If you want to use a Feigao "L" motor, you are going to need to run more voltage than that. How about 2 of the packs you listed in series, running two 8Ls? That would make your 4x4 Pede pretty fast! But, the tires could possibly be too large for the 8L. If that were the case, then 2 9Ls would work.
BTW, if you want to see a how-to for a 4x4 'Pede, you can see mine that I made when I had my 4x4 'Pede back 1 1/2 years ago:
http://4x4pede.freehomepage.com/
(sorry about all of the popups. It's free webhosting...)
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