What Suspension ?

[Guest Antoni1.9]

Looking for some advice on suspension for my 1.9 Gi track car.

 

I have sorted out the safety side of the car, the engine is healthly and the brakes have been uprated.

 

At the moment, the car has totally standard peugeot suspension and 63,000 miles from new.

 

The only purpose of the car is track days - although a little comfort on the journeys would'nt go amiss so some suspension mods would certainly help.

 

I have one strut in pieces following Castle Coombe on Saturday as the NSF wheel bearing was protesting - so:

 

What is the general advice please regarding the most cost effective improvements to suspension for track use - Front and rear - Springs / rates and dampers.

 

I look forward to your recommendations and a multi stage coversion would be considered as cash is not so free at the moment after preparing the car to this stage.

 

Thanks in advance.

 

Antoni

[Alan_M 66 1 Cars]

I would'nt be able to tell you the best one, but i can recommend the Bilstein Sprintline kit.

 

Don't think its for the track though. WOuld've thought Bilstein Adjustables would be better.

 

Adi is the man to speak to, especially after his comments/advice on the PGAC forum.

 

I need some shorter springs!

[Adi 0]

The real problem with any set up is money. It would be easy to suggest good quality products and ones that will prove effective. But if the budget is limted then it will prove some what more difficult.

 

Bilstein Sprintline dampers are good for the track. Not good for loose surfaces, but ok for the track. Any thing that is adjustable is going to be better for you to set the car up to how you like it. But any coilover kit or adjustable damping will be more expensive.

There is the Koni adjustable dampers....but they will be a full stroke damper so will not keep a short spring in place all the time. I suppose this wouldn't be a problem on the track.....but on the road where the suspension could go into full droop and enable the spring to get out of position....then this could prove a problem.

 

As I said in the Mi16 front spring thread......205 race cars use spring rates around the 200lb mark. Normal uprated front springs for the road......will be around the 150lb mark. They will probably have 5 1/3 coils on a 6" dia spring as opposed to the higher rate 4 1/3 coils for the 180lb mark.

 

Leda will do a good coilover set up that works well on the track. But you will be looking at around £800 for the 2 front coilovers and 2 rear dampers. Then that isn't there best damper.

 

Let me know what your budget is......or what you want it to be......and take it from there.

[Guest Jon1T]

Adi - mines running 300lb Leda springs up front and other stock hatcvhe racers are using 200lb springs as a minimum!

 

But as as you say Leda are always a good place to go and their products widely rated on 205s - jsut ring them up and tell em what you want and they'll help you out - but you'll be looking at about £500...

 

Jon

[Guest smckeown]

i'm in the market for a dedicated track day setup too. I phones leda up the other day for a chat, and they could only tell me what they had for sale, rather what would be suitable for me

 

I'd definately after some leda's, just not sure which option to take, oil / oil/gas or gas

 

sean

[Adi 0]

Adi - mines running 300lb Leda springs up front

 

I can only tell you the info I have as to what is a decent set up. Yes certain people have used 300lb springs......but there can be a point where the car is over sprung. You have also to think of the rear.......its a case of getting a good balance.

 

just not sure which option to take, oil / oil/gas or gas

 

All dampers use oil. It is just whether they use any gas....low gas pressure or high gas pressure.

In Ledas case.....the monotube high gas pressure are the ones with the reserve canistor. They are very expensive.

The low gas pressure twin tube damper would be the best comprimise.

[Hilgie 16 2 Cars]

I have Koni dampers all around on Merwede springs.

 

Using the 309GTi16V setup allaround (rear beam has thicker torsionbars and wider track and front suspension has wider track and thicker anti-rollbar).

[Guest Jon1T]

Well 200lb minimum for race/track use up to 300lb depending on the usual factors - and of course you can always adjust bump/rebound on SH spec dampers

[Adi 0]

you can always adjust bump/rebound on SH spec dampers

 

From the regulations I've read.....stock hatch cant' have adjustable damping. Adjustable ride height....yes.....but not in damping.

 

The spring poundage is all personal choice as to how you set a car up. I've seen various hatchbacks on the track with 1000lb springs and upwards. But they have had them at the rear as well. The 205 is limited at the rear. A well balance car is a faster car.

[Alan_M 66 1 Cars]

Adi>>From your post on the PGAC forum, would it be better for me to bin the springs that came with the Sprintlne kit then and getting shorter ones??

 

Am looking at Eibach at the moment (30-35mm).

[crf450 0 1 Cars]

Adi,I am planning a bit of a spend this winter on some decent suspension for my car.I have no idea on spring weights and I'm looking for some good advice in this area.

I read somewhere before that 200lbs is about right for the front, but as I am converting the rear to coilovers aswell I could do with knowing what to go for as a starting piont.I am mounting the rear coilovers of an extended stub axle(on the center line of the wheel) so I wont have a ratio to take into consideration.Could I work the spring rates out from the rear corner weights?

Where did you get your experience in setting up 205's?

cheers Martin

[Guest Antoni1.9]

Thanks for all of the replies.

 

I've just come home after a couple of days out. So I'll go through the posts, digest the info & come back with some more queries if that's ok ?.

 

I have potentially available through the forum a Bilstein streetline kit - I am waiting for some info, but if anyone has any experience, comments would be gratefully received.

 

I didnt really have any budget in mind as I thought about suspension because the strut is off. If it is not possible to do anything half decent for a couple of hundred quid - possibly by using 2nd hand equipment, then it may be wise to rebuild the stut and wait until i can buy the right stuff.

 

Can lower/stiffer springs be fitted with the OE dampers ?, or will this be unbalanced ?

 

I also have available 306 S16 rear dampers (actually have a complete low mileage rear beam) - will these fit the 205 by any chance?

 

Thanks in advance

 

Antoni

[fiji bob 0]

im using streetline dampers with eibach springs the fronts fine but i still need to lower the back to match so it doesnt feel too good at the moment

[Guest Jon1T]

Adi - don't want to go off topic and argue, but the Stock Hatch does not allow SEPERATE bump and rebound adjustment - ie they adjust to 'hard' or 'soft' which is a combination or compression and rebound, is it not?

[Adi 0]

but the Stock Hatch does not allow SEPERATE bump and rebound adjustment - ie they adjust to 'hard' or 'soft' which is a combination or compression and rebound, is it not?

 

Read different regs now.....and they are like you say. Don't know what I was reading before then....ah well.

One way adjustable dampers work with rebound only.

 

From your post on the PGAC forum, would it be better for me to bin the springs that came with the Sprintlne kit then and getting shorter ones??

 

Can't honestly remember totally the details of what I said. I remember the chap saying he was doing part rough surface and part track. In which case I would question the Sprintline stuff.

 

The only problem with using Eibachs with Sprintline dampers......is that the Sprints are short stroke dampers.....for spring -40mm and shorter. If you use -30mm springs....the damper will trap the spring....and not allow it to use the full length.

Also I doubt the Eibach rate will not be high enough. I have heard of probs with Eibachs rate on rough stuff. But that depends on exactly what you're using them for.

 

CRF540,

 

rear coilovers........sounds good......but in reality.....as long as the balance of torsion bar, roll bar and dampers are right.....the original set up can be as good if not better. I've seen some of these conversion before.....and they've not really been any quicker.

 

My experience is handling in general. It may sound wrong........but all suspension and vehicle dynamics have the same theory. So as long as you understand the suspension layout......its just balancing out the weight transfer. That is where the handling balance comes from.

[cybernck 402 1 Cars]

but as I am converting the rear to coilovers aswell I could do with knowing what to go for as a starting piont.I am mounting the rear coilovers of an extended stub axle(on the center line of the wheel) so I wont have a ratio to take into consideration.

martin> check these pics out:

 

 

 

complete story in pics here.

 

 

according to my observations they are mounted on normal mounting points on

the trailing arm though (hilgert confirmed that) but i don't know what effects

does it cause because of the suspension travel ratio .

 

btw, i'm thinking of converting to coilovers as well .

 

 

adi> yeah, torsion bars setup tuned for specific purpose is very good, but with

coilovers you can easily adjust the height, rebound and firmness so a lot more

flexible setup. especially when used with coilover up front as well.

[Adi 0]

they are mounted on normal mounting points on

the trailing arm though (hilgert confirmed that) but i don't know what effects

does it cause because of the suspension travel ratio

 

Well in the respect of improving how the suspension works.....there will be no improvement what so ever.

The bad point on the torsion beam axle on he Pug is the ratio of damper movement to wheel movement. This is between 3-1 and 5-1. That is 3-5 inch of wheel movement to 1 inch of damper movement. When you look at an F1 car, they have exactly the opposite. The damper will move between 3-5 times the wheel movement. That is so the damper can work to the maximum. This is what improves handling and grip.

 

The other thing you have to remember about the rear beam is.....that both the rear roll bar and the torsion bars provide stability for the rear arms. They ensure that the rear arm bearings have as little strain....side to side....as poss. Now if the torsion bars are removed......where is the bracing to reduce the sideways load on the arms??? The rear arm bearings will be breaking every 2 mins.

 

torsion bars setup tuned for specific purpose is very good, but with

coilovers you can easily adjust the height, rebound and firmness so a lot more

flexible setup. especially when used with coilover up front as well

 

The only advantage that coilovers have at the rear......is changing the height of a road car when going on a track day. When set up for specific purposes like rallying, the torsion bar set up will prove quicker when set up correctly.....in the stage times and testing.....than other set ups. As far as damping goes, you can get 3 way adjustable dampers for the beam axle.....so high speed damping, low speed damping...and compresion damping. You can also change the height of the torsion bars by mm increments....it just takes longer.

[crf450 0 1 Cars]

Adi,this is a PM I sent Batfink the other day that explains some of my reasons for wanting to coilover the rear.

Allright Kev,

 

My thinking is the rear beam weighs a ton and I reckon reduce this by 50% buy loosing the torsion bars shockers and all assciated mountings,Also the geometry of the rear shockers isn't ideal.The problem is the radius of the trailing arm shock mouting piont is too small which means as it moves through it travel the geometry changes.

My set up will involve loosing all the surplus stuff off the beam which I've allready metioned and making a new stub axels for each trailing arm which will be extended on the inside off the arm to mount the coilovers on.After I've done this it will be just a case of fitting turrets to the wheel arches in the same way they do when fitting coil overs to the rear of a mini.

 

Nic, thanks for the photos, it looks like that car has retained the shockers in there origonal place which is one of my main reasons for changing.

cheers martin

[perfecto pug 0]

the main weight of the rear axel is the arms, if they could be made from aluminium??? or something you could drastically reduce the weight of the whole rear axel assembly

[crf450 0 1 Cars]

I agree the arms are heavy, but thats my thinking.If you cut the torsion bar mounts off the arms you would loose a lot of weight.

Cheers Martin

[Adi 0]

Martin,

 

I understand the points you're making. But you haven't understood my points...maybe I haven't explained well enough.

 

Any rear trailing arm has to be braced to protect them from lateral movement.

With the rear beam axle on the Pugs......part of this comes from the torsion bars. The torsion bars not only act as a spring.....but a sideways brace. The anti roll bar through the tube also helps in this manner.

If you remove the torsion bars.....how are you going to brace the rear arms and protect the rear arm bearings from lateral movement????

[C_W 3 1 Cars]

Martin,

 

I understand the points you're making. But you haven't understood my points...maybe I haven't explained well enough.

 

Any rear trailing arm has to be braced to protect them from lateral movement.

With the rear beam axle on the Pugs......part of this comes from the torsion bars. The torsion bars not only act as a spring.....but a sideways brace. The anti roll bar through the tube also helps in this manner.

If you remove the torsion bars.....how are you going to brace the rear arms and protect the rear arm bearings from lateral movement????

He could machine off the splines and put roller bearings in both ends??? Thus removing the suspension of the torsion bars but leaving the bracing aspect? But not the weight of it though. But having said that I don't think the torsion bars weigh that much.

 

Like someone has said the trailing arms weigh the most. In fact a complete rear beam isn't that heavy I don't think, I can carry one on my own, and I bet it does stiffen the rear end of the car too to a degree.

[Adi 0]

He could machine off the splines and put roller bearings in both ends???

 

right idea...but you would only need to do that on the trailing arm. No need on the other side.

 

By the time the strengthening and turreting is added...you may as well fit a space frame to the rear and have double wishbones. It would be a dam site easier.

[crf450 0 1 Cars]

Adi,I understand the piont you are making about thrust forces on the trailing arms but I don't believe this will be a problem that will take much overcoming for me.In fact in the whole sceme of things, I'd classed it as a small consideration.

The way I see it is like this,

The job won't take much doing for me,

To start making a whole new rear suspension set up will be a masive task compared to what I'm doing and will involve making jigs for wishbones and the new beam and drawing up the whole set up to make sure the geometery's goona work,

I do belive I will make a significant weight saving,

Changing spring rates and ride hights will be much easier.

All you are changing is the springing and damping set up which will leave the geometery as Peugeot intended and keep the handling caricteristicks of the 205.

At the end of the day it may not be worth the work but I believe it will be.I will keep you informed of my progress.

Cheers Martin

[Guest Antoni1.9]

What's all this about chaps ??