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New wheel fitment with disc brake conversion?

Im getting a 69 mach1 with manual 4 wheel drum brakes and will be buying a new set of rims and tires right away. I will be getting the MB wheels old school 17x8 and 17x9.5. I will also be converting it to 4 wheel power disc brakes. What issues would I have fitting these with the new brakes and rotors and what offset should I get?
 
Most disc brake setups won't affect your offset/backspacing requirements.

http://dodgestang.com/ is the place to look at wheel combos.

17x8 & 4.75" BS should fit up front, and the rear will probably need 5.5" BS or better, if I had to guess.
 
I noticed their website doesn't specify if the offset numbers are positive or negative, which really messes things up.

0mm offset is 4.5" BS and +7mm is ~4.70" on an 8" wide rim. -7mm is ~4.125".

+6mm on the 9.5" wide rim is 5.5" BS and -6mm is 5".


+7mm offset on a 17x8 is your best bet, with 17x9.5 with +6mm in the rear, though these wheels might not fit that well, hard to guess without exact backspacing numbers, and/or tire sizes.
 
Thanx for the info and pics, helps a LOT!!! I plan on running 245 or 255/40 on the front and 275/40 on the rear. Any problems with thse tire sizes on a 17" rim?
 
my tire sizes are 235/45 on the front & 285/40 on the rear. the overall diameter of these mounted gives a 1/2" greater height on the rear. i think the 245/45 & 275/40 measure the same overall diameter on these wheel sizes. not sure on the 255/40, but if you go to tirerack.com, they list measurements on all the tires so you can get a good idea there.
 
the 40 & 45 designation shows the sidewall diameter as a percentage of the width of the tire. 45% of 235mm = roughly 105mm. 40% of 285 = 114mm. thats a 9mm difference which is close to the 1/2" rough figure i gave. (13mm is 1/2") . some tires have a true measurement a little larger or smaller than listed so there will be slight variances.
 
Ok, heres the e-mail I got from them:
Thank you for contacting us. This wheel in a 17x8 is available in a 4.5" (0mm offset) or 4.75" (7mm offset) backspace and in the 9.5" it is a 5.5" backspace. Please let us know if we can be of further assistance.

So would these fit and which backspacing for the front should I get?> Also, what tires sizes do you recommend?
 
"panteramatt" said:
Ok, heres the e-mail I got from them:
Thank you for contacting us. This wheel in a 17x8 is available in a 4.5" (0mm offset) or 4.75" (7mm offset) backspace and in the 9.5" it is a 5.5" backspace. Please let us know if we can be of further assistance.

So would these fit and which backspacing for the front should I get?> Also, what tires sizes do you recommend?


I hate to give recommendations on tire sizes/wheel backspacing..... but if it were me, I'd go with the 4.75" BS on the front wheels with a 245/40/17 tire. The rears with their 5.5" BS should be fine and a 275/40/17 tire should fit, but you may end up needing to roll the fender lips.

With 17" wheels you shouldn't have any interference issues with any of the usual disc brake kits.
 
i agree with dave, i would have went with the 4.75" b.s. on my fronts, but centerline only offers 1/2" increments so went with the 4.5" . staying in the 235-245 range on the front & 275-285 on the rear will be fine.
 
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