Getting serious with the handling...

Half the Elise's problems when it comes to pot holes is the stiffness of the standard ARB. It turns one wheel's drop into and out of a pot hole into a major event involving the opposite wheel as well. Resulting in a skittish feel and lesser confidence.

Though I'm obviously not an expert I don't really see how adding softer springs/dampers and a stiffer ARB is going to make it better.

I'd be treating this company very suspiciously if it were me. Some backstreet garage just isn't going to know more than Lotus I'm afraid.
 
On that basis would you say that there are no worthwhile upgrades to any of the tyres, wheels, geometry settings or suspension on any Lotus model?

Of course there are, because as standard everything is built to a price and to sell in the highest number possible.

Seriously, this guy really knows what he's talking about, he's an engineer, not a mechanic. The cars he usually works on are worth, far, far in excess of the VX, some very rare and expensive race cars.

I don't think your comment about the ARB is entirely correct either, it's far more complicated than that.
 
Driver impressions were that the car turned in nicely but under steered considerably through the apex and exit. Although it was clearly sprung hard it did not seem unduly harsh on the track. However, this car is used on the road as well as for track days and we understand that it feels nervous and jittery on the road.
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The analysis of the set-up shows that;
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§******** The ride frequency is very high for this type of car.
§******** The damping F/V curves have some issues.
§******** The anti-roll bar provides a very low proportion of the roll resistance.
§******** The percentage of the total roll resistance at the front is low.
§******** The amount of roll (degrees per g of cornering force) looks about right.
§******** Corner weights show a considerable wedge
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The analysis of the run data shows that;
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The front tyres need a little more camber but the pressure was good.
The rear tyres need less pressure but the camber was good.
Tyres are running at 80-90oc in corners
The car rolls about 0.9o/g in corners
The car achieves a max of 1g lateral acceleration in corners
The car achieves a max of 0.68g in braking/0.46g accelerating in 2nd.
The damping bump/rebound balance needs some adjustment.
Max front damper displacement is 22mm rebound/16mm bump
Max rear damper displacement is 31mm rebound/36mm bump
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Based on this I have a few recommendations;
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Reduce the spring rate and increase the ARB rate to make the car less harsh on the road but keep the same overall roll angle per g of cornering force.
Fit an adjustable front ARB to allow quick adjustment for preference on the track and the road.
Adjust the damping rates for the new spring rates.
Adjust the corner weights
Adjust front camber.
Lower rear tyre pressure.
Probably increase the ride height a little bit but play with this during testing.
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I am keen to make these changes as I feel that we can make the car a better compromise between road/track use and improve the grip without losing responsiveness. We can address the mid corner-exit understeer with these changes.
Click to expand...
 
Here's what I posted on the VX site straight after the Bedford Trackday.

So I have played around with quite a few things. With both sets of Nitrons I had thus far I was never really happy with how they performed on the road, it always felt like the suspension wasn't really "working" to deal with bumps and changes in the surface, on some roads the car would feel very skittish and never as sure footed as I thought it could be. On one particular straight piece of road near me I could probably do 80mph easily in my Golf but the VX would feel distinctly out of control at 60mph, crashing over bumps.

The way the car performed on saturday was just stunning, the ride is so much more compliant with considerably softer springs but the amount of body roll feels even less than before. It remains so responsive to changes in direction and the traction out of corners is just something else. On a cold and wet/damp track with R888s there was so much traction, the power just went down so easily, it was so stable and composed. The balance through the corners was just beautiful. It was clear through the morning that we were just reeling in pretty much every car there and carrying so much more speed through the corners and getting on the power so much earlier on the exit. One notable thing was Charlie (the racing driver/instructor) was telling me to turn into the apex more on some corners that I had got my entry line wrong on, which I wasn't doing because I didn't even think the front end would be able to grip and turn in at that speed and in those conditions as before it would just wash out with understeer but now it just digs in and grips, it was completely neutral.

By altering the front ARB it was so obvious how the balance of the car was subtley changing, moving from oversteer to understeer and via versa.

I think you kind of develop a good understanding of what the car is capable of when you have owned it for a while and tried various things but this just altered my perceptions, it's on completely a different level, I've never been in an Elise, Exige or VX which even came close to what mine seems to be able to do now. I just need a new engine to carrying on playing with it now!
Click to expand...

Oh and it's gone from 0.9 lateral G to 1.2 :D That's with no aero effect on road tyres.
 
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Sneak preview, should get some nice shots out of it hopefully.

13666_395707350200_506935200_10405679_6380687_n.jpg
 
WHOA! Holy pictures batman :D

EDIT - Oh, nice of them to leave your full name in the middle of that pc screenshot :o
 
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This is a really interesting read, thanks.

Like Neil I've been considering some Nitrons, but from your experience it sounds like £1100 on shocks is wasted without the other changes.

...I'll need to carry on saving then..!
 
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