Just some info on chips. Most of the cheaper ones only intruduce more fuel thus costing you more and shortening the life of the engine. That's why they are cheap. The dearer ones do much more than introduce more fuel. There's about ten different parameters that they moniter and adjust. Air flow, injector timing and duration, and fuel pressure on the common rail engines are just a few. This all helps to prolong the life of the engine without compromising on power, torque and fuel. For the most part fuel consumption will not change under normal driving conditions. Towing is where the difference is as fuel consumption can be reduced. The best performance can be gained with a 3" exhaust system as well.

With the correct cable and program the parameters on the Tunit chip can be changed to overcome small problems that may arise, with consultation from the supplier. The variable resistor in these chips is for de-tuning or tuning up the performance of the engine according to your needs. Of all the chips available there is only chip that puts their money were there mouth is. Tunit have a 3 year warranty and then offer a 12 month warranty on engine and driveline for any vehicle up to 5 years old.

My advice, the cheaper chips might be easier on your pocket now, but if you plan on keeping your beloved Patrol for a long time then pay the extra for a dearer chip, or you might just be paying out for a new engine as well.