Question about rim/rearend width

[1sick65]

Question about rim/rearend width (PICS)

I have a 65 mustang with a stock 8 inch rearend, i believe it is 57 and 1/4 inches wide... Now i have a set of rims that are 17x10 with a +20mm offset. I have already removed the inner wheel well so i will have no interference there. my question is will i have to narrow the rear for these tires to sit inside the quarters. thanks Nick

 

[ron67fb]

Wheel Offset Calculator

 

[coolblue65]

Your problem will more then likely be the tire/wheel hitting the leaf spring. Below are a couple pics of me trying to stuff 275 drag radials under my '65 -these were on 15x8 rims with a 4.75" BS. Notice the tire itself is hitting the leaf spring and is sticking out past the fendor. A 17x10 is a big wheel, and I think the only way it will really work for you is if you flare your fendors or change your suspension.

 

[1sick65]

ok heres what the inside of my car looks like... a little different then i think you were expecting

 

[ron67fb]

FYI 15" torque thrusts for early Mustangs use from +4mm to +6mm offset, so start with that. 14" used negative offset, about -2mm.

 

[ultrastang]

I see by the photo, in link below, that your car's 8-inch rear has the old style weaker '62-'66 8-inch 3rd member, as evidenced by the lack of additional ribs you would find on the face of the '67-'80 model 8-inch 3rd members.

http://i51.photobucket.com/albums/f400/nicktomstew/untitled4.jpg

Having that much tire [surface area] in contact with the pavement with that 3rd member stands a good chance of tearing the driving pinion out of the case.

If you don't install an 9-inch, I would at least suggest installing the stronger C70W-style 8-inch 3rd member in the rear end you have.

 

[1sick65]

thanks, i think i am just gonna order a custom width fab9 to ensure proper wheel fitment. I am still having trouble figuring out this backspacing concept any more help would be appreciated

 

[ron67fb]

I am still having trouble figuring out this backspacing concept any more help would be appreciated

What part do you need help on?

 

[thekid760]

https://www.rsracing.com/tech-wheel.html