We were invited by Jaguar World magazine to attend a test day at Mallory park recently.

The weather was attrocious but the XKR performed exceptionally well and was driven by a professional racing driver who was impressed with the Jaguars improved handling dynamics.

Following on from our theoretical suspension calculations, we took the car to Brands Hatch circuit for testing and fine tuning the of the geometry.

We used the Race Logic V Box for data logging/capture so that we could accurately analyse the results. The data from the V Box showed that the car was still showing strong lap times even though the drivers were still getting to grips with the significant and fundamental changes that we had made.

The car was pulling more G’s than we had expected through certain corners which led to uneven tyre temperatures, so we implemented a geometry correction to compensate for this.

With some subtle tweaking of the ant roll bar lever lengths and damper rates to suit the pilots style of driving, the car was now ready to go racing!

The revised suspension has resulted in the car being 2 seconds per lap quicker over it’s previous best times, which we consider to be a resounding success.

These components along with other more road orientate suspensension parts are available for sale and can be see at: http://www.tdi-plc.com/catalog/index.php?cPath=107_108_332_333_342

Based on the result of the calculations from the mathematical model, we modified the ride heights, spring pre-load and roll bar leverage to provide a weight distribution variance of no more than 5% at 1G force. This was calculated to make the car “easy” to drive.

At this point the car has an ideal “workshop” set up and is ready to be tested at the track.

We installed the TEIN Super racing suspension components and set the ride to the calculated optimum heights.

We then measured the static weight distribution for the chassis alone and then with the simulated weights of the driver and heavy fuel loads.

Armed with this information we were then able to calculate the Dynamic Index for all possible load conditions.

The next step was to piece together all of the data into one linear mathematical model in order to estimate how the chassis would distribute ground pressure when operating at G Force conditions.

To provide a clear path forward of improving the handing dynamics of the Honda Integra Type R for racing purposes, we needed to have a thorough understanding of the car and it’s suspension.

We started off by undertaking accurate measurements of the wheel base, track widths, suspension arm lengths, roll bar diameters and lever arm lengths, spring rates and suspension travel.

The next process was to calculate the roll centres and vertical centre of gravity through the chassis, and from this we were able to derive a theoretical base ride height from which we could develop further on the track. Following on from this we calculated an ideal spring and damper rate which TEIN were able to provide us with to special order.

These components can be bought at http://www.tdi-plc.com/catalog/index.php?cPath=107_108_332_333_342

Very experienced racers Nigel Ainge and Alan Broad are running a Honda Integra Type R in Britcar Production S1 and 24 hours, and Tin Tops race series this year.

Having been happy with an engine performance upgrade we had previously completed, they approached us for our views on improving the Mugen suspension kit that was already fitted.