Brake Pedal Height

[Black_Sheep]

Due to a non-stock master cylinder and 4 hole to 2 hole master cylinder adapter I am using an adjustable master cylinder pushrod. Currently it seems like my brake pedal is a little too high, making the transition from the throttle to the brake pedal kind of awkward. Can someone with a stock brake system take a measurement from the toe board to the brake pedal for comparison?

Thanks in advance…

 

[danf_fl]

On my '68 Charger, the resting brake pedal is very close to the level of the accelerator.

 

[69B7RR]

If it helps, this is the measurement off my 69RR, original manual drum master & rod….7 1/2” from floorboard (no insulation or carpet thickness) to bottom of pedal pad. If u need anything else let me know….I enjoy following your posts….jim

 

[68 Sport Satellite]

(EDIT)
keep in mind, the smaller the MC bore size, the lower the brake pedal will be towards the floor at full extension. (a 7/8" bore MC pedal travels farther than a pedal connected to a 1-1/8" bore MC)

 

[Black_Sheep]

If it helps, this is the measurement off my 69RR, original manual drum master & rod….7 1/2” from floorboard (no insulation or carpet thickness) to bottom of pedal pad. If u need anything else let me know….I enjoy following your posts….jim

View attachment 1602163

Thanks, that is exactly what I was looking for.

keep in mind, the smaller the MC bore size, the lower the brake pedal will be towards the floor at rest. (a 7/8" bore MC pedal sits lower than a pedal connected to a 1-1/8" bore MC)

The same MC has been on the car since I converted to Wilwood 4 piston calipers a year or so ago. The smaller bore provides higher pressure but requires more pedal travel, at least that’s been my experience. I don’t want the pedal awkwardly high or uncomfortably close to the floor with the brakes applied. It needs a bit of tweaking but I’ll find a happy medium now that I have a baseline…

 

[pnora]

Mine is 6 1/2 off the carpet and padding.

 

[Black_Sheep]

I adjusted the pedal from 8.5” to 7.25”, the transition from the throttle to brake is a lot better.

 

[68 Sport Satellite]

I adjusted the pedal from 8.5” to 7.25”, the transition from the throttle to brake is a lot better.

View attachment 1603066

what was your method of adjustment?

 

[Black_Sheep]

what was your method of adjustment?

This has the correct flats to properly engage the brake light switch

Right Stuff Detailing RC14 Right Stuff Detailing Brake Push Rods | Summit Racing

 

[Kern Dog]

keep in mind, the smaller the MC bore size, the lower the brake pedal will be towards the floor at rest. (a 7/8" bore MC pedal sits lower than a pedal connected to a 1-1/8" bore MC)

I don't think that is right. The pistons in the master cylinders all rest at the back of the housings.
What differs is that a larger bore master cylinder reacts in a much shorter travel distance due to the increased volume in each inch of stroke. A smaller bore unit has to travel further due to the decreased volume in each inch of stroke.
In most cases, a manual master cylinder setup does result in a pedal height off the floor a little higher than a power setup. I have 3 cars at home with manual 15/16" master cylinders and they all sit off the floor at least 1 1/2" higher than my power setup in my red car.

 

[68 Sport Satellite]

I don't think that is right. The pistons in the master cylinders all rest at the back of the housings.
What differs is that a larger bore master cylinder reacts in a much shorter travel distance due to the increased volume in each inch of stroke. A smaller bore unit has to travel further due to the decreased volume in each inch of stroke.
In most cases, a manual master cylinder setup does result in a pedal height off the floor a little higher than a power setup. I have 3 cars at home with manual 15/16" master cylinders and they all sit off the floor at least 1 1/2" higher than my power setup in my red car.

I concur. I had remembered it wrong. Smaller bore has longer travel distance so pedal at full extension is closer to the floor. Rest height is same.

 

[68 Sport Satellite]

This has the correct flats to properly engage the brake light switch

Right Stuff Detailing RC14 Right Stuff Detailing Brake Push Rods | Summit Racing

Are your brakes manual or power? I haven’t seen that adjustable rod before. In my power brake setup I do have an adjustable rod between the booster and MC bore contact.

 

[Black_Sheep]

Are your brakes manual or power? I haven’t seen that adjustable rod before. In my power brake setup I do have an adjustable rod between the booster and MC bore contact.

Manual with front disc / rear drum

 

[68-500]

First thing I noticed when I switched my Coronet to manual brakes was higher pedal at rest. All factory parts.

 

[68 Sport Satellite]

one day i might switch back to manual brakes. I used to drive a different older car with 4 wheel manual drums for 20 years and brake pedal feel and day to day stopping was excellent.

 

[Kern Dog]

one day i might switch back to manual brakes. I used to drive a different older car with 4 wheel manual drums for 20 years and brake pedal feel and day to day stopping was excellent.

That day could be now. I have everything here to make that happen. (At no additional charge)

 

[j-c-c-62]

I'm in the middle of this issue as I am typing. Had an associate install a 2 circuit 1.125" MC in a 62 Dart, that I have yet to drive. Installed a new battery to put it on the road, brake lights stuck on, killed the battery. I also noticed the brake pedal is really high (9") at rest, and my size 12 right foot gets caught easily under the brake pedal when lifting off the throttle, among other things. The Mopar adjustable push rod is adjusted all the way down. Just got yesterday a Dr Diff adjustable push rod, that is approx .8" shorter. I'm on the manual high leverage pedal setting, I can now see the light of the end of the tunnel with this issue.