The Performance Curve
The car is now running and at the tuning and tweaking stage. At this early point the chassis set up is so bad that a simple touch on the throttle can plough it into a ditch or hedge.
The feel of the clutch is good although the biting point makes the peddle long for quick gear changes.
The Brake peddle is a little spongy although there is no trace of air in the system and the peddle is neither long or suffers pump.
The throttle peddle for me is good smooth and precise, although others have commented that it is too close to the foot well hence difficult to find at first. Once accustom everyone agrees that the action is extremely precise, which is good.
The chassis is far from set up and progress on this will take time, especially running time. The feel is VERY hard with zero body roll and spine crushing pot hole coverage (at present a pot hole is anything 25mm lower that the road surface). With the original B204 sump still fitted the ride height is high and forcing the suspension to be stiff and limited. Once lowered the car will soften and the cornering chatter should be eliminated.
Wheel alignment and camber are still far from perfect although self centring of the steering is good. With cornering chatter and wheel alignment errors to resolve any aggressive power causes alarming results.
The brake bias is another on going adjustment, at the present time the rear bias is good in respect that the front locks up before the rear, although some more rear stoppage would be welcome. Braking is very very rapid as you would expect from such a lightweight car. 4 point harnesses are a must when a full brake test is tried or the steering wheel becomes a very solid air bag!
The major problem seems to be over heating so some bigger discs and hence callipers looks like a future investment.
The real bonus during this set up process is the flexibility of T5 suit in engine management. Being able to run from 185BHP to 330BHP by plugging in a laptop has saved many body repairs (both human and automotive). To move above 330BHP means hardware mods so for the time being the big injectors and turbo will remain in their boxes and the exhaust resonant silencer and CAT will remain in place.
With induction filters, big intake pipes and large bore short exhaust gas flowed head and mega software already giving this car enormous capabilities.
With the dash speedometer presently way out of calibration, a cheap, easy to configure KPH speed sensor is being used. So all of the following is in KPH. The BHP figures have not been tested on a rolling road but are calculated from all the known parameters and should be within +/-
Power settings available 185, 220, 290, 330.
(For those with out calculators 100KPH = 62MPH)
At the end of two days of testing to obtain the above results, the brake pads had glazed the rears especially showing the rear end braking is insufficient just allowing friction burn and not stopping power. The front discs showed signs of blueing indicating they were unable to dissipate sufficient heat. So brake bias adjustments would be required and, as stated before, a big brake set up has been placed on the wish list.
Performance testing shall now be put on hold until the new sump has been fitted so that more chassis tuning can be accomplished as the use of anything above 220BHP is extremely dodgy right now.
Tweaking and Tuning
First Job is to revamp the rear brakes so new callipers have been fitted mainly to improve the handbrake performance. Simple job and much improved performance has been achieved.
Then it’s time to attack the front “No Go” peddle. After reviewing the options available and the cost implications the best value stopping power seems to be the Wilwood Midilite 4 pot callipers, Wilwood pads with a bigger 285mm x 24mm (original 257 x 21mm) vented disc on each side. Extra stopping power with better heat dissipation should be a good double bonus.
After a super fast delivery of the complete kit, all looked good until it came to fitting them.
OK hit the phone. Find out that the callipers are wrong for the disc coz the kit has been mixed up. Then we find out that on occasion the calliper mounting holes need to be drilled out coz they are sometimes to tight.
Excuse me but at £500+ you would hope that the damn things were finished. I can cope with a kit mix up coz we all make mistakes but having to take a drill to finish a product of this supposed value.
Me says NOOOOOO!!!!
But for service and support I can't fault Rally Design so far. New callipers pre-
New callipers arrived and apart from the need for a front mounting shim on top of the existing 18mm spacer all is well. Brake bleeding takes an age, you need plenty of fluid available to get these four pots fully purged.
The end result looks impressive, so let hope the improvement in stopping power is equally as nice. Time will tell.
Original Front Stoppers
Wilwood Front Stoppers
After 2 two weeks at Abbott Racing the car has returned with the front end geometry sorted and the rear end half sorted. With a rear toe in of 2.75 degrees some shimming work is required to sort this out. Doing some trigonometry calculations has determined that around 1.5mm & 2.0mm shims will be required on the front side of the upright. All the corner weights have now been determined and suspension settings have been tweaked and tucked. The car feels much more confident not only on the road but, after them that know have pawed over it, in the drivers mind as well.
With the rear end sorted strangely the car is slower now it’s balanced, than it was initially. Not only does the razor edge twitchy ness been tamed but so has the knife edge performance. The whole car has mellowed and can be tightly controlled, this means that the driver has to do a lot more of the work, rather than just hanging on to a raging beast. Over time this will make for a very very fast car in all aspects, acceleration, braking and most importantly handling.
Runs with 300BHP were all scrapped as wheel spin just eat great chunks of time. Some more software work is required before this power can be used for standing starts. In full flight the 300BHP+ settings are mind blowing! The roll bar meets the rear of the crash helmet in mind numbing repetitiveness on each and EVERY gear change.