Archived from sn95brakes.com

5 Lug:

When choosing wheels, it is always easier to pick out the wheels you want to run first before doing modifications for them to fit.  This is going to be a 5 lug OEM wheel guide mostly dealing with the 17" wheels for the 94+ mustangs.  Keep in mind that you will need to roll the fenders front and rear when running wider rubber than stock to at least get the edges away from the tires and pointing up.  The newer 91-93 fenders should give a bit more clearance, but nothing to dramatic or required for most tire/wheel combos.

Up Front:

If you are going 9" wide wheels, then you will need to run the 94-95 spindles.  The 96+ units will increase the front track 5-8mm per side and that will cause rubbing problems with the 9" wide wheels.  You will need to run the 24mm offset and 5.95" BS for the 9" wide wheels.  Expect the wheel to rub on the back of the A arm on the jacking pad.  You can eleviate this by grinding the jacking pad off and/or using the Ford rack limiters.  Also some tubular A arms are bent to help with this problem.  I would not recommend any wheels wider than 9" without special A arms with more clearance on the rear of the A arm.  Also 18x9" and 18x9.5" wheels will have the same issues as a wider than 9" on the back of the A arms.

If you are using the 8" wheels, you should be fine with the 94-95 and Modular 96+ spindles with some possible minor fender rubbing.

Here is a list of OEM wheels that require you to use the SN95 spindles and brakes to bolt them up:

1998 Cobra
1999+ Cobra
1997+ Mustang GT 17" wheels including the Bullitts
2000 Cobra R

Out Back:

Out back the wheel selection is up to the axle length that you use.  

If you keep the stock track, you can run the same wheels front and rear when you run a 9" wide wheel like the R58 Cobra R rims.  You can also run any of the 8" wide rims, but they will sit in a bit since the rear track is narrower than the front track stock on the fox3 mustang.

If you use the SN95 axles (1994-1998 Mustang) they are 3/4" wider per side than the stockers.  If you run 8" wide wheels, it will bring the wheels out the edge of the body to make the front and rear track more even looking on the body lines of the car.  Most people prefer this.  Now if you are going to use 9" wide wheels on the Sn95 axles, then you need a special offset wheel out back like the M179 Cobra R wheel that uses a 36mm offset and 6.42" BS.  This will stick the wheel back in so it clears the fender opening on the body.  With the longer axles out back, you will have to use 2 different wheels to run 9" wide rims, thus the stock rear track is preferred here.

If you dare to use the Lincoln Mark7/SVO axles, they are 1 1/4" longer than stock.  You will have to run special offset rims in the rear with 8 and 9" wide wheels.  I have seen some of the OEM 17x8s on the Saleen mustang work, but it is tight.  You will need to do some major fender rolling here in the rear to clear things.  Good luck here!  You may be better off getting some ranger axles and doing the flip comversion to get back to a stock rear track length.  

Spare Tires

When converting from 4 to 5 lug wheels or from the 94+ GT/V6 brakes to the 13” units, you are going to have to address the spare tire for street use.

You can find 5 lug Ford spare tires with the 5 x 4.5” bolt pattern on many vehicles.  Rangers, Explorers, Bronco II, Lincolns, Crown Victorias and the 94+ Mustangs to name a few. Most of the spare tires you will find will be 15” in size.  This is the stock spare tire size on the 94+ Mustangs also with the GT and V6 package.  So if you are upgrading to the GT/V6 brakes, you should not have a problem finding a spare.

Now when you upgrade to the 13” brakes, the cobras come with a special sized spare tire to fit the larger brake rotors.  These are not easy to find and can be costly when you do find one.

There is another solution.  Get a 15 or 16” spare from one of the many applications already listed.  Now that spare will not clear the front 13” brakes, but will clear the rear brakes just fine.  So if you get a flat on the rear, you can just change the tire with the spare.  Now if you get a flat in the front tire, what you are going to have to do first is change the spare to the rear tire.  Then take the rear tire and swap it with the front one.  Keep in mind that this trick only works if you have the same sized wheels on all 4 corners of the car.  If you do not, then plan to spend the money for the 94+ cobra spare.

4 Lug:

To run wheels such as the 93 Cobra units, you have to understand the offset required.  The front and rear track was 3/4" longer than a stock 5.0 of the 87-93 cars and they have special offset wheels.  To run these wheels up front on a 87-93 V8 car, go purchase the 93 Cobra rotors.  They are the same everything as the 87-93 units, but with a 3/4" taller hat on them to widen the front track.

Out back, the 93 Cobra uses the same brakes and axle lengths as the 87-88 Turbo Coupe which was 3/4" wider than stock. So if you are using drums, you can run a 3/4" spacer (which is not recommended) or use the brakes and axles from one of these cars.

If you use like the Pony wheels on the rear of the TC or 93 Cobra rear end, be sure that you roll the fenders.  Also make sure that your UCA bushings are centered in the arms.