My point though is that a properly designed BBK system doesn't need to add brake torque, its already easy enough to lock up the stock system, having too much brake torque is a bad thing without changing the master cylinder because the pedal travel will be greater than stock. I see no advantage to doing so then. Until a BBK company starts including larger MS's with their BBK, I'll continue to believe that extra brake torque via larger piston area is a bad idea.

 

Hai, didn't you just add ginourmous tires/wheels to your car? yes braking is limited to the tire you have. BUT just because you can lock them up, doesn't mean you can't benefit from better brakes. As there is a huge difference inbetween standing on your brakes and locking them up vs being able to modulate right up the limit and into the abs systems.

Plus you have put way bigger tires on, thus increasing the grip potential. Also even though you put quality wheels on, they are probably heavier then your stockers. Again putting more stress on your stock brakes. Can you stocks accomodate? yeah sure for 90% of the stuff we drive. But can the oem brakes be improved? You bet! In brake distance, greatly increased braking feel, fade resistance and bling

A bigger master cylinder is only needed if you greatly increase the piston areas of the front/rear calipers. If you just add a bunch of small pistons that have an area close to oem and use bigger rotors to increase brake torque, then you haven't stressed the master clyinder at all.

Remember, more pistons doesn't mean more area. Multipiston calipers greatly increase braking feel/modulation. Instead of your brakes being an on/off switch, they can be modulated closer to the limit vs oem single piston/dual piston units.

 

I'm not talking about stock brakes, I'm talking about BBK's. Braking modulation/feel is definetly a big plus for BBK's, more due to the added pistons on both sides of the caliper than the increased brake torque IMO. Adding a small amount of brake torque may be benefitial, but any substantial amount will affect the pedal travel negatively, that was my only point. A BBK can do all that you pointed out without changing the piston sizing, becuase the larger rotors usually used will increase brake torque to some extent because the point of contact is further from the center of rotation.

 

Adding a significant amount of brake torque via bigger piston area WILL affect brake pedal travel. yes that is true. But IMHO, most bbk systems use larger rotors to achieve this. Not piston area.

I think we are in agreement here.

 

Yes we are in agreement to some extent, you mentioned using larger piston area to increase brake torque though, which IMO is not a good way to go about doing so.

 

I don't see a problem with that if the increase is miniumal. ie.. the piston sizes available just so happened to exceed the oem area by a few %.

I've run huge 300z 4 pots w/ 13" cobra rotors on my maxima and yes, pedal travel is increased. But it's not a big deal as the sizes aren't that much bigger. When I had the front kit, the fronts would lock fast. Adding my custom rear kit fixed the lock and really settled the braking down. I've been there and done it already

 

The specs are the AP racing 4 piston 13 inch rotor. and the rear i believe are the same. I was seeing if the brake bias would cause my car to lock up when driving.
Thanks for the imput guys.
-Tim

 

Hmmm I don't know much about brakes either, but after reading this thread, I think the OP is wanting to get away with buying only front or only rear aftermarket brake set. So, my suggestion if this works is....Can you move your four pot fronts to the rear and replace the fronts with 6 pots?

 

no, not without totally screwing up your brake bias, unless you got custom 6 piston fronts with much larger pistons than any setup currently available. The rear will have to be custom made as well, so the cost is going to be substantial