what is the difference between the 6 pot and the 4 pot brake system. going to get the wilwoods but having trouble deciding which one to get.

 

6 piston
more expensive, more pistons, bigger disk... if you're not tracking you don't need either....

 

go 12

 

qft

on a car as light as the fit, 4 pot fronts with even single rears would be amazing but ridiculous...

some oem+ 2 piston calipers would be more than adequate with the rear drums...

good pads, rotors, and fluid is the biggest difference you can make... extra pistons won't clamp any harder, but clamps a slightly larger pad more evenly...

 

Don't forget about brake bias. The rears already do nothing in these cars. Increasing the braking force of the front is just going to exaggerate this problem making brake modulation even more difficult. Since these cars come with stock ABS you won't flat spot your tires, but expect them to have even less life and you will nose dive the car even more now. Braking distance might actually increase because the tires can only grip so much before losing traction you want to use all 4 tires to stop as much as possible not just your fronts. Someone should make an after market rear bias, but this might screw with the stock abs system and I would not began to know how to adjust it since you need the tires to lock up in order to know what the correct adjustment is.

 

QFT.

The OP has a GD, so a rear-disc conversion would be possible. If this was done, then it's just a matter of experimenting with higher friction brake pads on the rear to increase the rear bias to a point where optimal performance is reached. This could be combined with a 4-pot upgrade up front as well to increase the feel / modulation.

Although this would be a LOT of work and a very expensive proposition.

For the OP, Stoptech has an excellent article on brake bias and why it is important. StopTech : Balanced Brake Upgrades