Ive been looking around for 9" rear ends for my build if you guys can throw me any expertise. I was thinking about just picking up the one on speedway motors but also had the idea of getting the narrower 64-66 which I've heard will give me more wheel options. Will this work? are the stock leaf mounts in the same spot?
9" Rear Ends
- Thread starter back67fast
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horse sence
15 Year Member
What year Mustang ? The 65 -66 is narrower than a 67 -70 . The 65 -66 width will work in a 67 -70 but that also depends on the back spacing of the wheels you want to use. The spring pads are the same on all 65 -70s ,71-73 is wider than all
In about the narrower axle housing giving more room for fatter tires, I know you said "more options" not more room but that is what you meant right?
The limiting factor of rear tire clearance is the wheel-well itself, two clamshell like parts pinch welded together. Any shorter or longer axle housing can be compensated for with backspacing on new custom wheels or the use of spacers. You'll need major sheetmetal fabrication to increase beyond what will already fit in your stock wheel-well. FWIW --- I think that 245/45-17 on 17X8s fit perfectly on your'67 without the sheetmetal work. I'm running them on a factory 9-inch from a wrecked 1969 428 Cougar.
The limiting factor of rear tire clearance is the wheel-well itself, two clamshell like parts pinch welded together. Any shorter or longer axle housing can be compensated for with backspacing on new custom wheels or the use of spacers. You'll need major sheetmetal fabrication to increase beyond what will already fit in your stock wheel-well. FWIW --- I think that 245/45-17 on 17X8s fit perfectly on your'67 without the sheetmetal work. I'm running them on a factory 9-inch from a wrecked 1969 428 Cougar.
1957 - 1959 Ford station wagons and Rancheros.
I got mine out of a 1957 station wagon.
Just a thought, unless you are putting down a lot of power do you really need a 9 inch? The reason I say that is because I had a 9 inch in my car and the un-sprung weight was too much. The car felt sluggish and slow, I recently switched to an 8.8 and the car seems much more responsive and easier to drive. Just my experience!
horse sence
15 Year Member
Probably your gear ratio ,a higher gear will feel slugish . The standatd ratio is usually around 2:78 that would be great for highway use ,but if you want a more perky fell go with 3:00 or 3:25 for an auto or 3:25 or better yet 3:50 for a manual
Thanks for the input guys, i really need to get on here more. I'm having a 351 cleveland built to a 393 with aluminum heads so i should be at around 400hp possibly more so i think a 9" is justified. I do have a tremec 3550 already and as you mentioned my plan is a 3:50 gear. The rear end is actually a one of the last big puzzle pieces i wanna pull in before i start putting together a suspension and brake package.
I actually just came across one from a 1980 granada and through my research the spring perches match up but the length of the rear end is 58"? would i be able to make this work? Edbert, my reference to more options was in hopes of fitting a 265 tire on the rear as well as getting a bit more lip out of a wheel. I don't mind rolling my fenders to achieve this but is this possible without modifying wheel wells to much?
I actually just came across one from a 1980 granada and through my research the spring perches match up but the length of the rear end is 58"? would i be able to make this work? Edbert, my reference to more options was in hopes of fitting a 265 tire on the rear as well as getting a bit more lip out of a wheel. I don't mind rolling my fenders to achieve this but is this possible without modifying wheel wells to much?
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