Mustang Wheels on Challenger please help

[mopar70]

I picked up a set of Foose Nitrous rims off a mustang with 5x4.5 bolt pattern. The wheels bolt up but hit the leaf springs what size spacer should I use in the front and back. The current tires are 245/45/17 and I might run 275/40/17 in the back.

 

[moparleo]

You need to measure the backspace on your rims first. Also the rim widths. Once you have this information it is much easier to calculate clearances. You might want to contact the wheel distributor who handles these rims and tell them what you are working with. They have all the info needed for any application.

 

[mopar70]

17x8.5 with 4.5" Backspace. Does this help?

 

[74 challenger]

ask CHYRCO he might be able to tell you.

 

[71solo2challenger]

You should be pretty close to fitting already. 17x8.5 should be 4.75" for optimal fit. That being said you should have no problems with 4.5" backspacing as my 8" wide rims have that and my 9" wide rims have 5" backspace. That 17x8.5 with 4.5 is within both of those extremes, front and back.

However reading your post, you should remeasure your backspace or look onto the rim what the offset is (usually in mm). Rims/tires start rubbing at 5.5" backspace.

 

[Chryco Psycho]

too many variables , when the rim is against the spring what is the distance to the axle & body ?

 

[moparleo]

back space

View attachment 10207

Using a straight edge of some sort or level preferably measure the distance from the face of the drum to the inner edge of the spring. Also measure the distance from the drum face to the inner edge of the fender. That will tell you how much backspace you have and the maximum total tire tread width space there is. Remember that when you turn, the tire will move side to side depending on the aspect ratio of the tire ( 40,50 or 60 series) , air pressure in the tire and cornering speed. In other words you will need more clearance when turning than when going straight ahead. It is always easier to visualize a picture than just words. I think there is a cliche about this. To measure the backspace of the rim, place the rim face up on a straight, flat surface like your garage floor and then useing a ruler or tape measure, put the tape into the hole and measure the distance from the ground to the back surface of the rim.

 

[71solo2challenger]

The biggest problem is his backspace measurement is wrong. SN95 (94-04) Mustangs are at about 1" pos offset. (~25mm) The new ones not sure, but I know they have more positive offset. My 17x9s have 6" backspace without spacers and the 17x8s are 5.75". My 1" spacers make both fit.

 

[gafletch]

moparleo, once we have the two dimensions in picture, how do we figure the offset and what wheel to get? thanks. greg

 

[moparleo]

Those are your numbers. With those in hand you will know what the max rim width and max tire width you can go. You now have to choose what rim diameter you want to go with (15" 16" 17" 18" ) , tire width in inches you want to go and tire diameter you want ( this will act like a rearend gear change ). If you have a large tier & wheel store in your area, take your measurements with you and pick their brain. They will have the tire , wheel charts that will take you to the next level. Also you can contact any wheel mfg. Thats how they make their money, and should be happy to help you.