jnev,
I agree w/ you on keeping the stock chassis so you have different sizes. If I wanted a 1/10 I would have built a 1/10.
I agree with everyone else that it will be a little fat on 4s 5000mah. Thats a pack that most run in a 1/89 buggy.
I am running 3s 3300mah and 3700mah packs and get around 20-25min runtime with them using a Hacker 8L and geared for around 45mph. I could probably get more runtime if i tamed the gearing down a bit, but I tend to be a bit of a speed freak. When Im running it, its usually with 1/8 buggies so I cant have them be faster than me.
Mine looks very similar to most others heres a couple pictures.
Instead of going with 1 5000mah pack I would almost think you could find 2 3000mah or so packs and then have 2 to switch back and forth. 1 charging and 1 running. On 4s 3000mah you should get some decent run time I would think.
