Brake Indicator Switch and Brake System Balance

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Byron510
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Re: Brake Indicator Switch and Brake System Balance

Post by Byron510 »

Hi Keith, in your case I could see the use for this proportioning valve on the rear lines, as your brake upgrade has put more effective brakes on the rear axle. In Robyn’s case, where it will be a street driven car, the rear brakes won't work enough in combination with the larger diameter front discs. I would think that in Robyn’s case, the proportioning valve would need to be on the front brake circuit to actually balance things out, which seems a bit absurd to me...

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RMS
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Re: Brake Indicator Switch and Brake System Balance

Post by RMS »

it seems I have painted and plated myself into a conundrum. with the time and monies into the stock petals and Ebrake it does not seem cost effective for me to change out either item to a balance bar/new petals or hydraulic ebrake.

it seems I have few options:
1.sell the 280 struts and stay stock ( they have worked fine even with the tall meat on 6inches)
2. spend a bunch of cash on a rear disk setup. if one will work with the 280 fronts and allow me to run a cable e brake and 13s :lol:

3. run the rear 200 disks I have located @ 6 o'clock.(have to remove caliper to bleed, casting sits lower than the rim, gamble, have my car towed, inspection, pay

4. run the 200 disks @ 12 o'clock and find a way to get a pull on that ebrake lever. a snatch block ? maybe a bunch of linkage...mmm a big noodle (like the cantilevers on my BMX.)

or am I still faced with imbalanced brakes with the 200 calipers and will need a balance bar or proportioning valve
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bertvorgon
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Re: Brake Indicator Switch and Brake System Balance

Post by bertvorgon »

Aahh..Yes, those archaic things I remember from a time gone by, something to do with a rotating drum and some sort of silly friction type thing that may or may not actually stop a vehicle, and, in ANY direction but straight.

My Austin A40, my Chevy DELRAY, all tried to kill me under braking..... :(

And, the final end to the insanity of drums, when BERT VORGON was born, 25 minutes into a track day, when the pedal goes to the floor, I manage to get back to the pits, get out, jack car, get wheels off, crack brake bleeder, and get SCALDED by still boiling brake fluid, and I mean boiling, which says my fluid was in excess of 500+ degrees.

Anyhow, I would just pinch the front brake lines to slow down the fluid flow, then the proportioning valve MIGHT work.

Continue on......
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
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Byron510
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Re: Brake Indicator Switch and Brake System Balance

Post by Byron510 »

bertvorgon wrote: just pinch the front brake lines to slow down the fluid flow, then the proportioning valve MIGHT work.
I'll place that track advice right up with the brake marker cornering advice I one received at a track day...

"No backing off the throttle on the straits, absolute full throttle until you see god - then brake!"

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Re: Brake Indicator Switch and Brake System Balance

Post by RMS »

lets say im able to connect the ebrake on the 200 calipers @ the 12 o'clock position. will I still need to install a proportioning valve to get proper balance ?
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Re: Brake Indicator Switch and Brake System Balance

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RMS wrote: Let’s say I’m able to connect the e-brake on the 200 calipers @ the 12 o'clock position. Will I still need to install a proportioning valve to get proper balance ?
Having not run that exact set up, but set up similar cars, yes the 200SX disc will work much better than the OEM drum set up and may out power the fronts in a panic situation. In this case I would think a proportioning valve would be required.

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Re: Brake Indicator Switch and Brake System Balance

Post by RMS »

maybe I should swap the stock thing on the strut tower for a wilwood thing :
stock thing:
Image

willwood thing
Image
http://www.wilwood.com/PDF/DataSheets/ds715.pdf
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Re: Brake Indicator Switch and Brake System Balance

Post by Byron510 »

As noted earlier in this vert thread, both those items perform completely different tasks :D

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Re: Brake Indicator Switch and Brake System Balance

Post by RMS »

I realize that.... but if I understand right the stock shuttle valve thing a ma jig adds a tiny amount of balancing and is mainly to tell the driver one circuit has failed.

from wilwood: "part # bla bla bla .......portioning valve is used to adjust the rate of increase in rear brake line pressure ,relative and proportionate to the increase in front brake line pressure"

so would this not balance the system and give me the adjustments needed no matter what brakes I am running? I don't need a warning light to tell me my fluids are low that's what pre and post trip inspections are for?
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bertvorgon
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Re: Brake Indicator Switch and Brake System Balance

Post by bertvorgon »

Yes, the "thingy" on the strut tower offers no proportioning.

I cannot think of any reason why the proportioning valve would not function with the potential system you describe.
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

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1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
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Re: Brake Indicator Switch and Brake System Balance

Post by RMS »

wow only $97 in stock at mopac now the fun part can I find a 3/8 nf24 to 3/16 m10x1.0 inverted flare nut adapter
two_68_510s wrote:I guess our donkeys are quicker then your sled dogs!
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