ARB Mounts

ARB Mounts

Author
Discussion

johno

Original Poster:

8,427 posts

283 months

Friday 22nd February 2002
quotequote all
Changing the ARB mounts for Poly ones which arrived today.

I have had the ARB undone before at the suspension arm end but haven't delved into the chassis mount area previously. Any suggestions on potential issues ??

I can guess at a few but often you guys come up with something else !!!

Cheers

Mark

GreenV8S

30,210 posts

285 months

Friday 22nd February 2002
quotequote all
quote:
Changing the ARB mounts for Poly ones which arrived today.

I have had the ARB undone before at the suspension arm end but haven't delved into the chassis mount area previously. Any suggestions on potential issues ??

I can guess at a few but often you guys come up with something else !!!

Cheers

Mark



If your ARB mounts are like mine, the chassis mounts are virtually rigid with two thin layers of hard rubber sandwiching a metal sleeve. Looks like a good design to allow the bar to twist but not move up and down. Even going metal-to-metal here I couldn't spot the difference. Most of the flex comes from the naff drop links at the outer ends which have soft rubber all over the place. Replace these with decent rod end bearings and it makes a noticeable difference. If you do this, you will need to space the lower mounts away from the wishbones to prevent them fouling. Merlin Motorsport do the clamp-on mounts that you need to attach the upper end to the ARB.

Cheers,
Peter Humphries (and a green V8S)

johno

Original Poster:

8,427 posts

283 months

Friday 22nd February 2002
quotequote all
quote:

Most of the flex comes from the naff drop links at the outer ends which have soft rubber all over the place. Replace these with decent rod end bearings and it makes a noticeable difference. If you do this, you will need to space the lower mounts away from the wishbones to prevent them fouling. Merlin Motorsport do the clamp-on mounts that you need to attach the upper end to the ARB.

Cheers,
Peter Humphries (and a green V8S)



Peter,

Got any pictures of this arrangement. I am pretty sure I understand what you mean as I was looking around an original Tuscan at the Brighton speed trial with this kind of set up and Alloy ARB mounts.

Cheers

Mark

roulli

175 posts

270 months

Saturday 23rd February 2002
quotequote all
Gentlemen,

I'm sorry, what what does ARB stand for?

Cheers Patrick

Paceracing

729 posts

267 months

Saturday 23rd February 2002
quotequote all
Rouilly,

ARB, Anti-Roll Bar.

Peter,

Presumably you now have the ability to make the roll rate adjustable then? I understand what you mean about wishbone fouling, have you had new lower wishbone mounts made or did you adapt the old ones? Oh and Merlin's phone number and where are they?

Cheers, Jas.

GreenV8S

30,210 posts

285 months

Saturday 23rd February 2002
quotequote all
quote:

Rouilly,

ARB, Anti-Roll Bar.

Peter,

Presumably you now have the ability to make the roll rate adjustable then? I understand what you mean about wishbone fouling, have you had new lower wishbone mounts made or did you adapt the old ones? Oh and Merlin's phone number and where are they?

Cheers, Jas.



Merlin Motorsport www.merlinmotorsport.co.uk 01249 782101.

I theory they're adjustable, in practice I haven't got enough adjustment available to make any difference to the handling. All the problems we talked about at Goodwood, basically the drop link is already as far back as it can go.

Haven't changed the mounting brackets on the wishbone, as you know the drop links are mounted under the bottom wishbone slightly in front of it, and when you fit rod end bearings you need to space it forwards a little to stop it fouling. Alternative is to space it a *long* way backwards and fit the drop link behind the wishbone, but I don't like the amount of bending that puts into the bracket.

Getting back to the chassis mounts, the only issue I can see is it was hard to get the drop links off the end of the bar (I had to use a puller), and probably next to impossible to get them back on again afterwards (I replaced them with the Merlin fittings so no problem). So as long as the replacement bushes are split, it should be OK. The original ones aren't, so they'll be trapped by the drop links, but you don't actually *need* to take them right off so that's OK.

Cheers,
Peter Humphries (and a green V8S)

sharpy

39 posts

284 months

Friday 22nd November 2002
quotequote all
quote:
--------------------------------------------------------------------------------

Most of the flex comes from the naff drop links at the outer ends which have soft rubber all over the place. Replace these with decent rod end bearings and it makes a noticeable difference. If you do this, you will need to space the lower mounts away from the wishbones to prevent them fouling. Merlin Motorsport do the clamp-on mounts that you need to attach the upper end to the ARB.

Cheers,
Peter Humphries (and a green V8S)

--------------------------------------------------------------------------------

I am looking in to having a go at this modification on my S3. I have looked at the Merlin catalogue and viewed pictures of the rod end bearings which appear to have a threaded fitment. I presume I have to get the drop link, pin and washer off the ARB end first but how do I then attach the rod end bearing to the ARB? On reading Pete's post again the answer is clearly, "use the Merlin clamp on mounts". Again looking in the catalogue I see polypropylene ARB clamps, are these what are meant? surely they wouldn't be strong enough? and how would the threaded rod end bearing attach to it? Any advice would be much appreciated,

TIA

Dave S3c

greenv8s

30,210 posts

285 months

Saturday 23rd November 2002
quotequote all

sharpy said: quote:
--------------------------------------------------------------------------------

Most of the flex comes from the naff drop links at the outer ends which have soft rubber all over the place. Replace these with decent rod end bearings and it makes a noticeable difference. If you do this, you will need to space the lower mounts away from the wishbones to prevent them fouling. Merlin Motorsport do the clamp-on mounts that you need to attach the upper end to the ARB.

Cheers,
Peter Humphries (and a green V8S)

--------------------------------------------------------------------------------

I am looking in to having a go at this modification on my S3. I have looked at the Merlin catalogue and viewed pictures of the rod end bearings which appear to have a threaded fitment. I presume I have to get the drop link, pin and washer off the ARB end first but how do I then attach the rod end bearing to the ARB? On reading Pete's post again the answer is clearly, "use the Merlin clamp on mounts". Again looking in the catalogue I see polypropylene ARB clamps, are these what are meant? surely they wouldn't be strong enough? and how would the threaded rod end bearing attach to it? Any advice would be much appreciated,

TIA

Dave S3c


You want the annodised aluminium slide clamps (size to fit your ARB, I'm guessing you have the 1" bar?), and a pair of male and female rod end bearings screwed into each other to make a drop link.

sharpy

39 posts

284 months

Saturday 23rd November 2002
quotequote all

greenv8s said:

You want the annodised aluminium slide clamps (size to fit your ARB, I'm guessing you have the 1" bar?), and a pair of male and female rod end bearings screwed into each other to make a drop link.


Thanks Pete,
so I assume that I bolt the upper bearing to the ARB slide clamp then bolt the lower bearing to the lower wishbone mount, spacing the lower bearing forwards say 0.5cm?
When I take the original drop link off, is it secured with a split pin washer arrangement, as pictured in the S Bible (p158), and will I need a special tool to remove the pin and/or drop link?

Regards

Dave S3c

greenv8s

30,210 posts

285 months

Saturday 23rd November 2002
quotequote all

sharpy said:
Thanks Pete,
so I assume that I bolt the upper bearing to the ARB slide clamp then bolt the lower bearing to the lower wishbone mount, spacing the lower bearing forwards say 0.5cm?
When I take the original drop link off, is it secured with a split pin washer arrangement, as pictured in the S Bible (p158), and will I need a special tool to remove the pin and/or drop link?

Regards

Dave S3c




Mine was a split pin & washer, but the bush was a tight fit on the end of the ARB and needed a puller to get it off. Make sure you have the parts you need for the solid drop links before you do this, I very much doubt the rubber bush will go back on again afterwards!

BTW I spaced mine forward about 10mm to clear the wishbone, short piece of mild steel sleeving does the job nicely.

Cheers,
Peter Humphries (and a green V8S)

sharpy

39 posts

284 months

Saturday 23rd November 2002
quotequote all
Peter,

I'm intrigued to know how this set up can allow roll rate adjustability?

Please forgive my mechanical ignorance but what is a puller and how does it work?

Regards,

Dave S3c

greenv8s

30,210 posts

285 months

Saturday 23rd November 2002
quotequote all

sharpy said: Peter,

I'm intrigued to know how this set up can allow roll rate adjustability?

Please forgive my mechanical ignorance but what is a puller and how does it work?

Regards,

Dave S3c


In theory, you can reduce the roll stiffness by sliding the slide clamps out towards the end of the ARB. In practice you will find that the geometry of the drop links prevents you from moving them far enough to make any difference. The puller was just a device for pulling the original droplink off the end of the ARB, the bush was *really* tight and needed a lot of force to shift it.

Cheers,
Peter Humphries (and a green V8S)

sharpy

39 posts

284 months

Saturday 23rd November 2002
quotequote all

Thanks Peter, that's a great help.

Regards,

Dave S3c