18 replies to this topic

[998dave]

Okay,
I've seen KAD make lightweight aluminium radius arms, about half the weight of standard, but £350

Has anyone tried to, or seen self fabricate readius arms, I was thinking tubular section with inside bored to take roller or plain bearings, and then box section back to another piece of tubular steel for the rear.

Obviously the joints would be seam welded and strengthened/braced, and then threaded holes added to bolt bits and pieces to, (hand brake quadrants and the like.

I'm sure it could be made much lighter then the standard parts, as the radius arms are much heavier then the subframe.
Advantages would be huge with a beam axle and box section radius arms?

Dave

[maph2]

i have some lightweight radius arms, in steel, not homebrew jobbies. were bought in a job lot of stuff. made by a small engineering/motorsport company in london (dunno name)somewhere that had a sideline interest in minis IIRC

[998dave]

That's just what i meant.

Any more pics, or anything with them not in the car. And do you know how much they weigh?

I was thinking it must be easy to make a jig using standard items, and then weld a few bits of tubular steel together.

Makes me wonder why the original fitment are big cast items.

Dave

[maph2]

IIRC about 1/2 the weight of standard arms - straight swap

[998dave]

I assume you then have to fit coil over shock absorbers as you have a beam axle.
(I'm trying to work out what to do with the Hornet).

My thinking is rear subframe's aren't that heavy once the radius arms are off, so surely they're the better thing to change or lighten, especially as they're 'unsprung'.

Dave

[maph2]

I assume you then have to fit coil over shock absorbers as you have a beam axle.
(I'm trying to work out what to do with the Hornet).

My thinking is rear subframe's aren't that heavy once the radius arms are off, so surely they're the better thing to change or lighten, especially as they're 'unsprung'.

Dave

yup have coilovers all round but those arms would go with a standard suspension set up if you could fab up a cone knuckle/rad arm thingy otherwise coilover only

Edited by maph2, 26 September 2008 - 12:20 PM.

[998dave]

Simply keep the front part with the bearings and knuckle connectors, and then cut off the arm and hub, and replace these with box and tube.

This is getting to sound like more and more work... Might start with standard parts, and use the dead subframe and radius arms to work out what's possible.

Dave

[Ethel]

The way to go would be to build a jig around the existing arm assembly. Rose joints would be easier than using the swivel pin. Z cars produce fabricated suspension parts and investigating some Trailer suspensions may be worth while.

[maph2]

suppose it depends what you are going to do with the hronet generally. i'm only usingt the lightweight arms because i had them. otherwise would use standard ones.

i would only bother if you were going to ditch rear frame, cut back rear seat, move battery (i am ), lightweight drums etc

for the cost, effort and general faffing, i'd be inclined to spend the money on fuel injecting the hornet - more economy, more power and torque

[998dave]

suppose it depends what you are going to do with the hronet generally. i'm only usingt the lightweight arms because i had them. otherwise would use standard ones.

i would only bother if you were going to ditch rear frame, cut back rear seat, move battery (i am ), lightweight drums etc

for the cost, effort and general faffing, i'd be inclined to spend the money on fuel injecting the hornet - more economy, more power and torque

Already got an MG engine, and planning on some form of forced air induction, but we shall see...
Maybe fuel injection, I wonder what SPi/MPi parts I'd need... I hadn't thought of that...

[alexcrosse]

http://www.foxwebsit...gn.co.uk/4.html

force racing do some yummy titanium ones

[Tomf]

For the effort i would really concider saving up a and buying the KAD arms, i saw them at combe and my god they are soo sooo much lighter than the standard arms, but then yes as you say they are a hell of alot of money for depending on its intended use not a huge gain...

[998dave]

Those force ones are £800 each! I think that'd be a bit much.

May stick with standard for the moment, and consider upgrading at a later date...

Will still have to take a look at how hard it would be to fabricate my own tubular jobbies. I'll have to take some measurements then get busy with Solidworks... And then try to find someone who'll make them for a small enough amount of money and produce a limited run... Hmmm...

Any other ideas?

[GraemeC]

John from SC Components was devolping tubular steel ones before he started knocking out billet alloy ones - he might be worth chatting to for design ideas etc?

[minivanman]

Simply keep the front part with the bearings and knuckle connectors, and then cut off the arm and hub, and replace these with box and tube.

That would mean having to weld the cast iron though - nearly impossible to do without specialist gear so that its strong enough to take the forces that'll get thrown at it.