Derek Johnston Ferrari 458 GT Cup
Derek Johnston, experienced Sportscar and Radical Champion moved into GT cars with his Ferrari 430 Challenge spec car in 2010. Derek made his mark
with wins in the Pirelli Ferrari Open series and then moved up to a Ferrari 458 Challenge and across to the GT Cup series. With support from
Derek’s own MSW Steel business and preparation
by Graypaul Ferrari of Nottingham the scene was all set for some great racing.
After a chance conversation with Nigel Greensall, Derek’s driving coach and fellow Radical racer,
an opportunity to measure and analyse the Ferrari’s suspension came up thanks to Derek’s generosity and enthusiasm to get the best
from his car. The car was fast already, but a bit of a limit had been found with some understeer that so far had eluded any cure.
Some of the conventional cures for understeer had already been tried, and bigger tyres were not an option as the regs prescribe Pirelli slicks,
and nothing suitable was in their product range. We analysed wheel frequency to come up with the correct spring rates, and using the new
development on our system – damper rate prediction, we worked with the damper supplier on their dyno to get the settings into the
right range. With some mods to wheel geometry and alignment and a revised front anti-roll bar it was back to the track. Nigel’s
feedback had been invaluable in this process, but the important thing is to get the car to match the competence of the driver so that the
car/driver combination can be as quick as possible.
Using our deep experience in racecar handling and suspension systems and the range of systems and software we have available it is now a well
trodden path for us to identify problems or shortcomings in any racecar’s suspension system and redress these. Many sportscars
have suspension designed to be at home on the road rather than the track, with parameters more about production cost manufacturing, parts bin
engineering, and collision safety than lap time. Some existing race cars, particularly historics (or even just elderly!) have suspension designs
that don’t work well with modern race tyres or even modern road tyres, and of course some are just rubbish from the start! Even if a car
has good kinematics it is highly likely that the dynamics can be improved, balanced front to rear and brought in line with driver ability.
The results speak for themselves, Derek has just (October 2012) clinched the Bute GT Cup overall title
in competition with a number of custom built GT cars, regularly beating some very fast competitors such as Moslers, Ginettas, Porsches,
and other Ferraris... Much of the success of this car is down to the superb level of preparation by the
Graypaul Ferrai Race Team and in particular to
of the Year Dean Pallet who has been meticulous in his attention to detail and very positive about our contribution to the team effort,
There is still much more pace to come from the car, and the decision about which series to campaign next season has still to be made,
so watch out for this very fast car and driver combination in 2013.