Re: Race car brakes, where did I go wrong?
[Re: The Sphinx]
#2515970
07/01/18 06:05 PM
07/01/18 06:05 PM
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Joined: Jan 2003
Posts: 14,492
So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,492
So. Burlington, Vt.
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Get yourself a gauge and start checking pressures.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
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Re: Race car brakes, where did I go wrong?
[Re: fast68plymouth]
#2515977
07/01/18 06:18 PM
07/01/18 06:18 PM
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Joined: Sep 2014
Posts: 4,457
Washington
madscientist
master
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master
Joined: Sep 2014
Posts: 4,457
Washington
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Get yourself a gauge and start checking pressures. This^^^^^^^^^^^^ Until you know how much line pressure you have you are just guessing. My WAG is you cobbled a bunch of crap together and you can't generate enough line pressure to make it stop.
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
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Re: Race car brakes, where did I go wrong?
[Re: The Sphinx]
#2515979
07/01/18 06:20 PM
07/01/18 06:20 PM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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some random thoughts, you might get it up on stands & see if you can bearhug & turn each whell forward while a helper holds the pedal. You get some parts house 3/16 inverted flare fittings/short prefabbed 3/16 brake line & bypass the prop valve. You can cap the MC ports & the pedal should be rock hard with virtually no travel (try easy pedal & try stomping on it) then hookup the fronts & see if the front wheels are bearhug tight. Holler how it goes
live every 24 hour block of time like it's your last day on earth
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Re: Race car brakes, where did I go wrong?
[Re: The Sphinx]
#2515995
07/01/18 07:01 PM
07/01/18 07:01 PM
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Joined: Jan 2003
Posts: 8,021
Tulsa OK
Bad340fish
master
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master
Joined: Jan 2003
Posts: 8,021
Tulsa OK
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If you have access to a pressure bleeder you might give that a try. I just changed masters and added rear discs and I was unable to get the rears to work until my dad brought over his pressure bleeder. I could get fluid at the rear but no pressure and no pedal. A few minutes with the pressure bleeder and all was well. There was lots of air in the rear lines even though what little fluid i was getting appeared fine.
68 Barracuda Formula S 340
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Re: Race car brakes, where did I go wrong?
[Re: The Sphinx]
#2516012
07/01/18 07:43 PM
07/01/18 07:43 PM
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Joined: Dec 2005
Posts: 11,526
Fulton County, PA
CMcAllister
Mr. Helpful
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Mr. Helpful
Joined: Dec 2005
Posts: 11,526
Fulton County, PA
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To even have a chance of figuring anything out, you need to know bore sizes of the MC and calipers.
If the results don't match the theory, change the theory.
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Re: Race car brakes, where did I go wrong?
[Re: The Sphinx]
#2516034
07/01/18 08:14 PM
07/01/18 08:14 PM
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Joined: Jan 2005
Posts: 2,540
Milwaukee WI
TRENDZ
master
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master
Joined: Jan 2005
Posts: 2,540
Milwaukee WI
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Im not familiar with the speedway brackets. Are they bolt on or weld on? I had a guy bring a car to me with the same symptoms. He bought and installed weld on brackets on the rear axle. They were not square to the rotors. All I did was cut them off, had the boy apply the brakes, and welded them on correctly. No bleeding, great pedal.
Before doing any of this, I had the wheels off with the rotors bolted in place. Watched each wheel as he applied the brakes. You could see the calipers on both rears move at angles.
"use it 'till it breaks, replace as needed"
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Re: Race car brakes, where did I go wrong?
[Re: TRENDZ]
#2516044
07/01/18 08:35 PM
07/01/18 08:35 PM
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Joined: Dec 2004
Posts: 10,552
Rittman Ohio
fourgearsavoy
I Live Here
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I Live Here
Joined: Dec 2004
Posts: 10,552
Rittman Ohio
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Im not familiar with the speedway brackets. Are they bolt on or weld on? I had a guy bring a car to me with the same symptoms. He bought and installed weld on brackets on the rear axle. They were not square to the rotors. All I did was cut them off, had the boy apply the brakes, and welded them on correctly. No bleeding, great pedal.
Before doing any of this, I had the wheels off with the rotors bolted in place. Watched each wheel as he applied the brakes. You could see the calipers on both rears move at angles.  I have seen people weld these brackets on without positioning the caliper with air before they tack it on. Gus 
64 Plymouth Savoy
493 Indy EZ's by Nick at Compu-Flow
5-Speed Richmond faceplate Liberty box
Dana 60
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Re: Race car brakes, where did I go wrong?
[Re: Bad340fish]
#2516058
07/01/18 09:19 PM
07/01/18 09:19 PM
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Joined: Jan 2004
Posts: 8,233
fredericksburg,va
cudaman1969
master
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master
Joined: Jan 2004
Posts: 8,233
fredericksburg,va
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If you have access to a pressure bleeder you might give that a try. I just changed masters and added rear discs and I was unable to get the rears to work until my dad brought over his pressure bleeder. I could get fluid at the rear but no pressure and no pedal. A few minutes with the pressure bleeder and all was well. There was lots of air in the rear lines even though what little fluid i was getting appeared fine. I go along with this answer, mushy means air.
Last edited by cudaman1969; 07/01/18 09:19 PM.
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Re: Race car brakes, where did I go wrong?
[Re: The Sphinx]
#2516196
07/02/18 01:04 AM
07/02/18 01:04 AM
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Joined: Mar 2009
Posts: 2,458
Sydney,Australia
tex013
top fuel
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top fuel
Joined: Mar 2009
Posts: 2,458
Sydney,Australia
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too small a master cylinder bore will give a soft low pedal .But will pull up fine as long as its not on the floor .
I think Mark Williams has a calculator to work this out
Tex
New best ET 10.259@129.65 .
New best MPH 130.32
Finally fitted a solid cam,
stepped it up a bit more
3690lbs through the mufflers
New World block 3780lbs 10.278@130.80 . Wowser 10.253@130.24 footbraking from 1500rpm
Power by Tex's Automotive
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