Improving the Anti-Roll Bar

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Monty-4
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Improving the Anti-Roll Bar

Post by Monty-4 »

When poking around at the front of my car to find an irritating suspension knock I noticed a lovely hole in the chassis leg (since welded) and badly worn "bushes", or rather plastic hydraulic clamps, that hold the current off-the-shelf front anti-roll bar kit to the car. This got me wondering, would there be a quick and easy way to improve upon this?

A quick search later and I find that the 19mm ID hydraulic clamps are not only dead cheap but can be had in aluminium, which I think may be tougher but still not harder than the bar itself, and a "sound deadening" variety that has a rubber bush insert of sorts. Both potential easy swaps, but still not really designed for the task at hand. A second search led me to SuperFlex's univeral anti-roll bar bushes and mounts (Super Pro also do an identical looking set), which look encouragingly like they could be adapted to work with the existing chassis leg plate with no effort at all other than sourcing a shorter screw.

Furthermore, could the mount to the suspension arms and tie bar be improved with an off the shelf rose jointed rod end bearing?

Has anybody else successfully modified the existing anti-roll bar? I'm not looking to be taunted by those fortunate enough to have the earlier kit!
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Re: Improving the Anti-Roll Bar

Post by Sleeper »

When I fitted mine I found the plastic "hollow" mountings woefully inadequate so filled them with epoxy putty..

just an idea....

John :wink:
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Monty-4
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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

I suppose that would harden them up, although I was looking to ditch the plastic thingies entirely!
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philthehill
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Re: Improving the Anti-Roll Bar

Post by philthehill »

Marina anti roll bar link.jpg
Marina anti roll bar link.jpg (304.27 KiB) Viewed 2816 times
Marina thick lower suspension arm.jpg
Marina thick lower suspension arm.jpg (233.39 KiB) Viewed 2818 times
The current anti-roll bar mounts and links can be greatly improved.
Use this type of mount on the end of the roll bar in conjunction with a rose joint(s) connected to either the thick/thin suspension arm as per the Morris Marina/Ital or the tie bar rear bolt.
Photos attached of the Marina thick arm which is the same as the Minor plus the roll bar mount hole and the link between suspension arms and roll bar.

https://www.merlinmotorsport.co.uk/p/an ... r-arb-sc-8

Rubber roll bar mounts held in 'P' clamps are best.

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Monty-4
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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

Thanks phil.

I'm going to give fitting the following mount type a try, perhaps somebody knows the size of the allen-headed screw that holds the existing pipe clamps to the bracket?
s-l1600.jpg
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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

The brackets with the SuperPro bushes are reassuringly heavy duty, those are M10 bolts that I'll likely swap for 3/8".
20180829_173709.jpg
20180829_173709.jpg (105.02 KiB) Viewed 2660 times
Now I'm wondering about doing this properly with an internal strengthening tube like the eyebolts...
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Re: Improving the Anti-Roll Bar

Post by philthehill »

The front of the chassis rail has no inherent compression strength so the strengthening tube will only be effective if the tube is welded to the chassis rail at either end and which is as you say similar to the eye bolt tube.
If a tube is not fitted and welded to the chassis rail you will be constantly tightening the through bolts.

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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

My thoughts exactly, the "original" off the shelf kit will crush the chassis leg if overtightened given the lack of strengthening tube. Not a massive job and steel tube is cheap at least.
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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

Poly bushed front mounts on. 3/8" bolts with 12mm steel tube strengeners welded in (9.6mm ID fit perfectly around the bolts) and some steel taper washers to make up the angle of the chassis leg on the inside of the engine bay. Conveniently the bolts come through just in front and behind the engine mounts.

What a difference! The setup allows a little more roll but it is predictably limited and the front no longer becomes light and skittish over rough surfaces. I imagine this is due to the mounts allowing some lateral movement and the small amount of flex in the bushes.

I'll look at rose-joints and slide-clamps when the end-bushes get tired. :)
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Re: Improving the Anti-Roll Bar

Post by IslipMinor »

I have what looks like the same antiroll bar, which was fitted in 1998 as part of the complete restoration project. I did not like the idea of clamping the mounting bracket over the new chassis leg, so got some 5/16" (8mm) plate and made solid mounting plates that I drilled/tapped and then welded them to the front inclined face of the chassis legs.

When originally fitted the bush that slides over the end of the roll bar was only available in rubber, but was replaced with polyurethane a few years ago, and at the same time I replaced the plastic blocks, as a precaution.

The original fitment was 60,000+ miles ago, and they have done the job very well indeed (I do initially fill the grooves with copperslip grease), but otherwise no maintenance at all.
IMG_3016.JPG
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IMG_3017.JPG
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Monty-4
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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

I like the idea of the tapped plate, adding strength and certainly less fiddly than tightening a nut inside the engine bay whilst holding the screw still under the car!

My concern with the plastic blocks is that they wear and the ARB can cause an audible knock - hence my preference for a polyurethane bush up front instead.
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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

Thread resurrection!

I'm reassembling my car again (don't ask about how bored/silly I got in lockdowns) and have found myself a Marina/Ital rear ARB.

I wonder if clever folk might have suggestions on the best method of mounting the rear ARB. I understand I'll be welding brackets onto the axle, but what about the ends? Will I be reinforcing the floor or adding tube to the rear rails where the dampers mount?
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Re: Improving the Anti-Roll Bar

Post by philthehill »

I have been recently been looking into the possibility of fitting a Marina rear anti-roll bar to the rear axle of my Morris Minor and come up with the following ideas which may be of use.
First weld a couple of axle mounts as per link below to the top of the Minor axle casing using the original Marina anti-roll bar mounts as a placement guide.
https://www.morrisminorspares.com/rear- ... mm-p831292
Obtain and fit a couple of anti-roll bar mounts to the above axle mounts see link below. There are several types to choose from (note the style of mounts are correct but the size may not be - requires confirmation of the anti-roll bar diameter).
https://www.merlinmotorsport.co.uk/p/an ... ?pn=ARB-12
https://www.ebay.co.uk/itm/262690550403 ... R8iVhpG2YQ
The front of the Marina rear anti-roll bar when fitted to a Morris Marina is mounted inside a 'U' section channel welded to the underside of the car. That can easily be replicated on the underside of a Morris Minor beneath the rear seat.
Fit the anti-roll bar to the axle first and then hold up the bar to determine the front mounting point for the anti-roll bar.
The size of the 'U' channel will be dictated by the type of link used between the front end of the anti-roll bar and the bracket attached to the underside of the car. You can either use the original Marina anti-roll bar end joint which is just a captive metalastic type bush fitted on the front end of the anti roll bar and placed and bolted inside the 'U' Channel or do the job properly and fit a rose jointed link. I prefer the latter.

As regards the front anti-roll bar here is a revised front suspension set up for my Minor.
Note the rose joint link to the existing anti roll bar. The link has now been again revised using a Owen Burton anti-roll bar with sliding rose joint linking the anti-roll bar to the suspension arm.
Marina suspension 22.JPG
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Monty-4
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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

That's great phil, I've also sourced some Marina torsion bars (normal car thickness) and will be following your example for fabricating brackets for those.

I admit I can't quite visualise how the sliding rose joints work with the ARB, do you have any photos of it assembled?
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Re: Improving the Anti-Roll Bar

Post by philthehill »

Here is a photo of the revised anti-roll bar link which fits between the reduced end diameter of the Owen Burton type anti -roll bar and the lower suspension arm.
The link in the photo above was made to suit the original 1960's anti-roll bar which had a eye on its end and the articulation was allowed by the rubber bushes.
The red anodised sliding joint is secured in place by a grub screw.
Having the sliding joint and two rose joints ensures that the link can be fitted in its optimum position.
anti roll bar link 1.JPG
anti roll bar link 1.JPG (808.72 KiB) Viewed 851 times
The fitment of the Owen Burton type anti-roll bar at its rear end is a bit of a compromise and not that efficient but it does work after a fashion.
My original 1960's had a better articulation at its rear end than the Owen Burton type anti-roll bar but not as good as the link in the photo directly above.

As regards fitting the Marina torsion bars - if you do not have a pair of the Owen Burton Marina to Minor torsion bar fitting adapters you can always cut a section off the rear of a Minor torsion bar and use that instead.

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Re: Improving the Anti-Roll Bar

Post by Monty-4 »

That's great, thanks phil!
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