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MG MGB GT V8 Factory Originals Technical - IRS selection for a MGB
I want to swap an IRS for a MGB and I have some hesitations. First one is an IRS from a Datsun 510 (R:3.89), which seems the easiest route as bolt pattern is the same than MGB. The second is from an Opel GT (R: 3.44) but with a bolt pattern is 100 mm.
For both track is in the 50"(+/-0.5") wide.
Any suggestion and advice on relaibility are welcome...
|Jean Guy Catford|
|Can't help you with reliability. I can tell you that there are many, many more wheel choices with the 4X100mm bolt pattern.|
Yes indeed there is a lot, but offset is a matter of consideration, as FWD are mainly positive. But the basic problem is for a MGB with 4.5" bolts pattern for front and 100 mm at rear.
|Jean Guy Catford|
You're comfortable completely replacing the entire rear suspension on your car, but you're not comfortable changing the spacing of lugs on two hubs and perhaps two brake rotors (or drums)?
in the 80's, there were Mitsubishi two litre automatc cars on the European market, named Galant.
Only the automatic gearbox version has had this IRS setup (while the same model with 5 speed box used an insallatin comparable to the Sailsbury, but with coil springs).
These were fitted with a IRS and had the 114.3 diam. 4-bolt and rear discs.
Dont know whether someone has tried to put this under a MG B jet, but I try to spot one of these cars to check it.
May be these Mitsubishi Galant Automatic cars are also found in Canada or in the USA and someone can give further hints.
Keep us posted!
|jean, see the nearby thread on datsun IRS.|
Track is apparently 4 inches wider and the UV joints are't very strong.
|Jean, as far as I know there is nothing available from existing cars that will fit without a lot of modification. Most are simply too wide for a B. OK, you have to modify, so select components which have the strength necessary and a variety of ratios available. The later model Ford IRS used on T birds and Mustangs is based on the Ford 8.8" rear and should have a variety of ratios avaialble. It's also strong enough for a V8. Other options would be from a lot of the smaller SUVs. You'll probably have to have half shafts built to size as well as fabricate all the linkage and A arms. If you're going to design one, try to use the original suspension pick up points on the B chassis, that way you could design a kit that would be a bolt in for other B's, might help others and defray some of your expense.|
You could source all your linkages, wishbones hubs brakes (all the moving bits!) from something else and make up just the diff' cage for these (and the diff')to bolt to. This is just a square frame after all. You might even get lucky and find some drive shafts to fit. For example off the front of a 4WD. The diff'/gearbox is often wider than the rear diff' so the shafts are shorter at the front. Odds on the front and rear are splined the same, so use front shafts on rear diff' Possibly subaru.
In the thread on datsun IRS there is an interesting post about Nissan diff and drive shafts fitting straight in.
|Just had a close look at Gregs post. The rear suspension on that looks remarkably like a front suspension, turned around backwards. The steering arms are being used to alighn the wheels. That certainly opens up a few possibilities. There are plenty of front wheel drives around with nice short drive shalfs,of a variety of lengths.|
|you can use an early Jag XKE IRS...if you can find one. the cage will bolt into the MGB bodyshell with out mods...depending upon whether it is a rubber or chrome bumper model. If mods are needed, it is to the battery box.If you use wheel well flares no narrowing is necessary. If stock wheel wells are utilized then the lower control arms and axles need to be shortened 1.25 inches. The bolts pattern is MGC or can be changed to match the front.|
|Peter, the Solstice is a result of "parts bin" engineering at GM. They may have used existing suspension parts to come up that rear end. I believe the rear is also shared by the Cadillac CTS.|
The solstice is an idea but find it in a yard is a rarity for the time being. I will explore the Subaru route. But a 510 is still acceptable if I could replace original half-shaft with weak U-joint by C.V. type half shaft.
I have in mind adjustable coil over shock in that set-up.
|Jean Guy Catford|
|Well, they are around:|
This thread was discussed between 13/06/2006 and 17/06/2006
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