by cat » Thu Mar 26, 2009 12:54 pm
If I may, a revised order (IMO).
Wilwood 4 pots and 300mm disks ~ £500 -----------GTO kit 4 pot 325mm disks ~ around £440
Hispec 4 pots with 300mm disks ~ £650
AP Racing 4 pots with 316mm disks ~ £950
Brembo 4 pots with 318mm disks ~ £750------------KAD 6 pots 330mm 2 piece ~ £1200----------Alcon 6 pots with 330mm disks ~ £600
AP Racing 4 pots with 330mm 2 piece disks ~ £1250
AP Racing 6 pots with 330mm 2 piece disks ~ £1500
(Note: the AP Racing four pots use different callipers for the 316mm and the 330mm)
I've pulled the KAD, Alcon and the GTO, kits to one side, due the lack of testing for the former and potential fitting problems on the latter, it’s would be difficult to place these at the moment. The KAD kit is very bling but so few have owned them judging their worth would be difficult, I would imagine calliper maintenance would be a monthly requirement for road use and getting a hard pedal with the small piston six pot calliper CNC'd from a billet made never happen, quite often CNC'd billet callipers suffer flex much more than forged callipers, the Hi-Spec kit is known for this on other models. Technically there is no Alcon kit as such, the calliper is a great quality Jaguar unit used on the XKR & S Vr range but the disk looks like it could be a lot lot better (looks like a Merc van disk). AP and Brembo dont make kits for the FTO (if they did the AP's would be over £2+) but thanks to the likes of ToneB and TheFreak we have thos options.
If any of the kits above require spacers or wheels with a bigger offset than 6mm then they will start to create handling problems, adding a spacer of significant thickness will create increased scrub radius which makes the steering woolly and numb, large spacers cause tracking to change during cornering causing tyre wear and less grip. Large spacers when combined with good brakes increase "Pull back" which is the front wheels toeing out under hard braking, large brakes cause this anyway but spacers don’t help it at all, under heavy braking a car experiencing pull back will try to escape right and left making it difficult to keep in a straight line, I have found a little toe in can help this.
{Boring stuff}
The is a huge myth that increasing disc size increases the braking force for a car, technically it does but in reality the difference in a 275mm disc and a 330mm disc will be immeasurable, what it does is improve heat dissipation and increase brake modulation, heat dissipation is obvious, the bigger disk can store up much more energy in heat and dispose of it quicker, brake modulation is the brakes ability to slow the car without the brake locking up. Even standard brakes have more than enough braking force to lock the wheels but the line of force required to do so from first applying the brake to it locking up is very short and steep, with a big brake kit like a 330mm four or six pot the line of force is much longer and much less steep allowing the brake to perform better, all the above only really has an effect if the tyres can grip the road, I have seen very expensive brakes on very cheap tyres a few times, what a waste of money.
I have always said the Wilwood kit is the brakes the FTO should have had from the factory, but if it had very few of us would be looking into the expensive brake upgrades and where would the fun be in that.