Hard Core Brakes

[XXAIX]

This information is for hard core late braking RACERS. In past conversations regarding brake systems, in particular rotor size there has been much discussion about “bigger is not always betterâ€

[spdracer22]

This seems interesting...

 

But...the only additional information I've found is from here: http://larsenracing.zoovy.com/product/DPI_2150

 

Could you post some pictures of your install? Do you know the website for the manufacturer?

[white_2kgt]

We used the optional front and rear master cylinder equalizer which was nothing more than a brake line tube connecting the front and rear master cylinders. This simple little modification eliminated the need for a bias bar or proportioning valve. It stopped rear brake lockup by bleeding the rear system pressure to the front system as the brake pedal is depressed.

 

Why is it better than a dual MC balance bar? Do you use something like a prop valve to adjust the bias F/R? Can you get 60/40 F/R brake application with it or is is 50/40 like a prop valve would be?

 

Pictures of this system would be outstanding. Is the return line for the rec system pressurized the same as the feed lines or is it under MUCH less pressure?

[FBody383]

http://www.dpiracingproducts.com/surestp_techtip.htm

 

Thanks for finally dropping their name so I could find it; all the circle track guys probably knew where to look.

[XXAIX]

As far as I know all a proportioning valve does is control the flow of brake fluid to the front and rear calipers. It mostly slows/impedes the flow of brake fluid to the rear caliper relative to the front. Left to their own devices the rear system will always pressurize before the front. The object is to get the front and rear systems to apply clamping force on the rotors simultaneously. By tying the front and rear mater cylinders together by use of a simple tube and bleeding the rear system pressure to the front system it seemed to have done this perfectly. Balance bars have a tendency to bind in some conditions and the equalizer tube is a static VS dynamic device. Oh yeah, and its much lighter.

 

Sorry guys I don’t have pictures but it is a simple straight forward install and the DPI system has an adequate instruction sheet.

 

We didn’t have a pressure gauge on the return lines but as it is a closed loop system I would assume the pressure would be equal on the return lines.

 

One thing we did different was to drill internal ports in the calipers to eliminate the external tube assemblies.

[white_2kgt]

By tying the front and rear mater cylinders together by use of a simple tube and bleeding the rear system pressure to the front system it seemed to have done this perfectly.

 

So basically there is NO user adjustment you can make in-car like w/ a balance bar? You are just relying on the pressures to equalize themselves out? What if you need less rear brake mid race?

[davidfarmer]

I don't know the purpose of this thread. Circulating systems have been available for a long time, but I'd personally rather have a properly sized and cooled system, than rely on even more plumbing. Plus, when you do bleed, you have to bleed the entire system.

 

Anyway, I certainly don't understand the front/rear biasing description. Normal adjuster (knob and lever) are crap, as they are just spring loaded cylinder that let the lines expand a bit. Basically, you still get too much pressure until you reach a certain point, then the "give".

 

Connecting the two systems (front/rear) only makes since if the master cylinders and caliper pistons are absolutely perfectly matched. Even then, you wouldn't need to connect them. Plus, the only way to match systems is by trial and error, and nothing beats dual masters with a balance bar.

 

Anyway, thanks for the advertisement.

[XXAIX]

white_2kgt

 

You will not need less rear brakes if your front brakes work consistently throughout the race.

 

David

 

Circulation systems have been around for a long time but until we ran one on the TCP #34 AIX Mustang I never saw one on a road race car, although I’m sure someone probably has. There may be properly sized brake systems but there is no such thing as a properly cooled system under all racing conditions with just ducting. Have you ever raced a street circuit? I have. There was enough added cooling ducting to operate a church pipe organ on most of the cars and there were still a LARGE number of the 34 cars that literally had their proper factory ducting catch fire due to the overheated properly sized Swift, Lola and Tiga brake systems. There was a car that burned to the ground because of it.

 

Yeah, I’d much rather have no brakes than a couple of extra lines. We ran the system for a year with zero problems and while everyone else was constantly bleeding their systems we just inspected the pads and rotors.

 

What part of self-bleeding did you not understand?

 

David, have you ever used a circulation system? It certainly doesn’t sound like it. Front and rear systems will never be perfectly matched. That is the reason for proportioning valves, balance bars or circulation systems. “Even then you wouldn’t need to connect themâ€