Which Speedo Gear

[josh_hartman]

Now i am changing to a 3.45 lsd and i need to find what speedo gear i need. my wheels are 18s with 235/40 tyres. I also want to run a xr speedo so i actually need 2 but dont know when i can get the cluster so yeh. i have a S1 au forte auto. i did try see ford but they dont know crap here. thanks

[FGII-XR6]

with that tyre combination and a 3.45 you need a black gear which will give you an error of -0.26% you don't get better than that. The cluster makes no difference to you reading they are internally calibrated for the speed range on the face and use the same sender and gear calcs