What involved in narrowing a rear end?

Narrowing your rear end to make those rims fit would not be cost effective. Even if you did all the work ourself it would cost more in time, materials and parts to narrow the rear than it would to buy rims with the correct spacing.

To narrow the rear a little is easy, they cut off the flanges, take out a chunck of tube and put the flanges back on. But to narrow it much will require the perches to be moved inboard for tire/wheel clearance, again that part is easy but the car will need to have the rails modified accordingly. If you need to do that you should look into another spring option.

yup..depending on how much, you need to cut the axle tubes, possibly the perches, re-weld it all then, new axles

what year mustang do you have ... 67?

if you have a stock 8" 1967 and want to swap one from a 66 the rims would fit. a 66 rearend is 1 3/4" shorter total than a 67 rearend.

you even need to run a 1/4" spacer on those rims if you do this swap


hope this helps

What involved in narrowing a rear end?

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Thighmaster and Atkins diet.

hum, now i got a question, if you put a 66 9" in a 67 what is required? do I need to move the spring mounts? I was thinking of trying to get a narrowed rear end so I can get a bit beefier tires under the back and a minitub. I would rather just get a 9" for a 66 and gain almost an inch width on each side. That would save me time and money over a tub and shortening.

It's not that hard to do on the cheap. The '65-'66 housing is a good idea though. Narrowing your housing that much won't require moving the perches.

Okay, first pull your axles out. When you look at the splines on the end, there will be a line that goes around the diameter, this is where the spline engages the center section of the third member. Measure how much spline is left outside of this line, meaning how much spline is left towards the wheel flange end of the axle. If you have over 1/2" to the point where the bottom of the spline starts to taper out, your good. If not, you'll likely need new axles, the aforementioned '65-'66 axles would work, but if it's just a bit, patience and a steady hand with a cutoff wheel, you can lengthen these splines a bit. If you have 400+HP potential, I'd recommend new axles, Moser is a good place to get them.

Next, pull the center section out and put each axle back into it's appropriate side of the center section to the previous mentioned line around the splines. See how much you can slide each side further into the center section. If you can bottom them out, your in good shape. If you can't, but have plenty of spline left as in the first point, you can cut a bit of the end of the axle off with a metal chop saw and bevel the end back with an angle grinder. Then take a triangle file and clean up the ends of the splines.

Third, to narrow the housing, you cut the ends off with a band saw and can either cut it again for the 1/2" or so, or just cut it once at the correct length and take the 1/2" off the housing end in a mill. You need to take the housing to a place that can properly narrow it to begin with, they'd do these operations for you. Once the pieces are at the right length, they taper the ends to be welded then they put in a third member that has bushings for a lineup bar, they put bushings in the housing ends and slide then onto the lineup bar and this makes sure everything is perfectly lined up and parallel and the ends flanges are perpendicular.

To narrow your housing will typically run about $100-$125. If you don't have to modify your axles, all your out is some brake fluid and some rear end grease and a gasket.

If I were going to buy new axles AND narrow a housing, I'd go ahead and upgrade to a 9" and do 31 spline axles and a locker.

hum, now i got a question, if you put a 66 9" in a 67 what is required? do I need to move the spring mounts? I was thinking of trying to get a narrowed rear end so I can get a bit beefier tires under the back and a minitub. I would rather just get a 9" for a 66 and gain almost an inch width on each side. That would save me time and money over a tub and shortening.

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Note 12SEC67 was speaking of an 8" rearend from a 66 to a 67. A 9" from a 66 will be almost impossible to find. To get the short 9" you would need to find a mid 50's Ford passanger car. This option only costs slightly less that having a rear end shortened, and depending on the tires still will not get around tubbing.

yeah, i saw the other thread that was started on axle swaps. The spring perches are at the same position so it doesn't gain me any clearance from the springs. Only thing the shorter axles gives is less rotational mass (ever so minimal) and different backspacing. bah.

And currie has a housing and axles for like $950 add brake and it is $1375 that is a direct fit for 65-70 mustangs

Moser

Moser charged me $110 to narrow an 8.8 housing last summer. The new axles were $235 for the pair. I think the charge for the narrowing would be the same, but the axles might be a different price for a 9". You have to completely strip the housing (you can leave the pinion gear) and ship it to them. Kind of a pain!

Call Currie Enterprises.

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