Dustu
Active Member
What disc. brake conversion for a 71' Cuda is a good choice for non power and good not hard pedal feel ? Same as factory quality ,street setup . We wanted power disc but not enough vacuum, no vac. pump. no chevy calipers .
On your e body conversion did you have power drums already ? So you used the combo factory valve, was it for a non power disc.. car ? I see with metering valve ,have the part no s.? I have read that it was recommended to use a smaller dia. master cylinder ,7/8 ,15/16 maybe ? But yours sounds good . Did you have to do anything with the pedal to master cyl. ratio ?I used all factory Mopar parts following the Disc-O-Tech article with a few exceptions for manual brakes. I used the combination valve used after 1-1-1970 with the metering valve. Rotors are 11.75” (need 15” wheels), Dr. Diff’s aluminum 1.031 master (not excessive pedal force), semi metallic pads. My car feels like my Acura RDX pedal does. Car stops great, no rear wheel lockup. I found that out in an unexpected panic stop on the Interstate with rapidly slowly traffic. That stop definitely built up my confidence in the car’s abilities to stop around modern stuff. I also had experimented with and without the metering valve. Too much nose dive without it. With the metering valve very little nose dive and more weight on the rear as I my unplanned panic stop proved to me.
I found all Mopar sourced parts work well together. There are a lot of available brake kit options.
The master cylinder bore size is the wildcard, it’s a subjective feel. After increasing my master cylinder to 1.031, I was surprised that the pedal feel was virtually the same with half the travel, slightly more pressure. Extremely happy with my setup and stopping power.
not doing powerI have done many of the 11.75 Cordoba disc swaps , hydroboost is a better option with low vacuum if you want power & have power steering which my cars do not .
My car was manual. Since the factory didn’t offer a manual disc brake car in ‘70, I used the factory system because it was engineered for disc brakes. Also stuck with all Mopar sourced parts because I lean towards the factory parts which work well together. The brake pedal is the same for all cars, except the power brake cars used the linkage assembly. My stock brake pedal is a hair over 7:1.On your e body conversion did you have power drums already ? So you used the combo factory valve, was it for a non power disc.. car ? I see with metering valve ,have the part no s.? I have read that it was recommended to use a smaller dia. master cylinder ,7/8 ,15/16 maybe ? But yours sounds good . Did you have to do anything with the pedal to master cyl. ratio ?
... I used the factory system because it was engineered for disc brakes. Also stuck with all Mopar sourced parts because I lean towards the factory parts which work well together. ...
Do you remember what M C was for exactly ? Or did you just use the power disc. m c for 70 ' ebody and a 70 e body model combo and metering valve ? Correct ?My car was manual. Since the factory didn’t offer a manual disc brake car in ‘70, I used the factory system because it was engineered for disc brakes. Also stuck with all Mopar sourced parts because I lean towards the factory parts which work well together. The brake pedal is the same for all cars, except the power brake cars used the linkage assembly. My stock brake pedal is a hair over 7:1.
The master cylinder bore size is the wildcard. I went with 1.031 MC because the pedal travel with the 15/16 MC was uncomfortably long for my comfort level. Also with a psi gage on the front caliper, I had to put a lot of leg on the pedal, was nearly touching the floor and was still just under 1200 psi. Not a confidence builder for me. So I changed to 1.031 and never looked back. It came down to my comfort level and the ability to comfortably stop the car in all situations. That’s the MC that worked for me, not excessive pedal force, and the car stops quite well. My Acura RDX also has some variable pedal force component depending on the conditions required to stop the car at any given moment. That was my overall goal. It is a total package considering the entire braking system, including the friction coefficient of the brake pads.
Upside is the MC is easy to change and I have a pressure bleeder and tool C-4121 to hold the metering valve open. I’ve changed many MCs, some because they where Chinese junk and leaked, others searching for my comfort zone. So changing them was only a slight inconvenience.
I used this combination valve. The MC was from Dr. Diff. It was the aluminum 1.031 MC. It had the Mopar 1/2-20 and 9/16-20 ports. The pic was from Dr Diff’s website. He has both the combination valves and the MC. He is a great guy to deal with. He also has the 15/16” MC in the aluminum style. Both MCs have the recessed groove to retain the manual brake pushrod.Do you remember what M C was for exactly ? Or did you just use the power disc. m c for 70 ' ebody and a 70 e body model combo and metering valve ? Correct ?