Sunday, 26 February 2012

Snetterton Shakedown

On Friday 24th Feb after a 5.30am wake-up we headed over to an open-pit lane trackday day at Snetterton for our shakedown test.
At the briefing meeting the organiser commented that the paddock resembled a race meeting rather than a track day due to the number and range of race cars participating. 

Everything from Ford Fiesta's to Britcar Ferrari's and Aston Martin's to Radical's were present and running on track together with an array of road cars.
After the mandatory sighting laps we got out on track and the car proved to be mechanically sound.  There were a lot of significantly faster cars on track so getting a clear set of laps wasn't possible until later in day.  Initially we had quite a lot of understeer which was reduced by lowering the front ride height and increasing the suspension stiffness.  We also dropped the tyre pressures consitently throughout the day.
Whilst still being reasonably slow compared to race times we did improve both car and driving ability significantly throughout the day.  Fuel usage was over 1 litre per lap over the approx 45 laps we completed.  A positive note was that the stopping power of the Brembo brakes and race pads was excellent.  We did manage to overheat the brakes at one point which will require a change of actual fluid and we will also upgrade to more expensive racing fluid at the same time.

Alignment and Camber Setup

After changing the suspensiona lot of toe on the front and rear was induced, which had to be reset.  We used the DIY string method to measure the alignment knowing that we just wanted to get it roughly aligned initially. The wider rear track of the Boxster and narrowing body lines are deceptive when you look at the alignment by eye.

First we set the ride height getting the car level all round. This is done using the adjustable spring perches on the suspension and measuring the ride height under each jacking point. 
We then setup equal length parallel fishing lines running down the side of the car, equidistant across the front and back.  We measured the distance between the front and rear rim of each wheel and the parallel line - the difference being any toe in or out.

After several adjustments we managed to get the alignment where we wanted it (which is not far off 0 / straight) and also maintained a good amount of camber (-3 degrees on the rear and -1.75 degrees on the front).  

Adjustable 911 GT3 lower arms are an option to achieve more front end camber - but these remain a luxury (that we can't currently afford).

Seats & Harnesses

With the dashboard and instruments back in place the car re-started first time which was very good news. i.e. We had re-connected all the wiring and not cut out anything too important!

Focus turned to re-fitting the seats.  The bolts for these are very awkward to reach now the roll cage is in place.  
 Luke 3" wide 6 point FIA spec harnesses have been installed and adjusted to fit.  Roll cage padding has been placed in a few areas to stop us baning our heads/helmets on the roll cage and provide a little bid of elbow padding.

A removable steering wheel boss has also been added to make getting in and out of the car easier.