Getting rid of that nasty understeer

[MickOpalak]

Even with the LSS I still find that my Elise has more understeer than I'd like.

Can anyone recommend what tire pressures to run at to remove as much understeer and possible?

What about alignment? Can someone recommend some alignment specs that will remove the understeer? More toe out in front, I imagine. Anything else?

Is the understeer an inherent characteristic of the rear weight bias? Not enough weight over the front wheels?

[008]

Putting aside driving style, try 32 hot and as much negative camber as you can get in the front. Balance it according to what track you're running because I haven't seen an Elise yet that has equal amounts.

[adamant]

If you're comfortable with it, remove all the front camber shims, that should help a lot. I dont think you can get wider tyres than LSS up front. I am going to wait till sprig before setting up mine. Too much salt and snow here right now.

I put 245's all round and 1 deg neg camber on my Boxster. That made it wonderfully neutral on the track.

[MickOpalak]

Originally posted by 008
Putting aside driving style, try 32 hot and as much negative camber as you can get in the front. Balance it according to what track you're running because I haven't seen an Elise yet that has equal amounts.

What about rear tire pressure?

Does anyone know the official factory alignment specs for the LSS? Are they in the owners manual?

[meat]

28 hot all around is what you want, maybe as high as 32 to give you a bit more tire life.

More neg camber, as mentioned, will help as well.

[Evl]

Originally posted by MickOpalak
What about rear tire pressure?

Does anyone know the official factory alignment specs for the LSS? Are they in the owners manual?

Yes, it is in the manual right before the index, but I don't have mine at work.

[008]

Originally posted by MickOpalak
What about rear tire pressure?

Does anyone know the official factory alignment specs for the LSS? Are they in the owners manual?

Last event I wound up with 32 front and 33 rear hot. It was about 55 degrees ambient. Worked nicely for me, I'll try 28 and in between this week. Should be warmer.

[Surferjer]

I felt like I was driving a snow plow this weekend at the very wet autoX. At one point I took out a whole row of cones because the car simply wouldn't turn. I was running much lower pressures, and a 2 lb offset. I will have to try it with higher pressure next time.

[khamai]

Surferjer

Typically you lower PSI in cold or wet conditions. This is to try to get more mechanical grip from the tires and build heat more quickly.

You're less likely to roll the tire over in the wet since there's less grip, thus you can run lower pressures.

Kiyoshi

[Randy Chase]

My take though, is if it is standing water, I raise the pressures, because heating the tires in a rained out autocross is not going to happen. I want to shed as much water and be a skinny tire.

I think in a wet autocross, the main thing is one needs to use more brakes earlier. Otherwise it creates too much understeer.

[sleepless]

Originally posted by Randy Chase
My take though, is if it is standing water, I raise the pressures, because heating the tires in a rained out autocross is not going to happen. I want to shed as much water and be a skinny tire.

Ditto for road courses...

[sleepless]

Originally posted by MickOpalak
Is the understeer an inherent characteristic of the rear weight bias? Not enough weight over the front wheels?

Generally speaking, yes.

I'm assuming you're getting the understeer mid-corner when turning in. You can easily use the throttle to rotate the car. Either lift a tiny bit to put weight on the fronts, or, if you are comfortable with it, add throttle for a little rear rotation.

[khamai]

Yes, Randy is correct about standing water for most tires that have a lot of tread. The concept is to stiffen the tire structure and keep the tread more open to cut thru the water.

This all goes out the window with slicks or near slicks. It would be interesting to see what the 048s like better higher or lower pressures in the wet. Of course what idiot would be racing in the rain on slicks? Me?

I should have correctly stated that in damp conditions go lower.

Kiyoshi

[Randy Chase]

Originally posted by sleepless
Generally speaking, yes.

I'm assuming you're getting the understeer mid-corner when turning in. You can easily use the throttle to rotate the car. Either lift a tiny bit to put weight on the fronts, or, if you are comfortable with it, add throttle for a little rear rotation.

Yes..... you have to drive it differently.

In very wet conditions, it becomes more point and shoot, with rear end control using throttle. It can be a lot of fun.

But braking should only be done in a straight line in the wet. Well, if you want to turn.

[Randy Chase]

Originally posted by khamai

I should have correctly stated that in damp conditions go lower.

Kiyoshi

I knew you knew that... just wanted to make sure it was clear to others.

[Randy Chase]

Back to the subject at hand...getting rid of understeer. My main point will still have to be to brake earlier and watch your slip angles vs throttle.

But.. you can dial in as much negative camber on the front... and more toe out. That will help. I think the Elise is a little skittery on the road, so be careful about toe out. I settled on zero toe for the front. Maybe I might try a hair out.

The other method involves making the rear less grippy, which I don't normally like to do. A car that understeers a little in the slow (or wet!) will be a faster car overall. But if one really hated the understeer...

Reduce the front swaybar.
Increase rear tire pressure past optimum.
Toe OUT on the rear

P.S. Mick, you were riding with me as a passenger on the Dragon. I never felt understeer as a problem in the corners. I did get some oversteer a couple times.

[Surferjer]

With my lack of experience I was trying to trail brake in the wet. Umm, that doesn't work so good, as course workers will attest. . I was running 23 and 25 front to back, the ground was damp but the rain had stopped and there weren't visable puddles. Still, the car wanted to slide in the cold damp. A lot. Good advice on braking early.

[Surferjer]

Dumb question, but...are we better off with Hoosiers, AO48s or AD07s in the cold damp? What about rain? Puddles? Any thoughts? Perhaps if someone could rank them for each condition. Thanks all.

Edit: I'm referring to autoxing, which I think is obvious, but...

[thegit]

Originally posted by MyElise


You can get this car to rotate with both power and lift. Figuring out which to use when is the fun part.

Problem solved.
m

[Randy Chase]

Originally posted by Surferjer
Dumb question, but...are we better off with Hoosiers, AO48s or AD07s in the cold damp? What about rain? Puddles? Any thoughts? Perhaps if someone could rank them for each condition. Thanks all.

Edit: I'm referring to autoxing, which I think is obvious, but...

Grippy is still grippy. Standing water calls for treaded tires. Damp I would go with Hoosiers and adjust my driving. You may be surprised at how wet it can be and the Hoosiers will still be faster.