Rear End Lengths

[63BlueMGB]

New to the forum but have been following this forum and others for quite some time. I have researced the how to's alot and have recieved alot of info. I plan on putting fender flares on my car however, I have a complete rear end from 99 mustang GT which measures about 59 7/8, caliper to calipe is about 62, I feel this is much to wide, So my question is what is the maximum length of a rear end you could put under the MGB and what is the best possible ford vehicle I could pull one from that has posi. I was thinking one from a explorer. But I am wanting some opinions.  I welcome any and all responses. Thank you all to whom resond

[Bill Young]

Usually the width of the rear axle is determined by the tires and wheels you are planning to use.  Most builders want similar or the same style wheels both front and rear so pick a style that will work on the front where there is no adjustment for width and then you can determine what the best width for the rear axle would be. It could vary as much as three or four inches depending on the wheel offset and the tire size used. Finding a stock width rear axle that will fit without narrowing is tough. The Dana unit from the old Post Office Jeeps is about the closest and has been used on a lot of early conversions, but later conversions are using other axles and having them narrowed to fit. The Ford 8.8" is popular these days for it's strength and a multitude of different installations making it easy to source from the salvage yard. The same goes for the Chevy 7 1/2" or 10 bolt rear such as found in the Camaro and S10 trucks. Seeing as you already have the Mustang unit I'd suggest just having that housing and axles narrowed to fit after you determine the width you want based on your tire and wheel selection.
If you have followed the Project Roadmaster thread the subject of  how to determine rear axle width came up there a few years ago, go back and look through those messages, should be around page 25 or so if I remember correctly.
Don't know where you are located, but here in the KC area I started asking around among the street rodders and dirt track racers and had a machine shop recommended that narrowed my 10 bolt rear and resplined the axles for less than the well know national shops such as Currie Enterprises charged and I didn't have any shipping charges as well.

[63BlueMGB]

Thanks for the info Bill,  I am actually located in KC also!  I was just thinking about how to match up the front to the rear as well, so that helps out alot. I know that I am going to switch to a Ford bolt pattern front and back since I already have the tires and wheels. So I think it would be wise for me to due the front first and then measure and have my rear end shortened or find one that is close. Do you recommend any machine shops in the KC area that would shorten a rear end. Thanks

[Bill Young]

In the front it's generally better to use a different hub, either a conversion from another car such as used on the MGB Roadmaster or a custom hub such as the ones sold by Bill Guzman at Classic Conversion Engineering. There's not much meat in the original hubs for a 5 lug pattern even in the rather small Ford size that won't conflict with the original 4 lug pattern and have good support on the flange. Bill has hubs for the stock rotors as well as some for larger Wilwood rotors and calipers.
Once you get the front tires and wheels mounted you can measure the tread width and then measure for the rear axle width that will match things up and give you the best clearance in the wheel wells.
I'd recommend contacting Layne Machine Works here in KC to narrow the housing and respline the axles if possible. I say "if possible", as some axles taper down a bit just past the inner splines and depending on how much you are removing from them may not have enough material left in the new spline area to machine. In that case you'll need to buy custom axles from some place like Currie Enterprises or a similar supplier.  Currie makes what they call a cut to fit axle that has longer than usual splines on the inner end so that you can cut them to the length you need yourself with a cut off wheel.

[rficalora]

Having been through this like others, I'd recommend not being in too big of a hurry to get the rear end narrowed.  Especially since you already have your wheels/tires -- set the car up @ ride height, get your flares tacked on to where the tires clear through the range of compression & then measure from wheel mounting surface to wheel mounting surface.  That'll tell you how wide you want the rear end.  If you think you might want wider tires at some point you'd go deeper to the inboard side so if that's a consideration, you could get the rear done a little narrower & run spacers -- but probably don't want spacers more than about 1/4" to 3/8" per side unless you go to the type that bolt to the hub & have seperate lugs that bolt to the wheels.

[tr8todd]

One thing to remember.  Most car based Ford axles will have the center of the pumpkin offset about one inch.  The truck/Explorer axles will be offset about 3 inches.  Just a generality, but something to consider.  You can look at an axle length chart and you will see that most trucks come with two different length axles.  I used an Explorer in one of my TR8s by shortening the long side and using two short axles.  It ended up real close to the stock TR8 axle length.  Something like 3/8" shorter.

[BlownMGB-V8]

Front hubs. Ford pattern hubs aren't real common since the aftermarket quit making 2 piece hub/rotor sets. Might want to get that squared away before messing with the rear.

JB

[roverman]

One more time,series II Mazda RX 7,(owned by Ford). Strong aluminum hub with 5 on 41/2" bc. Possibly bush the hub to use your MGB bearing cups. Good Luck, roverman.

[Bill Young]

Art,is that a conversion that's been fitted and all the kinks worked out or just something that looks like it might fit? Just curious about options for the stock MG front spindles.

[mgb260]

Also, My conversion, using readily available 65-66 V8 Mustang hubs,Dodge Intrepid rotors(11.1 for 15",11.7 for 16-17" wheels,Toyota T100 4 piston calipers. The hubs can be bought new for around $ 70 each in Mustang restoration catalogs. I found a used pair on car-parts.com wrecking yard search for $25 each. You could cut the existing rotor off on the relacement one piece unit like the Camaro version in the 5 lug brake thread. David Townsend is putting them on his MGB. He has a forthcoming article on the swap, kind of a how it was done. 83-92 Ford Ranger 7.5", 90-92 8.8". Use 2 short side axles, shorten longer tube, only 1' wider than MGB. If you do the small bearing 9"ends can probably be shortend a little more and do away with C clips. The Ranger axles have to be turned slightly for the press on bearings,and cut off the C clip button on the ends.

[roverman]

Bill and clan, as of this date I've converted these for Mustang II spindles,(Wilwood). Series II RX 7 spindle dia's are larger yet, at 1.375 and .787". The rotors have been discussed earlier, in this forum. I haven't compared to MGB spindle, but "might" be worth a look ?  Good Luck, roverman.