Technical Narrowing a Ford 9" rear end

I have a Ford 9" complete rear rear end I picked up to put in my roadster, but would like to narrow it a little bit, just an inch or so on each side. Can I use the stock axles? I know I can cut some off the spline end if necessary, but the question is how much "cheating room" is there on the splines? Are the splines longer than necessary?
Thanks

 

Look at the splines on the axle and they will tell you what you need to know.

 

You can use the shorter axle from another rear and you will be 2 1/2 " shorter just cut 2 1/2 from long side......

 

Tapered axles can't be shortened, others can provided they don't step down. 28 or 31 spline?

 

If you only cut off 1" you will be in an area of the axle that will not be big enough for new spline. You would have to cut off a fair amount to reuse the same spline count. OR, If your pumpkin has 28 splines, you could find some 31 spines axles and have them cut to 28 at what ever length you need.

 

Depending on the budget, time. Ford produced many widths of 9" axles. A short and a long one in most all examples. You can find another axle and shorten one side of the housing as previously stated.

I built a jig back in the eighties and have shortened/built more than several rears.

I have used these axles with no problems. Shorten housing on one side and cut one of these axles. Lots of spline on these. My gasser project has two of these type axles, in bigger spline.

http://www.ebay.com/itm/9-Ford-28-S...yle-/221643046281?vxp=mtr&hash=item339af47d89

His rear end ruler is a great tool.

 

I had a Galaxie axles shortened to suit a 56 1/2 diff, done by swapping the short axle to being the long. Then just one axle needs to be shortened.
This went into a cutdown F100 housing

 

Your question is a little vague. When you say "cheating room", are you saying you just want to narrow your existing axles and not re- splining them and only using the shortened splines? If so don't do it. Narrow the rear and get the proper axles!

 

You can "cheat" but only by 1/2 inch each side, most axles have at least a extra 1/2" that don't engage the spider gears. A lot of work shortening a housing a 1/2 inch each side to get around getting a axle resplined.
I'm a cheap ass, best and cheapest option is (IMP) swapping the long for short and only only getting one axle resplined.

 

One thing about shortening diffs and axles, just try and keep the "pumpkin" in the centre.
Nothing looks more wrong especially in a spring over than a diff centre housing (pumpkin) sitting offset looking from the back.
The spring in a perfect arch over the diff but with a off centre housing just looks wrong (In my opinion after a few drinks of good Scotch)

 

Thanks for all the info fellas