Freeing up those brakes...
http://www.nhra.com/dragster/1999/issue17/racing_technology.html
"Brake dancing
Here's an insider trick: Tucked inside the pages of Bowling Green Customs catalog is a Friction Reduction kit. Stock production disc-brake calipers always drag on the rotor, but with this inexpensive kit, the caliper can be compressed just enough to allow the front wheels to free wheel. It doesn't affect brake performance, but it does have an effect upon e.t. slips. To order the catalog, write to 2147 Post Oak Tritt Road, Marietta, GA 30062, or call (770) 971-4044."
http://www.bowlinggreencustoms.com/
Has anyone tried this mod?
Comments
Freeing up those brakes...
I have not, but it sounds like a good idea. Try them and let us know how they go :D
Freeing up those brakes...
I've been told that some Toyota and Hondas have small spring clips that unload the calipers. Perhaps we could adapt them to other vehicles for less $$?
Freeing up those brakes...
Some of the GM metric brakes had special master cylnders and calipers that allowed the pads to back off.
Freeing up those brakes...
[quote="katman"]Some of the GM metric brakes had special master cylnders and calipers that allowed the pads to back off.[/quote]
Kevin
Good info! Wonder if it's possible to adapt the master and calipers? or.. if we even need to? Anybody ever do anything like this?
Freeing up those brakes...
Having worked with many engineers at Bendix, here in South Bend, I know they used to design the caliper piston seals in a trapaziodal shape. The seal would pull the pistons back when pressure was removed. No need for external springs.
There is also a LOT of flex in most calipers, and warpage in rotors, IMHO all this works to keep the pistons out of contact. Keep the sliders lubed, and the pistons free. There should be little drag.
Freeing up those brakes...
[quote="fltcoils"]Having worked with many engineers at Bendix, here in South Bend, I know they used to design the caliper piston seals in a trapaziodal shape. The seal would pull the pistons back when pressure was removed. No need for external springs.
There is also a LOT of flex in most calipers, and warpage in rotors, IMHO all this works to keep the pistons out of contact. Keep the sliders lubed, and the pistons free. There should be little drag.[/quote]
My grandpa always used to complain about disc brakes when they started getting popular. Like you said, with all of the rotor warpage and caliper flexing I don't think there is much of a drag problem. It's good to see someone from my neck of the woods. What kind of car do you drive and what are you hoping to accomplish with it? We'll have to get together sometime since we live practically next door. Welcome to the site.
Freeing up those brakes...
I almost went to the Maple Syrup festival last weekend. It would be good to meet you. I am excited about groovy heads, I hope it all goes well for you next weekend.
Drum brakes have good springs to keep them from dragging. But disk brakes avoid the adjustment problem drums had. And they don't fade as badly - Federal anti fade requirements, by default, made front disk a mandatory design for cars.
Front calipers and rotors can be a problem. I ususally buy new pins and use plenty of silicon on the slider. I was surprised to learn about the trapaziodal seals but thought it a nice solution. I think there is more rolling friction in the CV joints and wheel bearings than from a properly setup caliper/rotor. IMHO
Not to mention tires. Now there's the big payoff, find a design with good traction and controlled road contact for the tire but with low rolling friction.
I should post my car faqs in the garage section I suppose.
Freeing up those brakes...
[quote]Front calipers and rotors can be a problem. I ususally buy new pins and use plenty of silicon on the slider. I was surprised to learn about the trapaziodal seals but thought it a nice solution. I think there is more rolling friction in the CV joints and wheel bearings than from a properly setup caliper/rotor. IMHO[/quote]
When I first got my Saturn, I had the opposite problem. The brakes just didn't seem very good and there was a bit of a shudder while stopping. I took it to Mufflers Unlimited and had it checked out and they found that one of the oins was frozen solid which meant that side wasn't working at all. The rotor on the other side was shot. After replacing all the bad stuff everything has been fine ever since.
[quote]I almost went to the Maple Syrup festival last weekend. It would be good to meet you. I am excited about groovy heads, I hope it all goes well for you next weekend.[/quote]
You should have come over to the syrup festival. I had the all you can eat pancakes and sausage Friday night. I could have used some help. I thought it was eat it all so I ended up having 4 pieces of sausage and about 13 pancakes. :smt100 :smt119
Freeing up those brakes...
I ended up at Honkers sat, while my car wheels were replaced at discount tire. They did a good job, for $90 got all 4 changed and balanced, wheels checked for warps, and new stems. A lot of work getting those 5" hub chrome wheel covers unbolted and moved to the new wheels.
The steel wheels had corroded, but I found newish ones at the Gertrude street recycling center. Mr. Soezoh has a line of Daytonas there he's hoping to rebuild. The Daytona with the crushed rear end, #059, had just the right wheels. It was a 6, otherwise I might have gotten a 782 head as well.
I entered a bio/car fact in the intro forum today.
Freeing up those brakes...
[quote="fltcoils"] Drum brakes have good springs to keep them from dragging. But disk brakes avoid the adjustment problem drums had. [/quote]
Years ago I remember modifying drum brakes so they wouldnt self center or self adjust to reduce drag....of course back then I was more interested in performance than mileage (The old 289 'only' got about 27 mpg round town)