There is an option in mod that rebalances vanilla fuel and there is a very strange part in it
data.raw.item["rocket-fuel"].fuel_acceleration_multiplier = 1.5
data.raw.item["rocket-fuel"].fuel_top_speed_multiplier = 1.5
data.raw.item["nuclear-fuel"].fuel_acceleration_multiplier = 1.25
data.raw.item["nuclear-fuel"].fuel_top_speed_multiplier = 1.25
So it makes nuclear fuel worse than rocket-fuel. Recipe wise it should be an enhanced version of rocket fuel.
Looks like a bug to me, but a suggestion, maybe multipliers for nuclear should be 1.75?
But then there is also "k-antimatter-capsule" which is defined in item.lua
and it has this values defined like this
fuel_acceleration_multiplier = 1.25,
fuel_top_speed_multiplier = 1.5,
I think they should be buffed too? maybe 2.0 for both?