whats the easiest way to make a rancher 4x4 ES go 55?
will a high lifter performance kit make it go faster?

 

First you need bigger tires OR an remove the rev limiter, (no idea on how to do that on the rancher myself), 26" meats should do it with the factory set redline. Then you need the guts to pull them, a good start would be the K&N power kit, maybe a pipe too (K&N's kit claims to give a 15% power boost, sounds like a bunch of bull to me I'd need to see it to beleive it on a dyno myself.) If that doesn't do it major expenses could be racked up with actual engine mods.