Bruce,
the 140-7017dp will add 1/2'' of track width to each side.They suggest installing this kit before ordering wheels just for this reason.They also have a kit that keeps your original width.
B1F 2427402ZFSL
12.19" x .810"
4 Piston Forged Superlite
Note 4 - Does not add to track width. Zero offset
http://www.hotrodheaven.com/tech/bra...akes_index.htm
Mustang II Disc Brake Kits
We have a wide selection of brake kits for your Mustang II Conversion. We always recommend the purchase of the Wilwood brake kits over the OEM (factory) type because of the amount of pressure that is required to operate the GM calipers. What you save on your initial purchase will be lost with the headaches, time and parts you have to buy in addition to the normal master cylinder used with a 4 piston caliper kit. Please take the time to read the Brake Article and Frequent Asked Question, the time you spend reading this will be well worth your trouble and might even save someone's life. Includes free shipping to lower 48 states.
Part Number
Size Rotors
(Note 1)
Type of Calipers
(Note 2)
Notes
WIL 140-2129
10.75 x .810
4 Piston Dynalite Calipers
Note 3
WIL 1408652
11.00 x .810"
4 Piston Dynalite Calipers
Note 3
WIL 140-7017
12.19 x .810
4 Piston Dynalite Calipers
Note 3
WIL 140-7018
12.90 x 1.10
6 Piston Superlite 6 Calipers
Note 3
B1F 2427401ZFSL
11.75 x .810
4 Piston Forged Superlite
Note 4
B1F 2427401ZFSLSC
11.75 x .810
Scallop
4 Piston Forged Superlite
Note 4 & 7
B1F 2427402ZFSL
12.19" x .810"
4 Piston Forged Superlite
Note 4
B1F 2427402ZFSLSC
12.19" x .810"
Scallop
4 Piston Forged Superlite
Note 4& 7
B1F 2427403ZSL6
12.90 x 1.10
6 Piston Superlite 6 Calipers
Note 4
B1F 2427403ZSLSC
12.90 x 1.10
Scallop
6 Piston Superlite 6 Calipers
Note 4 & 7
B1F 2427401-125ZFSL
11.75 x 1.25
4 Piston Forged Superlite
Note 4
B1F 2427401-125ZSL6
11.75 x 1.25
6 Piston Superlite 6 Calipers
Note 4
B1F 2427401-125ZSLSC
11.75 x 1.25
Scallop
6 Piston Superlite 6 Calipers
Note 4 & 7
B1F 2427402-125ZFSL
12.19 x 1.25
4 Piston Forged Superlite
Note 4
B1F 2427402-125ZSL6
12.19 x 1.25
6 Piston Superlite 6 Calipers
Note 4
B1F 2427402-125ZSLSC
12.19 x 1.25
Scallop
6 Piston Superlite 6 Calipers
Note 4 & 7
B1F 2427403-138SL6
12.90 x 1.38
6 Piston Superlite 6 Calipers
Note 8
B1F 2427403-138SLSC
12.90 x 1.38
Scallop
6 Piston Superlite 6 Calipers
Note 7 & 8
Note 1: Add "D" to the part number for Drilled and Slotted Rotors
Note 2: Add "P" to the part number for Polished Wilwood Calipers
Note 3: Adds approximately 1" total to track width (1/2" per side). Recommend installing brake kit before purchasing wheels.
Note 4: Does not add to track width. Zero offset
Note 5: 2" drop generic spindles with Wilwood hubs, rotors, calipers.
Note 6: Special 11.75 & 12.19 x .810 inch scallop rotors also available
Note 7: See our rear kits for matching scallop rotors
Note 8: Adds approximately .300" per side track width.