Nasty Handling

[d-9 0]

Ive done the running in phase on my 309 and took it round combe at the weekend, but the handling was horrible, massive understeer most of the time, and then snap oversteer, not at all what a 309 should have.

 

The current spec is:

leda coilovers with fairly stiff springs (300lb maybe)

rear lowered about 30mm

pi stiff as hell rear dampers (grp n coming when ive sourced some bushes for them)

goodyear eagle F1s

 

At the moment the camber is set a little bit negative and the damping is about 1/4 from soft, any suggestions on what i should do to make it handle like a 309 again (current temptation is to put standard suspension back on, as it was fine with that!)

[boombang 2]

I found huge understeer at Combe in my 309 - that was Koni adjustables and springs on front and very hard unknown dampers on fresh beam rear.

 

After that day I turned the damping right down and it was far far better but never great.

 

In your case it may simply be over-sprung or over-damped on the front - bear in mind that over-hard dampers don't acutally increase spring rate, just stop it working properly.

 

May be worth checking beam clearance on bumpstops - bottoming out causes huge snap oversteer. Often with stiff dampers and Combe having a number of very long rights it eventually compresses the damper right up - therefore it needs stiffer bars to stop the damper compressing (in reality thats a totally backwards way to do it but with unwillingness of a lot to spend out £££ on uprated torsion bars its how it happens - with IRS on say a Golf they'd always change rear springs with fronts!).

 

Other things to try are a lesser spring on front as again you don't have enough rear spring, better tyres as higher spring rates make good work of slicks, and also finally dropping the damping down further.

[Jonmurgie 2]

300lb springs up front is VERY hard for a 205/309... and the F1's probay overheated as it was a warm day (at least it was in Cheltenham).

 

Also, what Toe are you running, if it's anything other than 0 then that probably didn't help either!

[crogthomas 0]

Are all the dampers adjustable? The first thing to do would be to back them all off to the softest setting and then try it (front first, then back). Then start to think about making changes to spring rates and ride heights.

The key is to make changes one at a time and take detailed notes about how it felt and how lap times changed.

 

Craig

[TEKNOPUG 3]

As said, the stiff front end will promote understeer.

[Rippthrough 98]

As said, the stiff front end will promote understeer.

 

 

And the overly stiff rear dampers will give the snap oversteer.

[Butler 0]

Do you have a cage?

[taylorspug 7]

First of all get some softer front springs, 300lbs is pretty excessive for road tyres. Have you got the facility to run any caster on the car? Running some negative caster will help the car no end, as it will provide some negative camber on the outside wheel as you turn through a corner, and positive camber on the inside wheel-perfect for getting the car to turn.

 

Im not experienced specifically in setting a 205 up for track use, but that is what i would say was a good starting point. Also maybe solid rear beam mounts would steady up the rear end somewhat?

 

Whatever you do change one thing at a time, so you know what effect any changes have made on their own!

[Anthony 1,000]

Pretty sure from my passenger ride in it that it's too hard on the front, and certainly the handling seemed awful from where I was sat as I said at the time - just seemed to understeer everywhere and refused to slide the tail out regardless.

 

The difference between the handling on yours and mine (basically standard except for Bilstein Sport dampers) was night and day - mine felt somewhat soft on track as you'd expect, but was perfectly balanced and progressive on the limit.

[Batfink 201]

you have an unbalanced car. Your torsion bars do not match the stiff suspension up front so you have dodgy handling. THe car will predominantly understeer due to stiff front shocks and when you lift off has massive weight transfer to the front due to the soft rear.

[Sandy 191]

I'm running:

 

Front: 225lb/inch springs, ~260/120 bilstein inserts, no ARB, eccentric mounts set half way between maximum castor and neg camber, parallel toe standard track.

 

Rear: 22mm bars, Challenge bilstein dampers, 20mm ARB, solid mounts, ZX arms (1 degree neg camber and parallel toe), standard track.

 

It felt extremely stable and balanced in the corners and the slight oversteer on entry was predictable and useful, blending nicely to slight understeer under power, pretty balanced. Very responsive through switchbacks. It was slightly nervous under braking, but the brakes are probably partly to blame for that. Colin Satchell said better rear damping control (upright dampers basically) and maybe a touch of rear toe in re-applied would stabilise it.

[veloce200 3]

I'm running:

 

Front: 225lb/inch springs, ~260/120 bilstein inserts, no ARB, eccentric mounts set half way between maximum castor and neg camber, parallel toe standard track.

 

Rear: 22mm bars, Challenge bilstein dampers, 20mm ARB, solid mounts, ZX arms (1 degree neg camber and parallel toe), standard track.

 

It felt extremely stable and balanced in the corners and the slight oversteer on entry was predictable and useful, blending nicely to slight understeer under power, pretty balanced. Very responsive through switchbacks. It was slightly nervous under braking, but the brakes are probably partly to blame for that. Colin Satchell said better rear damping control (upright dampers basically) and maybe a touch of rear toe in re-applied would stabilise it.

 

 

I run 250lb front, plenty castor, 309 arms, std rear bars but 23mm arb - use selatex bumpstops to increase rear rate progressively. Balanced and possible to drift as well!