suspension improvments - French Document

[Duncan]

View attachment CLIO V6. Liaison au sol.pdf

I found this document from V6 Passion. Its in french, google translate makes a dog dinner of it, but is quite interesting to read. It highlights some of the weak points of the suspension and discusses a number of possible improvements as well as their downfalls.

The ones that I thought were particularly interesting where replacing the front tie rod ends from the standard (A Laguna Part) to a Vel Satis part, which increases the front track by 25mm on the ph1 as well as appearing to offer other benefits to the set up.

Also it discusses the ph2 rear anti roll bar which was designed, but not put on the production car (made it a bit tricker in the wet, but better in the dry). Renault Sport after sales appeared to of actually offered the anti roll bar when new.

 

[HaventgotaClio]

That looks like an excellent read. There's a translate function on most camera phones which might do better at translating it.
The ph2 rear anti roll bar sounds like a stiffened up version if it improved dry handling but compromised wet handling. Wouldn't be a hugely difficult bit of kit to manufacture but without the details on it there would be a fair bit of trial and error involved until you found the sweet spot. Anti roll bar setup makes a huge difference to handling.

 

[Duncan]

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Heres some photos of one fitted. This is what a chap in France has recreated.


Some additional discussion from V6 passion (original thread).

The last comment is from an engineer who worked on the phase 2. Which I have roughly translated below:

"The chassis has not much to do with it. By cons, the flexibility of springs and dampers, yes these are first thing to check.

Never stiffen the back if you do not stiffen the front under penalty of increasing over steer behaviour. Personally, I drove the with the prototype anti roll bar of 14 but only in the dry. In the wet, I unplugged because it became too sensitive ... unless you want to drift ..

I strongly advise against ARB on a phase 1 that does not have the improved rear end of the phase 2 and much more (too) flexible springs. it would make it much too sensitive

= So move to springs / phase 2 damping or aftermarket (Viarouge or other brand) to find a proper balance.
= If you are there on a phase 1, also put the rear subframe of phase2 ...
= Anyway, a phase 1 subframe does not have the support of reception of this famous ghost bar which has not never existed ... All phase 2 subframes have the mounting points.

Even on a phase 2, if someone complains of body roll, I can not recommend enough to invest also in a combined kit spring / damp worthy of this name... it will change your life. "

so the ARB sounds a bit bitter sweet. Perfect if you want to do sunny track days, not so much for general use.

 

[rustedandrotten]

ARB sounds the fastest way to visit the scenery! 14 sounds like diameter which is pretty thin but depends on leverage so should not be doing a lot but indicates otherwise [smilie=icon_eek.gif] From that it seems that the P2 rear end set up is pretty much there but could benefit from spring and damper change.

 

[Brett]

I have a ph2 rear anti roll bar on mine. It is a very thin item over its length to be honest. Of coarse, it’s very easy to make adjustable with a few holes drilled in the blades but that will only allow you to make it stiffer. I have also added an adjustable front sway bar too compliment the rear.
Many seem to forget the geometry. I have made a roll centre correct kit for both front and rear suspension as it’ll sit 35-40mm lower at the rear and about 25-30mm up front. The car now uses two springs in the rear corners and 3 at the front corners. All being different spring rates. This is to maintain a smooth ride and road contact while reducing large amounts of weight transfer under braking and throttle lift.
Our cars, ph1 in particular, have so many ways to be improved. Having been out in a fair few different types of v6’s on track as well as the road so many are different. Neither phase is any different either considering both share pretty much identicle subframe pick up points as datums to start with.
Great to see some of the french boys sharing info. They certainly drive their cars way more than we do over here and a damn site harder :approve: