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MG MGB Technical - wire wheels to alloys

Having now got my garage find on the road I need to think about wheels. I have painted wires at present which need refurbing. I'm no fan of painted wires (should be chrome if wires and budget doesn't stretch to those). I want to convert to alloys so need different hubs. I read an article about using the same rear axle but changing the rear hubs for disc wheel ones but using longer studs and spacers to make up for the difference in axle lengths. Has anyone tried this or should I go for a complete axle change?
Steve Church

Steve-
Yes, such adaptor hubs do exist. What the vendors don't mention in their ads is that they will space your rear wheels out so far that the tires will rub against the inner fender if you corner with any enthusiasm unless you add a Panhard Rod in order to limit rear axle sway. A complete rear axle change is the better way to go.
Stephen Strange

Steve,
These are not adaptor hubs. These are ordinary steel wheel hubs taken fron a steel wheel axle. I believe the wire wheel axle is shorter than the steel wheel axle so the hubs would place the wheels too far inboard thus needing spacers to move the wheels outward. Converting steel wheels to wires would have the effect you mention.
Steve Church

I think a steel-wheel axle would be the best option.
Dave O'Neill 2

Axle width is only an issue if changing between standard hubs *and* wheels. If fitting non-standard alloys to standard (or indeed any) hubs surely the offset can be selected to get the correct spacing in the arch.
PaulH Solihull

Steve-
Sorry, I should have read your original posting more carefully. Which rear axle are you working with, a Salisbury tube-type or a Hardy-Spicer banjo type?
Stephen Strange

Paul, an interesting solution perhaps but could be a problem finding wheels with the correct offset.

Steve, I have a Salisbury tube-type axle. The car was originally a '68 GT (now reshelled as a roadster).
Steve Church

Steve I have been using Superlite knock on alloys for a few years now and am happy with them. They fit straight on and are available in 14" - 15" You can get other makes as well. See photo. Denia

Denis4

Just as a matter of interest, does anyone know what the offset is for standard MGB 14 inch Rostyle wheels?
C.S. Barrow.

It's quoted in various places as 22mm, but I have measured my Rostyles at 27mm positive, using what I understand as the standard method which is the distance between the centre of the wheel and the face that contacts the hub or drum, and positive where that face is further out from the side of the car than the centre of the wheel.
PaulH Solihull

Hi Paul, Many thanks, your interpretation of offset is the same as mine.
C.S. Barrow.

If anyone wants to measure their own offset then
don't forget that the width of the wheel is measured from the inside of the rims. Each rim is about half an inch thick. So a 5 inch wheel is in fact 6 inches, from the outside edges of the rims. That is the cause of much confusion. Adding to this Backspacing is another method of measurement. The backspacing is measured from the bolt up face to the outside of the rim. Usually by placing a straight edge across the rims, side to side, and measuring distance down to the bolt up face. This is where the half inch rim thickness needs to be taken into account. It doesn't help that offset (as defined by Paul above) is measured in millimetres.
Peter Sherman

Surely where you measure from is irrelevant as long as you measure from the same point both sides to find the centre of the wheel? The offset is measured from that to the mounting face, not from the edge of the wheel.
PaulH Solihull

This thread was discussed between 30/10/2010 and 07/11/2010

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