1" bore master cylinder ?

[calrobb2000]

hi

is there a 1" bore aluminum master cylinder to use with non power disc / drum brakes ?

thank you !

 

[GTX JOHN]

15/16 is closest I know of and what we run.

 

[72bluNblu]

Wilwood makes a 1” bore aluminum master cylinder that I’ve see used. I like the 15/16” from DoctorDiff myself, I use it on all my manual disk mopars. Great line pressure, manageable pedal effort and a good travel range for brake modulation and control.

 

[RustyRatRod]

It's been my understanding that the smaller bore gives more pressure and stopping power using manual brakes. Is that incorrect?

 

[motorpirate]

It's been my understanding that the smaller bore gives more pressure and stopping power using manual brakes. Is that incorrect?

Yea, thats right, higher pressure with a little longer travel.

 

[roccodart440]

Wilwood makes a 1” bore aluminum master cylinder that I’ve see used. I like the 15/16” from DoctorDiff myself, I use it on all my manual disk mopars. Great line pressure, manageable pedal effort and a good travel range for brake modulation and control.

x2, but I personally use the 7/8 master. "Poor man's power brakes"

 

[Jarlaxle]

I THINK that the stock 80-82-ish D/B100 master cylinder is a 1.125" bore.

 

[72bluNblu]

It's been my understanding that the smaller bore gives more pressure and stopping power using manual brakes. Is that incorrect?

Yea, thats right, higher pressure with a little longer travel.

Exactly so! Smaller master cylinder bore will generate higher brake line pressure, but will result in longer pedal travel. So there is a limit to how small you go, you want to have some extra room before the pedal hits the floor since you'll need more travel when things start to get hot

x2, but I personally use the 7/8 master. "Poor man's power brakes"

Yup, that would be an even higher line pressure than the 15/16", with slightly more pedal travel. I haven't used one on an A-body but I'm sure that still leaves plenty of pedal travel in reserve.

I THINK that the stock 80-82-ish D/B100 master cylinder is a 1.125" bore.

Sounds right, I think the Diplomats/5th aves used a 1-1/32" in a similar package. DoctorDiff sells those as 1-1/32", or sleeved down to 15/16" (which is what I use).

1-1/8" would be a pretty "high and hard" pedal though. Factory sizes for these cars were 15/16", 1" and 1-1/32" depending on the year and brake set up.

 

[Jarlaxle]

Exactly so! Smaller master cylinder bore will generate higher brake line pressure, but will result in longer pedal travel. So there is a limit to how small you go, you want to have some extra room before the pedal hits the floor since you'll need more travel when things start to get hot

Yup, that would be an even higher line pressure than the 15/16", with slightly more pedal travel. I haven't used one on an A-body but I'm sure that still leaves plenty of pedal travel in reserve.

Sounds right, I think the Diplomats/5th aves used a 1-1/32" in a similar package. DoctorDiff sells those as 1-1/32", or sleeved down to 15/16" (which is what I use).

1-1/8" would be a pretty "high and hard" pedal though. Factory sizes for these cars were 15/16", 1" and 1-1/32" depending on the year and brake set up.

I know-Rick Ehrenberg LIKES the rock-hard pedal.

 

[72bluNblu]

I know-Rick Ehrenberg LIKES the rock-hard pedal.

Apparently!

I know in one of the earlier Green Brick articles he said they used a 1-1/8” in the brick, although one of the later articles said 1-1/32”.

To each their own, I like the 15/16” way better.

 

[Bewy]

Getting down to 7/8" m/c bore, you would want to check that there is enough fluid volume for disc brakes.

 

[RustyRatRod]

x2, but I personally use the 7/8 master. "Poor man's power brakes"

Who has one with the four bolt flange and correct size flare ports for the Mopar? Gotta part number?

 

[Jarlaxle]

Getting down to 7/8" m/c bore, you would want to check that there is enough fluid volume for disc brakes.

That's a big reason E-berg likes the larger bore-it mitigates pedal sink from heat, and makes "running out" of pedal less likely. (Bearing in mind: the car in question is a 550+hp road racer.)

Who has one with the four bolt flange and correct size flare ports for the Mopar? Gotta part number?

Might be easier to use the MP or AR adapter for the 2-bolt MC.

 

[roccodart440]

Who has one with the four bolt flange and correct size flare ports for the Mopar? Gotta part number?

I believe mine is a 2 bolt and I used a 2 bolt master cylinder offset bracket.

I used a wilwood 7/8 master I bought from RMS is the best I can tell you.

 

[qkcuda]

I bought a 2 bolt aluminum master listed for a manual brake 1980 Volare or Aspen and it is 1 1/32 bore. I haven't tried it yet to be able to report on pedal pressure.

 

[Jarlaxle]

I bought a 2 bolt aluminum master listed for a manual brake 1980 Volare or Aspen and it is 1 1/32 bore. I haven't tried it yet to be able to report on pedal pressure.

got a PN?

 

[qkcuda]

I'll check at home.

 

[inertia]

I also use 7/8 M/C on my racecar builds, not much fluid volume needed to push 10 caliper pucks a coupla thou. lap after lap !
I use 15/16 on my A-bodies .

 

[qkcuda]

Here is a picture of the box. It is a Dorman M99294.