Getting serious with the handling...

Soldato
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While the new ~400bhp engine is still waiting for a couple of parts and waiting for me to find time to port the head I am looking at improving the handling further.

On Saturday I travelled up to Yorkshire to leave my car with a company called "Cornering Force" who are working with Spitfire Engineering to develop a blade style antirollbar and possibly a rear antirollbar as well.

All Cornering Force do is advise on suspension setup, mainly for race teams. Their premises aren't really a garage in the conventional sense, there are more laptops and computers there than tools!

One of the benefits of a blade ARB is that it can be adjusted easily using a nob or similar to give very small increments of adjustment, similar to how most adjustable shocks work. It can even be engineered so that the stiffness can be adjusted from the cabin whilst driving.

As part of this exercise the car is going to have pretty extensive datalogging and benchmarking to determine the absolute optimal springweights on the latest spec Nitrons, the ideal valving and of course the optimal range of operation for the ARB. This will involve extensive track testing which I'll get to try once it's all done.

We concentrate on vehicle performance with some Driver performance measures. The data that we typically gather includes;

•Longitudinal/lateral/vertical acceleration
•Inner/middle and outer temperature on each tyre
•Steering angle
•Damper position and velocity
•Speed, track position and lap times using GPS
•Yaw rate

Analysis of this data using sophisticated software enables us to understand how the setup is working on a corner-by-corner basis and help us to optimise;

•Camber and tracking
•Tyre pressures
•Balance for over/under steer at different stages of a corner
•Damper settings
•Tyre operating temperatures

What we check as standard…
Dampers We dyno each damper at current setting and full soft/full hard settings. Provide Force/Velocity and Force/Displacement curves for report (with other curves available on request). We calculate the theoretical optimum damping rates and comment on the suitability of the current settings.
Springs We test the rate of each spring. We calculate the Ride Frequency provided by these springs and comment on their suitability.
Anti-roll bars We measure the rate of each ARB and calculate the combined roll-resistance provided by the springs/ARBs. We assess the suitability of the spring/ARB combination.
Corner Weights We measure the individual corner weights, the sprung and the unsprung weights. We measure the C of G of the sprung mass.
Geometry We measure the camber, caster, tracking and suspension geometry then calculate the effect of both bump and roll on the geometry using kinematics analysis software. We calculate the Kinematic Roll Centre height using analysis software.

Their inclination at the moment is that my car is too heavily sprung and that a stiffer ARB will allow for softer springs with no compromise in performance.

As a result of the testing I'll get a report on the ideal rideheight, geo, spring weights, ARB stiffness, damping, tyre pressures etc. Pretty much going to town on the entire ride and handling setup. The intention is to produce a handling pack as a result, which will only work as a complete unit given a specified set of wheels, tyres and alignment.

No one else has gone through this degree of testing on the Elise that I know of, and certainly not the VX as it doesn't come cheap. By monitoring the real time temperature across the width of the tyre it's possible to see how hard the tyres are being worked and to make the most effective use of the contact patch. For instance on saturday they showed me graphs of tyre temperature through a corner and from entry to exit the surface temperature changes from 50 degrees to 120 degrees, and back down again by the time you have exited the corner.

To be honest a lot of the principles they were trying to explain to me were way over my head, but Simon who runs the company is fanatical about suspension and the physics and engineering behind it.

The car is going to be there for about 3 weeks. First it's going to have some datalogging, involving tyre temperature monitoring and damper movement (with these cool little devices that track minute movement of the damper rod). Then it's off to the testrack for on track testing with a qualified racing driver.

All of this data is then used for calculations to work out the ideal settings which are applied and it's back to the test track again with the same driver for further testing, laptiming, datalogging and driver feedback. A few more tweaks and then I'll collect the car and have a session on the private test track with the racing driver to see what I think and also to get some tuition.
 
Very serious attitude indeed. I can't imagine that will be cheap? Have you thought about just driving it the way it is with the extra power and see what you think first?

Seems to me there is a huge amount of money being thrown at this project... it should be fantastic, but can't help thinking it might be a weeeee bit overkill.

Have you looked at any aero mods yet? I'm pretty sure the VX220 has a flat underbelly, but have you investigated how splitters, canards and a wing would help?
 
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Sounds awesome, would love to have similar done to our sprint car but I strongly suspect the cost would probably be more than we've spent on the entire car so far!
 
Sounds good, nice to see people doing things properly and not just thinking whack on some coilovers and it will be awesome.
 
salami - it's not really related to the power, I've got my second set of Nitrons on which whilst are an improvement I'm not sure it's made it as compliant as I'd like for the road.

It's not really going to cost me anything at all, other than time, travelling, time without the car and a few other bits. It's another one of those development things where the company doing it is equally as keen to do it as I am for them to do it. It may also appear as a feature in a magazine too. No doubt the true cost would be several thousand pounds.

It's also being done to prove a point that you can't just change one component in isolation without really testing what it actually does to the car. There must be no end of manufacturers selling suspension upgrades that either don't work or aren't as good as they could be because they haven't gone to the lengths to really see how the car responds in a scientific manner.
 
Also, is there a particular problem with the handling you want to 'improve'?

Edit // Just read that they're using your car as a development car. Excellent stuff, and I hope you end up with a great end result.

So you're running this as street car?
 
All well and good until you get a fat passenger and need to recalibrate the lot ;)

I cant help but think its going very OTT now for a fast road/track car, but respect for doing it none the less.
 
Also, is there a particular problem with the handling you want to 'improve'?

No, not as such, other than how the car responds to poorer road surfaces. The exercise is to take a very good aftermarket setup (new nitrons, TD1.2s, R888s, Spitfire subframe brace) and see just how good it is and how much better it can be made.

For one reason or another I haven't spent a "silly" amount on the car.
 
All well and good until you get a fat passenger and need to recalibrate the lot ;)

I cant help but think its going very OTT now for a fast road/track car, but respect for doing it none the less.

It isn't really that OTT for them when you consider it's what they do exclusively. You can't change anything with any certainty, nor get proof that it works if you don't test it thoroughly. They're confident that there's such an enormous difference between getting it just right and being slightly off that it's worth doing.
 
Aero mods? (not to improve the damping), as a seperate issue I mean.

Probably not, possibly a diffuser but I don't really want a wing. It's one of those things which is a bit "lick your finger and stick it in the air" unless you go to a wind tunnel like a mate did with his Exige. To get any meaningful improvement the wing needs to be pretty enormous and that's a step to far for me in a road car.
 
Can I just ask, what will the ride be after all of this? Is it going to be spine-jarringly stiff, comfortable or somewhere in between?

I want it more comfortable. It will be setup as road/track car, certainly not like a racing car that will only go on billiard table smooth surfaces. The problem with bone jarringly stiff such as when the car is over sprung is that the tyre is battling to stay in contact with the road surface over bumps so you are wasting grip anyway.
 
One of the benefits of a blade ARB is that it can be adjusted easily using a nob or similar to give very small increments of adjustment, similar to how most adjustable shocks work. It can even be engineered so that the stiffness can be adjusted from the cabin whilst driving.
How would that work? :confused:

If they're adding a blade style ARB then once they've set it exactly right the last thing you want to do is adjust it, unless they design it so that the two main settings are perfectly suited to the car. 'hard' position for track use, and then the 'soft' position for road use. :cool:
 
How would that work? :confused:

If they're adding a blade style ARB then once they've set it exactly right the last thing you want to do is adjust it, unless they design it so that the two main settings are perfectly suited to the car. 'hard' position for track use, and then the 'soft' position for road use. :cool:

For most people it's not an issue, but those racing may want to change the stiffness on a corner by corner basis.
 
For most people it's not an issue, but those racing may want to change the stiffness on a corner by corner basis.

What I mean is, how would a blade style ARB be adjusted like that. Adding an actuator onto the end of the ARB arm? Would add a fair bit of weight. :confused:
 
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