Upgrade a curtis controller or buy a new Kelly KDH12100?

I built a racing 125cc GoKart with a D&D ES15A motor 240 A123 Cell (30S8P) 99 Volt nominal, with a Kelly KDH96500A (96 Volt, 120 Max, 500 Amp max (10second) 400 Amp 1 minutes… I’m disapointed(I want instant torque) by the slow current ramping, it’s only consuming 100 battery Amp at start up and will reach 375 Amp max (battery current)

Here is my project: Robin Almasi’s 2005 BRM Racing Go Kart

The question is, do I upgrade for the Kelly 120 Volt (136 max) 1000 Amp or I try to modify a old Curtis Golf cart controller with new high voltage mosfet with much lower ON resistance…?

I don’t want to spend the 3000$ for a Zilla 1K…but I know it’s what I want!

Robin Almasi

the kelly controllers are notorious for being underpowered… if you want 500A, get a 1000A controller. The current drops off quickly.

Otherwise a 500A curtis would be great and offer better peak current for longer.