how much better are lipo over nimh

[Aaran]

currently running some matched nosram 4600 saddles in my car with a nosram matrix istc esc and a 4.5 turn nosram pure brushless.

how much extra runtime and power am i likely to get switching over to say 5900mah 2s lipo with a 40c discharge rate?

where we race its mostly long straights and the battery jsut lasts 5 mins if im carefull with the fun trigger.

thanks in advance