Hi all, I do not write here so much but I read this very interesting forum every day.
I use my Lotus only for trackdays on the whole continental europe, but I would like to plan in the future a week in Uk to experience your beautiful circuits.
I would like to share with you my thoughts on the geo settings. I have a n/a Exige with Nitron suspensions (425-550) usually at +5 clicks front and +8 clicks rear from the all hard.
My geo settings are front camber -1.0 (zero shims) and zero toe, on the rear i have -2.2 camber and 3mm total toe in.
Tyres are the usual A048 but I am planning to switch to Toyo R888 as here in Italy the A048 are difficult to find and really expensive.
The ride height are 11.5cm front, 12.0cm back.
My question is on the total toe in at the rear. The car is very neutral, it is quite impossible to go on oversteer even on low gear in tight corners or to have wheelspin, the unique “imbalance” is when you put too much speed at the corner entry and in fact few times I had a tailspin (for example at the entry of the new last chicane in Spa).
My issue is that the speed/acceleration of the car is very difficult to gain with in 4th or 5th gear, mainly I guess for the areodinamic drag but even in my opinion for the toe in which is a drag also. I have to point out that I changed also the final drive with a better 4.80 so now the car has a better acceleration but in 5th gear on circuit the situation is not improved so much, that’s why my thoughts are on the toe in which seems to me still too much in.
I am wondering to open it a little bit more (I began with 4mm total toe in the past) and maybe trying with 1mm total toe in.
It would be a good idea?
Which are your best geo settings so far?
Rear toe seems about right 1.5 to 2.5 mm either side, 3 to 5 total.
Even if you set it to zero I doubt that you would see any noticeable difference in 5th gear acceleration.
By the time you are in 5th you are doing 115 to 120 mph. At that speed it is the aero drag that is the big issue.
Options are to add more power, or somehow smooth the car. Lose the wing, smaller mirrors, close up the front ducts. See how the second generation GT3 had a much smoother appearance.
Do you have uneven tyre wear? You could play around with tyre pressure to get more grip.
As you seem to have “problems” with high speed cornering stability I would be careful to remove the wing. I’m not sure with the S2 but in the S1 the wing contributes to a lot of downforce.
Have you done any other changes? Opened the rear up to get heat out? A lot of the S1 owners open the rear clam up to get heat out but the negative effect of more airflow through the car is a potential loss in rear axle downforce. Adding a proper diffuser will hopefully balance my car out
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Well the issue it is only the straight line speed and I understand that you are telling me what I was supposing, so that the areodinamic drag is the main problem. I did not do any other changes on the car so the rear diffuser is it his place.
I usually go with 26 psi with hot tyres, so I began the day with less pressure and then at every pit I deflate to join the 26psi.
I understand the only cure it is to go to Komo-Tec
If you think thats worth the ����
Remember the discussion we had about the Kemmel Straight how 115-120mph was all that I found achievable. I mean my car runs alot of down force I know, good weight saving with a handy set up but the only way I’ll improve the straight line speed is with more power and lesser weight. If I was looking to decrease my ride height could I just change the springs on my Ohlins and to what…I only ask because high speed cornering is where I’m the most edgy. Alex your setup sounds excellent, Evo’s is brilliant…all I need is a set of balls like his and I’m sorted…can you get those from Hanger111
Yes the Kemmel straight is awful with a n/a exige but anyway the rest fo the lap is always great fun