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MGB Modifying an MGB Differential

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Assuming that Tony, our resident Gentleman Farmer, has time to look into the "upward slop factor", I do love those technical terms, I will go ahead and try to describe my thought on the housing modification. Actually there are several. The heat and bend routine, visions of Reece Witherspoon in Legally Blond come to mind, might be the simplest but I could see where someone with great knowledge of torchology would be needed along with someone who could make up a comparative jig to insure accuracy. Obviously this would best be done on a full banjo unit as the bending would have to be done as closely as possible to the outboard plane of the carrier bearing. The inside cavity of the axle shell should be large enough to accommodate the repositioning of the shaft inside. This would end up being the least detectable route for scrutineering, not that one would deliberately bend the rules. Another method would be more involved in the engineering and machine work departments and certainly be obvious to even the local oil change guy, but it would also look like one of the high tech machinist detail oriented fanatics on this list had done it. It would involve removing all or a portion of the tube from the center section of a Salisbury axle and grafting it to a prepared banjo pumpkin. I have not looked too closely at a Salisbury axle with the intention of removing the tube whole from the center but it might be possible given enough heat and weld removing expertise. Cut the weld away, heat the joint and slide the tube out. The advantage of this would be to maintain as much of the tube length as possible and thereby make it possible to make the grafting joint as close to the banjo carrier bearing as possible. An alternative would be to slice the tube at it's junction with the Salisbury center section. If this were done the tube would have to have a length of like material grafted to it to bring the inner tube opening closer to the differential. In any event the joint would be made by fabricating a flange pair that would be welded each half to the tube and the cut banjo diff. The secret would be to have the working face of the banjo perfectly vertical and the working face of the flange attached to the tube machined at precisely 1.5 degrees off of vertical. I see a six bolt round flange of sufficient thickness so as to avoid any chance of failure at this joint. This might look a little like a fire hydrant but it would work. And all of this just to make a LBC go around a corner just a little faster. Oh my! Jack
 
I'm visualisin' the "fire hydrant" effect, and concluding the weight would be *increased* withthe mod... I kinda think Tony's First Priority was reducing unsprung weight?

Tho: "...but it would also look like one of the high tech machinist detail oriented fanatics on this list had done it." has tremendous appeal, y'know. meh-heh.
 
If you're just running autocross, it'd be way easier to just have the Hoosiers shaved on an angle.
Would give the same "negative camber affect" in the short term.
NASCAR guys used the negative-camber, live-axle rears for a while, but I think that's outlawed now.
 
The following assumes the late model salisbury axles have the bearing pressed onto the axle and this assembly is inserted into the tube of the housing. To achieve 1.5 degrees of negative chamber at both wheels you will need to lower the point of intersection of the axles, if they were extended to the center of the rear end, .4713", per an AutoCAD layout based on the 36" dimension, between bearings, of my TR3. The closer to the center of the car that you splice the replacement axle housngs to the original center section results in the least change of angle and least obvious change on the housing that you need to achieve. If you post the dimensions of the proposed cuts and the axle bearing locations I'll CAD it up for you!

How do you insert pictures?

If the salisbury bearings are pressed onto the tube of the axle housing and a hub is attached to the bearings.

If there are two bearings spaced apart than cut the tube of the housing as close to the outbaord end as possible and weld the salisbury bearing end at a 1.5 degree angle.

If there is only one bearing than angling the end of the salisbury bearing end will have to be welded on at a greater angle and severly increased bearing wear will occur.

If available using replacement locking spider gears will result in a stronger locked chunk over one with the gears that the axles slid into welded, heat effects. This also allows the gears to move around and that up some of the angular misalignment. An alternative would be to weld the idler spider gears to the housing.
 
I'm a Tar Heel and know that a Hoosier is either a person living north of Vrginia or a cabinet used in a kitchen. How does either relate an MG axle? And on what surface would one machine a Hoosier? :smile: How 'bout them Apps! National Champs for the first time! Jack
 
He means Hoosier tires /ubbthreads/images/graemlins/smile.gif Other brands include Kumho's, Yokohama's, and perhaps a few others that produce a suitably sized R Compound tire.
 
WOW! All I wanted to do was reduce unsprung weight; but, some thoughts...

Jack: you may be onto something....however, the way the banjo differential is made is kinda like an 'extrusion'..there's no way to insert the Salisbury axle tubes...& one thing that allows the banjo its strength while keeping weight down is the way the center section 'blends' (for lack of a better word) into the tubes.....were I to try to bend the tubes, I'd have to do it way on the outboad ends

...there's the problem: the third member (somebody on the other BBS chastised me for calling it a 'chunk' - ****, people can get a bit pissy, can't they?)bolts to the banjo differential & would not turn properly, I think, if the axle was inserted at an angle that would be necessary to get the negative camber...

....additionally, the bearing is pressed onto the end of the axle & to get it to fit properly in its carrier which is the end of the axle tube, I think I would have to weld the end of the Salisbury (tube) axle tube that has the bearing carrier on it onto the banjo case at an angle

...all of that just seem beyond my machine/fabrication skills, I'll admit!

WOW, again - this thread has been a real learning experience.
 
Okay Tony, I know that his thread is sort of petering out but I am not going to forget it. When the holidays are over and I have a breather after my early year shows I am going to do some hands on testing of my ideas. In the mean time if you come across a trashed axle of either or both types don't send them to the scrapper, if I can't find them up here I'll come down and swipe'em for the common good. I'll let you know what happens. And for that matter, if anyone else up in my direction (northwest corner of NC) finds some axle shells let me know and I'll pick them up. Jack
 
Will do, Jack...today I've been playing with leaf springs! & making some 5/16" thick lowering blocks.
 
Jack, I have a banjo axle housing or two you can have for free if you'll pick the darn things up.
 
James - do you also have the u bolts, bump stop & lower spring plate setup for a banjo rear end...everythnig to bolt banjo to springs?
 
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