Bendix Power brake booster push rod length

[MrDee]

That mc uses an e ring to positively locate the plunger. My mc just uses that retaining bolt on the bottom so the plunger doesn't fall out, lol. Thanks for the photo.

 

[MrDee]

Not a problem, I've actually finally figured it out. I found this old Master Tech video on the operation of our Master Cylinders.
Chrysler Master Tech - 1970
Volume 70-9 Brake Hydraulics
The operation is basic of course, but, the video shows a couple photos of the primary and secondary pistons when at rest. The rubber pressure cups are positioned just behind the compensating ports, and the filler ports are halfway open. These facts means the master cylinder piston must be even/flush with the mc mounting surface, not protruding out 160 thousandth like it does in an unmounted- at rest position. By setting the booster rod length to .910, the mc piston is flush with the mc mounting surface when it's mounted.

And just a follow up, my brake system is finished and brakes work amazing. Perfect pedal feel using the .910 rod length. I would have had a mess and been doing it all over again had I believed the .020 gap method. That does NOT work on early Mopars!

 

[RemCharger]

And just a follow up, my brake system is finished and brakes work amazing. Perfect pedal feel using the .910 rod length. I would have had a mess and been doing it all over again had I believed the .020 gap method. That does NOT work on early Mopars!

Good detective work. On the 66 models they call for .933- .943 on the bendix booster. Interestingly enough, there is no form of piston retention. Of course that was a single pot though

 

[MrDee]

Good detective work. On the 66 models they call for .933- .943 on the bendix booster. Interestingly enough, there is no form of piston retention. Of course that was a single pot though

All the online research I did said to put .020 between the boost push rod and master cylinder plunger. That's 100% wrong for my 69 GTX. I just thought people should hear the truth, there's too much wrong info out there.