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MG MGB GT V8 Factory Originals Technical - RV8 Tapered Leaf Springs on an MGB?
|What modifications, if any, are necessary to mount a pair of tapered leaf springs from the MG RV8 onto an MGB? Does anyone out there have personal experience with this conversion? I'm led to believe that this will improve both the ride and the handling.|
|May need the RV8s axle location mods as well.|
I have fitted a pair of RV8 springs to my GTV8 conversion.
You can see pictures of this at;
They will bolt in but require the use of longer shackles on a C/B car.Thus is because the springs are longer behind the axle and the std shackle ends up hard against the chassis leg. The rate is also very high for a roadster at around 185lb/in-this is counteracted by the much softer initial action.
They aren't that cheap since all the surplus ones have been sold off by Brown and Gammons. You may find the Doug Smith ones(www.mgbmga.com) in conjunction with a compliantly mounted pair of tramp bars(compliance is VERY important to allow axle rotation) easier to obtain in the US.
They work quite well with much less of the rough riding feeling of the std V8 springs.
>You may find the Doug Smith ones(www.mgbmga.com) in conjunction with a compliantly mounted pair of tramp bars(compliance is VERY important to allow axle rotation) easier to obtain in the US.
I think it's Doug Jackson, but anyhow ... what do you mean by a compliantly mounted set of traction bars? How far should the axle be allowed to rotate before the tramp bar kicks in? Won't setting them up "loose" i.e. with no preload, absolutely hammer the car into submission? Many thanks for a little more explanation.
Yes you are right I did get the name wrong -up too late...
If you look at my traction bars on the conversions site you can see that I'm using a closed cell foam doughnut type of joint for thr front of the bar.This allows the axle to twist when one wheel goes into bump and droop and also allows the bar to change length with the spring as it flexes. In my opinion if you just use parallel bushes for the bars you end up with the action of the springs being affected by the bars not being able to twist or change length. A lot of my ideas come from the states where the continued use of live axles has led to continuous development with things like traction links that have telescopic shocks and springs built into them,decoupled torque tubes/arms etc.
I don't follow the axle rotation bit ... most people I know use standard rod ends for both ends of the bar ... they are bushed with nylon and allow maybe 15 degrees of rotation. The axle can thus twist when one wheel goes into a bump.
But I think you are really onto something key with respect to allowing the spring to flex freely. Most traction bars do no good at all for the car's handling because they bind the spring rather than allowing it to move freely ... no matter how carefully you measure the front of the spring, since the spring is curved and the traction bar is straight, they move through their respective arcs of motion differently. For this reason, I haven't put traction bars on the car because I haven't seen a good solution. My car has the composite springs and they do wind up and chatter under hard acceleration but this is somewhat mitigated by the fact that I run a Hopkinson rear sway bar clipped in to the spring perch plates (I know from past threads that you would not approve!)
Using your design would probably be great but it is way over my head fabrication wise! Nonetheless, do you have a set of sketches or something to work from? ... I don't really understand how you've got the front of the bars rigged.
|So, am I correct in assuming that these springs are no longer manufactured? Is there no vendor who sells reproductions of them? And what about the longer rear shackle? where can those be obtained?|
I could send you a sketch if I knew your contact address-can you e-mail me offline?
The original RV8 springs were made by Hirsch Woodhead directly for Rover-as far as I can tell they are only availible from Rover main agents spares outlets. Brown and Gammons bought all the factory surplus stock and have long sold out all their springs.
As for the longer shackles-I made these my self-reusing the original pins which are simply pressed in with a shouldered spline fitting similar to that used on a wheel stud(see the V8 conversions site).
This thread was discussed between 13/02/2001 and 12/03/2001
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