309 Front & Rear Suspension!

[Alan_M 66 1 Cars]

Have been looking into fitting 309 wishbones & shafts to my 205 for a while now to give that little bit of neg. camber.

 

I'm not sure how many have done this conversion and the addition of a 309 rear beam but what are the advantages of both these on a road car (with a few track days chucked in for good measure!)?

[Hilgie 16 2 Cars]

The front is hardly visibible, but it gives some more traction in corners on the track. On the straight however it feels more nervous but that can be solved by giving it some more caster (adjustable topmount).

 

I have noticed that the 309rearbeam makes the 205 more prone to oversteer, probably due to the increased width combined with a short wheelbase.

But it looks fantastic!

[Adi 0]

I have noticed that the 309rearbeam makes the 205 more prone to oversteer

 

Is that whilst using solid rear axle mounts......or still using the std ones???

[Hilgie 16 2 Cars]

Using standard ones....I guess it'll be worse when using solid ones.

[Adi 0]

I guess it'll be worse when using solid ones

 

Exactly the opposite. The solid mounts will stop the axle twist so therefore reduce the main part of the rear end movement. Anything left will be caused by the wider rear track.

The wider rear track shouldn't cause oversteer......just reduce the understeer on initial turn in. This should result in a far sharper turn in. Also more stability when shutting the throttle......through the solid rear mounts.

[Hilgie 16 2 Cars]

I could try it offcourse!! I'll order a set of Group A mounts from Rallycar.com then

 

I'm using Koni yellow dampers all around and Merwede springs (similair to Eibach) upfront.

[Adi 0]

I could try it offcourse!! I'll order a set of Group A mounts from Rallycar.com then

 

Deffo and let me know your thoughts afterwards.

 

The problem with the "passive rear steer" that Peugeot use......is that when you turn into a corner......the initial response is for the front to run wide. You then lift the throttle and the rear end straightens up.......hence "lift off oversteer".

For todays cars......this is not good. The modern cars with superior rear suspensions tend to turn in far sharper.......and less need for the lift off rear end movement.

The rear end of the standard 205GTI is about 2-2 1/2 inches narrower than the front. By fitting the 309 axle the rear end is far wider......BUT is still narrower than the front......by 1/2" - 1". So you may want to measure the front/rear track and fit some spacers to make the rear track as wide as the front. Again this will create sharper and more stable turn in.

 

The 206/307 rear track width is far closer to that of the front track......in fact the 307 rear track is slightly wider than the front track.......as manafacturers now know the benefits of handling and stability this offers.

[cybernck 403 1 Cars]

i agree with hilgie that 309 gti rear beam feels like introducing more oversteer.

 

i also agree with adi and his theory.

 

 

anyway it did give a sharper turn-in but it felt a bit strange until we fitted

309 gti wishbones and 309 gti front arb - now it feels great, far more

balanced. also, negative camber further "sharpened" the steering .

[Adi 0]

i agree with hilgie that 309 gti rear beam feels like introducing more oversteer

 

Which rear axle bushes did you have fitted????

[Ahl 4]

Do the solid rear mounts increase vibration from the rear considerably? Enough to make it unusable as a road car?

[cybernck 403 1 Cars]

adi> left standard ones in there for the time being.

[Adi 0]

Do the solid rear mounts increase vibration from the rear considerably?

 

It all depends on your personal comfort/vibration limits. Some can take a lot of road noise/vibration without a prob......others want as little as possible. That is why the softer rubber is fitted in the first place.

 

I really doubt that the noise vibration will be severely inreased. Just noticably.

[Adi 0]

adi> left standard ones in there for the time being

 

I would expect the oversteer to be increased with the std bushes.....as there is more load on the rear outside wheel with the increased track.

 

I would also expect the oversteer to be reduced with the solid bushes.

 

How much would you say the front end turn in has improved thru the fitting of the wider rear axle??? That is the initial response when the steering wheel is first turned.....and not with a trailing throttle.

[C_W 3 1 Cars]

The faster turn-in "oversteer" is probably something you would get used to I think? When I put a 23/24mm anti-roll bar on mine it felt edgey at first and did appear to "oversteer" but perhaps only because I wasn't used to the better turn-in. Totally used to it now though!