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Master Cylinder Performance Check

- - - - - Brakes Master Cylinder Pedal Travel Heel Toe

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#1
luvin_the_rings

luvin_the_rings

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Hey Guys, 

 

I'm having trouble getting my heel-toe technique in shape in my NA.  My issue is that the pedal travel is too far, and when I'm braking, I can't get the side of my foot/heel onto the throttle to blip, its just too high.  There also seems to be about an inch of dead pedal travel before I get any braking out of the car, and what pressure I do get doesn't build up very fast, and the pedal just feels overall soft.  I bled the brakes and put new pads/rotors, it helped a bit but still unsatisfactory, and got worse after just one race.  

 

A visual check of the master cylinder shows that there is no exterior leaks or damage, so I crawled under the dash to check the pedal assy.  I found that there is about 1/16 inch of master cylinder shaft travel before I can feel any increased hydraulic resistance by hand.  I can adjust the brake light switch and thread it in further essentially pushing the pedal down a bit further to decrease the dead pedal travel.  I can also put a new pin in the pedal to MC connection as it is a bit worn.  But this doesn't fix anything, the pedal is still too far past the throttle.  

 

Is there a way to measure the MC performance to see if its shot or worn?  I've contemplated modifying the brake pedal by increasing the lever arm distance to the MC, but it seems like alot of work for something that should be working nicely in a sports car.  Are you all seeing the same 1/16" MC shaft travel before the brake pressure rises?  How firm of a pedal do you all like and how can I stiffen my brake pedal to help with Heel-toe? Could be partly my technique also, as one of my buddies says he has no trouble heel-toe'ing in the car, and his feet are even smaller than mine.  

 

Thanks, 

 

-Z



#2
Johnny D

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I don't heel-toe, I don't think Todd Lamb does either, FWIW.
Just sayin,
J~
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#3
luvin_the_rings

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I see, 

 

Pedal is still too soft though.  Need help



#4
Johnny D

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There's a lot of that going around lately. :)
J~


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#5
Jeff Wasilko

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Have you adjusted your rear brakes? That plays a big part in pedal height and feel.



#6
tburas56

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I had the exact problem with mine this passed weekend, it's the brake booster. Easy to change and it fixed the problem.

 

I do not heal and toe along with many others in these cars.


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Also tagged with one or more of these keywords: Brakes, Master Cylinder, Pedal Travel, Heel Toe

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