35 replies to this topic

[3GCVC]

My general rules for upgrading brakes on "street driven" cars is to; upgrade the master cylinder to the size that was originally used by Honda for the car that used the front calipers. which in this case is 15/16inch.

Sometimes the booster requires upgrading due to the size of the master cylinder upgrade so I will use the smallest booster possible to help pedal feel.

 

I have used this method for a long time and have upgraded countless brake systems in this way, pedal feel is always good in the cars I have upgraded, plenty of stopping power no problems with rear brake bias so long as the correct proportioning valve is used for the rear brake type.

 

 

Scott I would suggest you at least upgrade to the 7/8inch 1985 Prelude master cylinder which is just one size down from the 15/16inch master and its a bolt in swap to the stock booster.

 

To wade into the debate about aftermarket multi-piston calipers IMO the biggest gain is caliper rigidity and reduction of unsprung weight, all alloy calipers and multi piece rotors are very light, one recent upgrade I am working on upgrading from stock 282x21mm brakes to 300x28mm adds almost 10kg per side of unsprung weight.

[cbstdscott]

My current set up is Integra rotors and calipers in front, aluminum drums in rear, stock MC and Portioning valve, no brake booster. This combination works well for my uses.

 

My first step will be to install the new calipers (the 200 Mustang Cobra bits work perfectly for the rebuild). Once I get a base line on how the calipers work with the rest of my brake system I will move forward with changes to the MC and restoring the brake booster if needed.

 

But... I have a car show this coming Saturday so I will not start the process until that is done.

[Site]

You guys are looking at this from the wrong angle.  The advantage of multiple piston calipers has nothing to do with clamping force.  The advantage of multiple calipers is that the clamping force is more evenly distributed over the back of the brake pad, enabling the use of larger pads over what you could use with a single piston.  This, arguably, is the better way to go to increase brake performance as a larger friction surface means a larger area of contact with the brake rotor.  Since the kinetic energy removed by stopping your X lb car from Y mph in Z feet never changes, a bigger contact surface means less generated heat per unit of surface area and better heat dissipation, resulting in less brake fade.   One thing I am certain of is that piston size and number is not a terribly important factor in stopping distance if you already have enough braking power to lock the front wheels.  In short, it is doubtful that you would see much difference between single piston and multiple piston brakes on the same vehicle with the first heavy stop.  But after multiple heavy stops?  The difference would be dramatic.  That's the main advantage of the Integra brakes on my CRX - multiple and repeated braking events over the course of a 25 minute club race (the car is a former ITB Regional Champion), but for what I do, autocross, I'd be willing to bet I would not see a difference in switching back to the stock brakes.

 

Drag racers used to love drum brakes over disc brakes.  Why?  Less fade, because of the larger surface area of the shoes, the larger mass of the drum, and  the subsequent generation of less heat because of the larger contact area, the greater ability of the larger components to absorb that heat, and the greater dissipation of that heat.

 

my view has always been that the reason drag racers prefer drums is because they are more effective, and better for one single duration of braking...they do not dissipate heat as good as you make them out to (they distribute the heat better, as they have a larger thermal mass)...but drum brakes are awful for repetitive track use and repetitive braking, this is mainly due to not getting sufficient air flow etc to remove heat...i totally agree for one duration of braking they are great as you've said, mainly as they have a much larger surface area of brake shoe etc, and yes they have a larger mass to absorb the heat...but once they have heat inside them good luck getting rid of it!

[cbstdscott]

Disc brakes "drag" just a bit while drum brakes can be adjusted to a have no contact at all. 

[cahitapower]

this right here!... 143.62005   < time saver!

 

thanks alot scott !!...

[Andy69]

 

my view has always been that the reason drag racers prefer drums is because they are more effective, and better for one single duration of braking...they do not dissipate heat as good as you make them out to (they distribute the heat better, as they have a larger thermal mass)...but drum brakes are awful for repetitive track use and repetitive braking, this is mainly due to not getting sufficient air flow etc to remove heat...i totally agree for one duration of braking they are great as you've said, mainly as they have a much larger surface area of brake shoe etc, and yes they have a larger mass to absorb the heat...but once they have heat inside them good luck getting rid of it!

 

Yes and no.  Heat dissipation is a bigger problem for drum brakes, which is why disc brakes won out.  However, with proper setup, you can get some very good results with drum brakes, including on road courses and not just drag racing.  The main problem with drum brakes is heat buildup inside the drum, which can reak havoc with brake lines and brake fluid.  But, by employing various tricks one can increase this heat dissipation.  Drilling vent holes in the bakcing plate, using newer shoes with better materials, higher boiling point brake fluid, aluminum drums with cooling fins (my GS400 had these on the front when I got it - they dissipate heat a lot better than standard cast iron drums),  But, in the end, disc brakes are just better all around.