Currently run 2-5 cell in series 5300mah 60c (Gens Ace) in 40" deep vee, Leo 5692 780kv with X455, runs nice and cool in low to middle 50's mph. Other than losing a little in acceleration (not planning on racing) would top speed be effected if i changed batteries to higher mah with lower c. I know it would give me longer run time Was thinking about 5 cell- 8000mah 30c or 35c Planning on prop upgrades next year too. Still trying to work out larger dia. or more pitch to get more top speed. Thanks for any and all imput.