Geometry.

Topics relating to the Lotus Exige S2 (series 2)
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andybond
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Everyone seems to have their own closely guarded geo spec. I am finding on my AD08R that I am getting a touch of understeer when zooming along and hit a roundabout.

Anyone recommend some geo settings to work with?

For reference I am on nitrons and around 120mm height. 205 fronts and standard width rears.

I prefer a neutral corner rather than understeer or in fact oversteer.

Any advice is appreciated.
ade
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fit the bump steer reduction kit and consider running the front a little lower than the rear


finally make sure the tyre pressures are ok
Last edited by ade on Wed Jun 19, 2019 3:51 pm, edited 1 time in total.
ade
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andybond
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Thanks for that.

My front is a tiny bit lower than the rear.

Any offers / suggestions on toe etc?

Have a read the lotus 211 setup is good?
Fonzey
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Andy, these are the settings I've had on my two S2s. Very similar as you can see:

Image

On my Elise I had adjustable suspension and ran with a tiny bit of rake as you describe, I would describe that car as understeer on entry but very easy to balance it through the turn by adjusting the throttle. Inspired lots of confidence but not sure if that's what you're looking for.

On my Exige, I'm struggling with rear grip but have a very pointy front end. I believe this is down to my rear tyres being shagged - so that's being resolved before my next track day. It feels like the Exige will turn in to absolutely anything, but the rear doesn't agree - and often end up having to catch the car on entry which is knocking confidence and slowing me down a bit.

If I can get my Exige handling like my Elise did, I'm going to be a pretty happy boy - right now I feel I'm a bit slower in the corners and just making time up everywhere else... superchargers do that though I guess.
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andybond
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Thats very useful @Fonzey , thanks.

Your description seems exactly what I am experiencing with my exige at the minute - understeer on entry. I find that quite offputting. I dont want oversteer everywhere ( like my old c63! ) but I want a bit more direct / point with the front end.
Fonzey
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Maybe have a tinker with your tyre pressures before touching anything else, it's the easiest thing to do DIY I guess but harder to find a consistent point whilst driving on the road I suppose.

I've never run AD08Rs before so can't suggest any specifics - but just try dropping a bit of pressure from the fronts to see if that balances things up a bit.
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andybond
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Got cold 22F 24R at the moment. Ill double check them later this week
winthattt
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Andy,

You may find the attached an interesting read....

http://racingcardynamics.com/racing-tir ... ral-force/

The video is really illuminating!

It references Milliken and Milliken which is the bible for race car set up. You will see that slip and loss of grip is a bit of a misnomer. As suggested, tyres and pressures are a really good place to start as is geometry.

Keith
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andybond
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I shall watch with interest.

I would really like something go off though. I could tweak the pressures and never find the right setting due to it being a mile out.

Ill use the ones listed above and work with pressures.

I get *exactly* what is being said with the video listed above now.

Going to add a couple of pounds to see if its the lateral movement that I am experiencing.
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