Hi
I think the main issue with your car is brain, the land-rover standard ECU sets the fuel mixture every 1000rpm , by adding the chip it will be corrected every 100RPM this does away the steps in acceleration, The RPI chip is ok but I believe John McDonald retails one which is set up specifically for +8's ( light car ) wereas the RPI one is a general chip , If you are not looking at performance this is the only mod I would make .
Cheers
Alan
