GT understeer??

[REGGY5GT]

Is there any way to reduce the understeer on the gt?? i was told by the little italian bloke at cgb to fit a renault 9 or 11 arb but couldnt remember exactly what he said, any advice appreciated:)

[GTphil]

Not sure about the arb, but to avoid understeer I generally just avoid corners!!;)

Or come off the gas and counter it with a bit of lift off oversteer.:smokin:

[Sam Fish]

Give it some toe out on the rear somehow and make it stiff on the back. Usually works with FWD hatches.

[Renault 5 GT Turbo]

Give it some toe out on the rear somehow and make it stiff on the back. Usually works with FWD hatches.

Yes get your tracking set up and ask for 1degree of tow out. You can also increase the pressure in your rear tyres, turn in to corners earlier at a higher speed and come off the throttle for lift off oversteer to tighten your line.

This has got to be one of the most nervous handling fwd cars I've ever owned (even compared to the 205 1.9 GTi.

[Renault 5 GT Turbo]

Just noticed from your profile picture, your car looks low so you could consider increasing the height of the rear a touch.

[Tony Walker]

stiffening the rear improved turn in massively on mine.

[REGGY5GT]

ive got a set of dunlop gauges in the garage so ill set it up to toe out slightly, any advice on what to set it to for best results on the gt?? dont want it that far out its going to **** my toyos every 300 miles,lol. thanks

[REGGY5GT]

Yes get your tracking set up and ask for 1degree of tow out. You can also increase the pressure in your rear tyres, turn in to corners earlier at a higher speed and come off the throttle for lift off oversteer to tighten your line.

This has got to be one of the most nervous handling fwd cars I've ever owned (even compared to the 205 1.9 GTi.


my mistake, 1 degree out, thanks renault 5 gt turbo and others:agree:

[rikki GT]

Give it some toe out on the rear somehow and make it stiff on the back. Usually works with FWD hatches.


how do you adjust tow in/out on the rear?

[Matt@CodeRedMotorsports]

With difficulty, some heat, a hydraulic porta-power and probably a spare rear beam if it all goes wrong.;)

[Tony Walker]

1degree tow out? thats alot for road use imo, much more than 30mins scrubs tyres.

[Spooky]

I've never really had an issue with under steer and my car has always been stupendously low.

Like already mentioned, raise the rear and it will automatically improve the turn in and you will 'feel' the car wanting to under steer earlier helping you learn its behaviour.

Stiffening the rear damping will improve things too.

'Toe'ing' the rear out for road use is probably a pretty extreme measure and like Tony says, you will eat tyres on a regular basis!

[Woznaldo]

Even the best handling FWD cars will tend to understeer when pushed but learning how to drive the car will compensate a lot.

To reduce understeer you need to increase the grip at the front and/or reduce the grip at the rear (i.e. the front/rear grip ratio).

This can be done in a number of ways but, as the GTT has no adjustment at the rear, other than the afore mentioned 'heat and bend' method, you will need to play with the front end settings. I will also explain here that the addition of some rear toe out at the rear (heat and band) is effectively trying to get the back of the car to 'steer' itself out, much like how a skateboard turns, which aids turn in.

You can of course fit stiffer rear Torsion Bars but they are bit on the expensive side. Some have employed a different rear damper arrangement which replaces the rear damper with a coilover that is mounted vertically using a turret in the rear inner wheel arch. A low spring rate Spring can then be added to 'assist' the standard Torsion Bars.

As for the front, to increase the front end grip you can add some Negative Camber by either adding an Adjustable Top Mount which will allow you to push the strut tops closer together or by elongating the upper attachment bolt hole on the strut to hub mount. This will allow you to tilt the top of the hub in and thereby adding some negative camber.

The other area to look at is castor. More positive castor will improve initial 'turn in' by adding 'dynamic camber'. This means the amount of camber that is added/removed as the front wheels turn. The Cup cars used to mount the wishbone bushes further rear, effectively moving the wishbone forward. An Adjustable Top Mount would allow you to move the top of the strut rearwards which will achieve the same effect.

Reducing the damping effect and reducing the front roll stiffness can also reduce understeer.

Let me finally say that I am not an expert and there are many better qualified people within the club who can elaborate, correct or give you there own experiences from what works for them on the track.

[Matt@CodeRedMotorsports]

Nice one Woz. Good advise. BUT, we are all forgetting one thing here, how about better/grippier tyres? We must remember, the tyres are the only thing that connects your car and the road together, to steer, accelerate and brake. Improve these and you are halfway there.

[Woznaldo]

Nice one Woz. Good advise. BUT, we are all forgetting one thing here, how about better/grippier tyres? We must remember, the tyres are the only thing that connects your car and the road together, to steer, accelerate and brake. Improve these and you are halfway there.

Very good point Matt. My uncle got one of the first FIAT Strada Abarth 130TCs when they came out in '83/'84. He didn't want to mess with the brand new standard suspension to reduce understeer so he just fitted a really hard compound set of rear tyres, something BFGoodridge I think? Seemed to work quite well too.

Some FWD race cars use wider front tyres than rear, if the rules permit, to do the same.