other.
In general though, dual BL isn't the way to go. You can get a single, more powerful motor and end up with a more efficient setup that weighs less, and only requires one ESC. Also, dual 6XLs aren't ideal, if you do go dual IMO, especially on 5s. If your mind cannot be changed on the dual motor idea, then get 9XLs at least.
SH Z-Car, Custom Crawler, 8s Savage, 12s XTM XLB 1/7 buggy, 4wd 4-link rear/IFS Pro4 truck, Custom Hyper 10 Short Course, Belt-Drive Mammoth ST 1/8 truggy, 4s 17.5 MM Pro HPI Blitz
When running two motors together on the same spur, it's best to run batteries in parallel before the voltage gets to the ESC. This is to make sure that both motors get the SAME voltage going to them. Otherwise, if you simply hook up each pack to an ESC, the motors could be getting different voltages which would cause them to work against each other.
In general though, dual BL isn't the way to go. You can get a single, more powerful motor and end up with a more efficient setup that weighs less, and only requires one ESC. Also, dual 6XLs aren't ideal, if you do go dual IMO, especially on 5s. If your mind cannot be changed on the dual motor idea, then get 9XLs at least.
I'm thinking twin 7XL's. I run a single 7XL now on 6S on one of my emaxx's and it does awesome.