maximizing tire sizing on a 67 mustang

[danibug]

Who out there knows FOR SURE exactly how much tire will fit on the rear of a 67 Mustang Fastback and stock 9" Ford rear? I've finally decided to run 17 X 8 with 245 up front. I know it fits. My math suggests I "could" run as much as a 275 on the rear with a 17 X 9.5 rim but I don't trust my math! Rolling the lip is NOT an option because the paint is done. I've got Global West leafs - sits perfect, no lowering blocks etc. so my guess is I "might" have a clearance issue with the leafs before any problem with the inner well. So, who has actually put larger than 245 on a 17 inch rim on the stock rear wheel well? What offset etc.??? Please no guesses, I'm already there!
Thanks in advance.

 

[bikefreak600]

dont know if it helps, but many people chimed in here
http://www.stangnet.com/mustang-forums/840735-rear-suspension-mods-big-wheels.html

 

[dodgestang]

Who out there knows FOR SURE exactly how much tire will fit on the rear of a 67 Mustang Fastback and stock 9" Ford rear? I've finally decided to run 17 X 8 with 245 up front. I know it fits. My math suggests I "could" run as much as a 275 on the rear with a 17 X 9.5 rim but I don't trust my math! Rolling the lip is NOT an option because the paint is done. I've got Global West leafs - sits perfect, no lowering blocks etc. so my guess is I "might" have a clearance issue with the leafs before any problem with the inner well. So, who has actually put larger than 245 on a 17 inch rim on the stock rear wheel well? What offset etc.??? Please no guesses, I'm already there!
Thanks in advance.

I know because i run 275 rear.

I also have a chart that knows....because it isn't a rule of thumb chart it is a chart of what people have on their cars that I used to buy my 'safe' fit 275 conbination with custom wheels because I didn't want to push it with 315s .
Dodgestang Photo Archives

 

[67GTFB]

like Dodgestang sez (nice looking ride btw!) .... what also matters here is the backspace or offset for those rear wheels ..... didn't see those figures in this thread (yet) ....

 

[danibug]

I'm new to this, so I hope my reply is done correctly. Thanks for the valuable information. Like 67GTFB brought up is, what backspace did you use. The fit of the 275 looks perfect but rim size and backspace is what I need to know. Do you have that info? Thanks again for all the great comments.
If I accidentally send this to the wrong place, I'll try again to get it right.

 

[dodgestang]

Line 55 (3rd from the bottom) on the 67/8 tire chart; link previously provided but here it is again (what someone other than me is running)
http://www.dodgestang.com/emAlbum/a...e and Wheel Chart/Tire Fitment Guide 67-8.pdf

235 45 17 and 275 40 17 17x8 4.75 and 17x9.5 and 5.5 is what I am running.

 

[danibug]

Great chart, sorry I missed it the first time. Thanks!!!