Converting uprights to ball joints ?

[paulhumphries]

In theory I can work out a method of converting the lower trunion to a ball joint (no welding or machining of upright other than cutting thread down to shorter length).
Anyone ever seen this done ?
PLEASE don't say anything like "leave standard", "there is nothing wrong with standard set up", etc as that isn't my question
I can understand why there might not be a commercial conversion kit due to the potential liabilty aspect.

Thanks.

Paul Humphries

[bmcecosse]

The lower trunnion gives stiffness in the n-s direction, only allowing rotational movement - but I suppose it could be changed to a ball if you have a way of connectiong it to the leg - but I have to ask WHY ? Are you going for McPherson strut suspension ?

[paulhumphries]

but I have to ask WHY ? Are you going for McPherson strut suspension ?

I'm not feeling well (normal for me) so am sitting here dreaming up ideas.
That dosen't mean I'll actually do anything but like the mental exercise of trying to work out solutions.
I love my Minor and wish I'd "discovered" them years ago.
There are various aspects that I'm not 100% happy with but they are common ones and easilly sorted (disc brakes, servo, inertia seat belts, no temp guage, under floor brake reservoir etc).
One thing that niggles me is having to remove the wheel to grease the suspension hence my mind thinking of how I'd prefer it to be - maintenance free ball joints .

Paul Humphries.

[bmcecosse]

Might be easier to fit greasing tubes to the grease points - and run them up to where they can be reached without removing the wheel! Alternatively - fit a full remote oiling system to grease all the points with the pull of one lever. Might be tricky doing the prop shaft !!

[Packedup]

I've seen pics of the lower trunion on a Spitfire being converted to balljoint - Apparently it's a Caterham design. I can't remember what the upper joint is on them though, and there'd be a fair amount of force against the shock on a Minor unless something was done there too, IMO.

[paulhumphries]

and there'd be a fair amount of force against the shock on a Minor unless something was done there too, IMO.

Most of the (static) loads of a Minor suspension are taken on the lower arm.
Basically think of it like this - where is the torsion bar attached ? The arm, whether upper or lower, where spring medium attaches is where the weight of a vehicle is carried.
On a Minor if you remove the front shock the car doesn't drop to the floor as long as you keep the upright vertical. That is because the lower arm is taking all the weight. Try it the other way round and see what happens if you remove the lower arm
Marina / Ital uprights already have a ball joint on their uppers and my theorectical idea would be to use them thus gaining the disc brakes at same time without having to use the bearing adapters.

Paul Humphries

[Packedup]

I agree the vertical loads are in the lower arm, but it's the rotational forces when hitting the middle pedal that worry me. You're going to be putting a lot more of the turning effort into the upper arm/ shock than you would with the solid lower trunion.

If you had the upper mount ball jointed into an arm that solidly fixed to the shell with a reasonable length bearing or bush, and had a telescopic shock (as the lever arm would no longer be attached) I reckon you'd have a good setup. I'd really not be wanting to add to the forces moving the damper arm laterally as I can't see the bushes in it lasting at all long that way!

Basically I'm think you'd go twin wishbone (with the lower wishbone being the existing design with a balljoint in place of trunion).

And yes, I've had these sorts of thoughts myself

[paulhumphries]

I agree the vertical loads are in the lower arm, but it's the rotational forces when hitting the middle pedal that worry me. You're going to be putting a lot more of the turning effort into the upper arm/ shock than you would with the solid lower trunion.

If you had the upper mount ball jointed into an arm that solidly fixed to the shell with a reasonable length bearing or bush, and had a telescopic shock (as the lever arm would no longer be attached) I reckon you'd have a good setup. I'd really not be wanting to add to the forces moving the damper arm laterally as I can't see the bushes in it lasting at all long that way!

Basically I'm think you'd go twin wishbone (with the lower wishbone being the existing design with a balljoint in place of trunion).

And yes, I've had these sorts of thoughts myself

OK.
Thanks for input.
Next idea then is use MGB type shocks - double armtype like wishbones.
http://cgi.ebay.co.uk/MGB-Front-shock-a ... dZViewItem
It's need quite a bit of adapting of the chassis leg to provide a solid mount for them but I cann't see why they wouldn't work.
Might be easier though to adapt a whole MGB cross crossmember and converting that to ball joint lower
MGB rear axle is also a very good fit under a Minor - and wheels are 14".

Paul Humphries

[Packedup]

Next idea then is use MGB type shocks - double armtype like wishbones.
http://cgi.ebay.co.uk/MGB-Front-shock-a ... dZViewItem
Paul Humphries

Hmmm... I wouldn't say they were perfect (didn't the B also have trunions?), but they're a lot more suitable than the standard minor ones I reckon! And cheap/ plentiful enough to live with any accelerated wear in the bushes

Certainly having double the load bearing surface as well as the far better upper location provided by doubling the arms would have to help, but yeah, getting them attached to the shell wouldn't be entirely straigtforward...

Something like http://www.mgcars.org.uk/frontline/frntsus.htm in Minor form would seem to be a good solution - Stick balljoints top and bottom and use a top arm bracket that bolts to the original damper mounts (though, again, I'm not sure that's overly strong as is, and there'll be different loads gonig through it than it was designed for). To make something like that yourself (or to adapt Fleabay finds) might be easier than trying to mount MGB dampers

Of course, all this messing with improving the front suspension would seem silly unless you also came up with an independent rear to match

[bigginger]

I'll be coy about naming names (because I'm not allowed to, as a mod), but the same type of double wishbone set up is available commercially.

[aupickup]

[bmcecosse]

It would be a whole lot easier to either buy and run an MGB if that's the suspension you want - or convert the Minor front end to McPherson struts !

[leyther8008]

In the seventies didnt people bolt the cross members from HC vivas in? I seem to remeber it was a fully bolt in conversion as well with no welding. gave you disc brakes and double wishbone suspension in one hit.

[plastic_orange]

Wasn't really a bolt in conversion with HC, but the HA more or less was, but ride height was too high if you used minor chassis legs. Mine has a full chevette front clip, but this is welded to a fabricated framework - works well though.
Other popular front end was triumph vitesse etc.

Pete

[kennatt]

mgb had kig pin and bushes at front not trunnions but you can buy a complete cross member converted to telescopic and ball joints but would cost more than the average minor was worth.

[paulhumphries]

mgb had kig pin and bushes at front not trunnions but you can buy a complete cross member converted to telescopic and ball joints but would cost more than the average minor was worth.

A mate recently sent a complete spare MGB front crossmeber and rear axle to the scrap yard.
I had a look and although adaptable the front chassis legs would need "kicking up" to accomodate otherwise the ride hight would be increased by around 6 "
He had just rebuilt the front suspension on his MGB and the parts prices were reasonable but still dearer then Minor items. The kinkpins needed reaming and still greasing. His had previously seized hence the rebuild.
I've decided, despite my original ideals to change to ball joints, to keep everything as standard - including lever arm shocks.
One thing I intend "playing" with, however, is remote grease nipples within the engine bay to avoid having to remove the wheels every couple of months.
I've seen this done of HGV's using "off the shelf" parts.

Paul Humphries

[alex_holden]

Can you not get to the nipples with the wheels still on by using a grease gun with a flexible hose?

[paulhumphries]

Can you not get to the nipples with the wheels still on by using a grease gun with a flexible hose?

Probably but I have a left leg problem (knee dislocates and hip pain - both due to birth defect and a later accident) so it's easier, for me, to remove the wheel than crawl around.
Wished I'd got enough room for a 4 post lift but I don't think my neighbours would be very please if I installed one in the drive of my semi
I don't like small spaces so a pit in the garage or under the carport isn't an option either. In fact I do 99% of all DIY jobs outside rather than undercover.
Accepted the garage the garge is full and as is carport (plus the two lock-up's !) but I prefer working outdoors


Paul Humphries

[dunketh]

I like wokring outdoors too although I dont really have a choice.

Spending your weekends with a sunburnt neck, greasy hands and a dirty cup of tea is what its all about.

[bmcecosse]

I too have considered the 4 post lift - could keep one car on the lift and one under which would solve some of my parking problems!