In theory you can do that. In fact, a lot of offroaders use 2 to 3 2s packs to make it 4s and 6s (high voltage operations). The only concern is you cannot balance charge the packs, and if the packs are out of balance, you may swell the pack during your 2s operation.
Thanks,
I am not sure if the 1S lip for pan car is the same as those ordinary LiPo. If yes, I think it will be okay since those 966E also use 4 saddle in serial.
I want to know if there is any CHing really tried this out. I do not want to ruin my batteries.