yes you can do that and it will work well. Running 4s doesn't draw as much current as many think, they draw considerably less then a 4x4 sc on 2s. Running 2 quality shorty packs will work well for a light weight set up. Some companies also make a shorty 4s pack for single pack cars (I know SMC makes a 4600mah 4s shorty, not sure who else)