The overall "best fitment" depends on the Rim size you use.
The basics...
Bolt pattern = 4 X 108mm (4.25 inches spacing)
Cutout diameter 62~63mm (inner cutout hole for Axle/Shaft)
Offset (where Rim sticks out or in) is 45~47mm Positive (Rim goes in towards hub)
Rim widths...
15" = 6 inch width
16" = 6.5 inch width
17" = 7 inch width
The overall diameter they (FORD) would rather see you use in between 23.5 to 24.5 inches diameter to fit the wheel well in diameter, the width though - is a little more tricky.
The WIDER the rim, forces you to run a WIDER tire - which goes against the geometry of the car. It would really like to keep itself going on 185 to 195 width tires - anything above that might put your car in the shop due to damages the extra wide sizes can do to the torque of the suspension, steering, fuel economy, let alone, wreck the fender and wheel well.
With 15" you have a Rim width of 6 inches - plenty to work with so tires of up to 205 width (205/60R15) work well.- the Offset is necessary to be kept between 45 to 47mm (and it's positive) - so the Steering Knuckle and it's geometry - the main thrust, axial and weight - are right on the strut, lower control arm and ball-joint / steering knuckle 3-point bearing setup they use. (I currently use B.F. Goodrich Advantage on 15 x 6 - 4X108)
Many just go with 185 / 65 / 15 on up to 225 / 40 / 15 (wider tires are more of a clearance issue than versus the working diameter)
I currently use 16" Rims with the 6.5 inch width - Optimo's are the Ford OEM and are 195 / 50 / 16 - and I'm shopping for 185 / 60 / 16 to give me up to 24.5" diameter - the Optimos', when new - ,are at 24.3 in diameter to start with. I did a write up on my Tire experience not too long ago on this and I don't recommend them - they are not a good fit for someone whom either drives streets or does have to deal with winter and potholes. I use the 15" 185/65/15 for winter (B.F. Goodrich Advantage)
Others that go to 17" rims, the feedback I /we see in problems - that really is too wide and gets a little too thin to provide safe sidewall protection and flex for rougher roads - no matter the width. And they REQUIRE you to use a wide tire of 205 and up (as to seal the bead to the rim) - which will begin to start that scraping and clearance damages the wheel well and fender the road bumps can get it into ... I mentioned that earlier. (Remember Overall best diameter is between 23.5 to 24.5)
You'll also discover another quirk; that is to the geometry. And that is dealing with Toe-In/out and the Caster/Camber the front steering has - wider tires MAGNIFY alignment aberrations. It will fight you and the road, wearing out the tires, you and the suspension soon enough - and the replacement costs of all that torque you will be placing on the car from simple road to tire friction and uneven surface and road crown drift - will cause you to part with...a lot of $$$
Remember too, the spare tire is usually about a 23 inch diameter like 175/80/14 so it's the BARE minimum and uses a rim width of 5" - Why care? Hmm... Just in case your stranded after debris or road hazard and got a flat tire from it - can you use the spare tire to get you to a shop safely to fix the busted tire and or bent rim (usually that requires replacement) ?
- You may find yourself having to relocate a good tire from one axle to replace the busted one on the other, then install and use the spare where the good one was, just to get it to roll along to provide enough clearance from the road so the car can get somewhere to fix the problem without scraping the muffler, undercarriage or front bumper and it's skirt on the ground from the angle the car will lean into. Caused by the smaller diameter tire due to the odd-ball sizing
You did ask...
Hope this helps.
too bad, so sad haha.
