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Brake boost issues.

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Old Oct 6, 2025 | 04:49 PM
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Default Brake boost issues.

Has anyone swapped their brake booster for a new metal Cardone 5C-471401? I got one for the 84' and it fit fine however I noticed the brake pedal was sitting lower than the clutch and the brake pedal is a good 1/2" or more away from the switch buttons. Seems like the booster rod is too short. I dont have the old boost to compare. Anyone run into this issue?
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Old Oct 13, 2025 | 10:44 AM
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Anyone have a factory booster laying around and can measure the pedal rod length for me? I sent Cardone a message about my issue awaiting a response I should not have to cut on a brand new booster to fix a issue that should not be there.
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Old Oct 13, 2025 | 10:52 AM
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I believe that is the booster I purchased.
I will start with boosters are not plug and play, there is an adjustable rod between booster and master. That needs to be setup correctly.
Secondly, the brake pedal is lower than clutch pedal on my 86.
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Old Oct 13, 2025 | 11:12 AM
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I know how boosters work I have changed dozens over the years. That said was your pedal lower than the clutch with the old factory booster? I'm not modifying other parts to make a part that should fit work. Plenty of guys replace boosters and I barely heard any talk about the pedal rod being short and switches not touching. I know my pedals did line up when I got the car to bad I tossed the old booster before I noticed a issue!
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Old Oct 13, 2025 | 11:18 AM
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Yes, my brake pedal was and is lower than clutch pedal. About 1 1/2”
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Old Oct 13, 2025 | 11:46 AM
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So do all the c4's have different pedal heights? I tried to research this also and could not fine a definitive answer.
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Old Oct 13, 2025 | 05:03 PM
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Well I pulled the brake booster back off today and measured the pedal ride and it is 6 3/4" from the mount face to eyelet center. If anyone has a booster off the car could you grab a measurement for me so I can compare. I will say I have no idea what was done to this car over the years I just got it so I'm keeping that in mind as well.
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Old Oct 14, 2025 | 07:55 PM
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I just replaced the booster on my 87. The rod is 7-1/8 overall and 6-3/4 to center of the hole. Mine is an automatic
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Old Oct 15, 2025 | 08:51 AM
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Was that the new one you measured or both new and old?
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Old Oct 15, 2025 | 09:40 PM
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The old one. The new one is installed already. I have no.difference In pedal height
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