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Re: Re: Big Red Stuff 2

Luis Marques <marques@rtis.ray.com> wrote:
> From: Chris Maresca <ckm@organic.com>
> > You all probably know much more about this than I do, but here's what 
> > I think about big brakes.
> > 
> > I used to have an RX7 Turbo II and it had disks that were virtually 
> > the same size as the CQ stock disks (10.8 vs 10.9), but it had four 
> > pot aluminum calipers up front.
> > 
> > I always thought those would be great on a CQ...  They're cheap,
> > plentifull, etc., the only problem would be mounting.
> And what benefit do you expect to get from them?  Unless the rotor is
> thicker or the swept area larger or it is better vented, I would venture
> to say that improvements in braking would be minimal.  You are still
> limited by the thermal mass of the rotor and whatever pad compound you
> decide to use.  Also, if the piston area is significantly different, you
> will upset the brake proportioning balance of the car.  Simply having
> trick calipers is mostly useless unless they come with better/larger
> rotors.  The exception would be if they provide significant weight
> savings or if there are better pad selections available.

So an increase in clamping force has no effect?  Assuming the 
proportioning is correctly set.

I would have thought that it would depend on what the limiting factor is.  
If the brakes can't dissipate the heat fast enough, then yes I agree.  But 
what if the caliper's clamping force/pad material/rotor material or 
surface doesn't generate enough the heat fast enough to slow down the car 
fast enough?

I thought that an increase in clamping force was also beneficial to 
braking, but in a different way than big rotors, which is also a little 
bit different than the benefits of slotting/cross-drilling.   No?

And if we're talking simply heat transfer, wouldn't a larger caliper or 
more piston surface area increase the amount of heat sink available to 
pull heat away from the rotor/pad contact area, and dissipate it into the 
air, and brake fluid?