IndianaOpenWheel.com Sprint Car & Midget Racing Forum





Register! Forgot Password?
Post Reply
torkman15 (Offline)
  #1 7/9/14 9:11 PM
I'm racing my heat race and have about a half lap lead on the pack and with 2 laps to go someone blows a motor and put a mile wide smoke screen up. I just lightly got on the brakes and everything seems right but on the restart my car would not accelerate like my brakes are dragging, everyone passed me and I dropped a gear and still bogging made the last lap and pulled in. My brake rotor was glowing and very hot so I cracked loose the brake line at the caliper and fluid came out boiling and then the caliper let go of the rotor. I took the 2 pound residual valve apart and left the guts in the trailer, fought for a half hour or so to bleed the brake but got it done. The question is do I really need the residual valve??? I don't think the caliper is very much higher than the master cylinder at normal ride height. I never use my brakes at any time but panic stops on track (very rare) and some in the pits.

Thanks, Tom
suzuki756 (Offline)
  #2 7/9/14 10:17 PM
Never
torkman15 (Offline)
  #3 7/10/14 4:22 PM
Never what?
Likes: AustinSprinter
AustinSprinter (Offline)
  #4 7/10/14 4:33 PM
hold on!!...TQ29m is looking!!....
____________
Brucer'
Likes: TQ29m
team flying pig (Offline)
  #5 7/10/14 4:42 PM
Anytime the master cylinder is mounted below the horizontal plane of the calipers, a residual valve is necessary. You can verify this on wilwoods website.
TQ29m (Online)
  #6 7/10/14 6:42 PM
Originally Posted by AustinSprinter:
hold on TQ29m is looking!!....
____________
Brucer'
Brucer, I wasn't but I am now! And you have set me to searching. I never have run one, and my first thought would have been, why would I need one, so I did a brief run down on Google, and the way I understand what is written, it is a valve, 2# for disc brakes, and 10# for drum brakes, to keep the fluid from backing up the brake fluid lines, and assure a normal, rather than soft peddle on the first jump on the brakes, it went on to talk about master cyl and caliper positions, but also reservoir location, seems the thought is if the reservoir is above the highest caliper, none is needed, my calipers are all within the gudelines, and my reservoir is at least 12" or so, above the highest caliper, so I have gravity working in my favor, thus I have not had any trouble with brakes, as long as they don't fall off! I usually run at least a 1" master cyl, as it doesn't override the caliper, and gives better peddle feel, and by being that large, when you get off the brakes, it helps pull the pads off the rotors. IMHO, the problem this driver had, was his master cyl was too small, and overrode the caliper, kinda one of them overcenter deals. In my opinion, he doesn't need one, but needs to look at the master cylinder. Thanks for the wake up call. Have a good day! Bob

"Being old, isn't half as much fun, as getting there"! Ole Robert I!
Likes: AustinSprinter
torkman15 (Offline)
  #7 7/10/14 7:47 PM
Ok things are starting to make sense now. The car had a front brake on it when I bought it but I never used it (it had a shutoff valve) I decided to remove the front disk, caliper and lines to save weight. It was not long after and I had troubles...
AustinSprinter (Offline)
  #8 7/11/14 2:48 AM
Bob!!..always enjoy reading your great comments to Tech problem questions!!......
________
Brucer'
Likes: TQ29m
Post Reply