2229171 Master Cylinder Lid Differences

[mtull]

Regarding 9171's most of my reading has been focused on casting and assembly dates but have not put much time into educating myself on the characters stamped into the lids.  I thought I'd read on our forum that up until mid-year production the lids would have: "USE ONLY SAE 70 R3 BRAKE FLUID".  The later production cars would have: "USE ONLY SAE J1703 BRAKE FLUID" and at some point the following year the lids had no stamping.

After re-reading 171-master-cylinder I'm second guessing my memory with regards to different stampings on early/later E-Body cars.

Can anyone confirm please?  Also, can anyone tell me if the lids (production line or afterwards) were ever plated prior to paint?

Thank you

[JH27N0B]

The lid on the left is a B body disc brake cap.  I've never seen that callout on the lids on Mopar cylinders for E bodies.  The disc B Body master cylinders from 1967 through 70 were narrower and taller castings than the 9171/9191 and the caps aren't interchangeable with E body masters.
The chemist at my old work showed me a document on when the SAE standard was changed to a new one J1703 and it was actually much earlier than the 1970 model year, might have been 1968 or even 1967. I should have made a copy of that standard to keep when I worked there, but sadly I did not. It probably took a while for the change to work through the system and the change to be reflected in what they stamped in MC caps.
This SAE listing seems to indicate it was first issued in 1967:
https://www.sae.org/standards/content/j1703_201909/
I highly doubt any 9171 or 9191 caps would have been stamped anything but J1703 in the production years of 1969 through 71.
Resto Rick offered a service to stamp the J1703 callout in unstamped caps, I assume he still does but one would need to ask him.

[Floyd]

Rick is still doing them.  He stamped a lid for me a few months ago.

[mtull]

@JH27N0B  "I highly doubt any 9171 or 9191 caps would have been stamped anything but J1703 in the production years of 1969 through 71"
Thank you for your expertise.  I'm inclined to go with your assertion above.

I recall another thread where someone pointed out to @Floyd the differences between the E & B MC lids but couldn't find the thread.  Thank you for confirming.

Not to throw a wrench in the works but I just noticed the two E-Body convertible Pilot cars built on Aug 1, 1969 have B body disc brake caps?
Would that be another anomaly or perhaps a deviation during restoration or?

https://www.mecum.com/lots/499121/ 
https://www.mecum.com/lots/499120/

Thanks again for sharing your wealth of knowledge.

[mtull]

Doh!  I just noticed the MC on the 70 Challenger pilot car is not a 9171. 

[JH27N0B]

Neither of those is a 9171.  The one on the right isn't even a Bendix master cylinder, it has a fixturing machined recess in the "nose" of the front of the casting.  Aftermarket master cylinders seem to always have those, but apparently Bendix had a different way of retaining the casting in the tooling when they were machining them, as they don't have that machined recess in the nose.
Looking at a picture of a restored car is a sketchy way to research what is OE correct. It can create sort of a "garbage in, garbage out" situation as someone does something wrong on their build, others see that and use as a reference, and perpetuate the mistake. One common example is people using pictures of undersides of cars to use to copy the manufacturing line paint markings on their restoration.  Each car was a little different, so unless you can document the original markings on your car before restoring it, you are sort of SOL ever being able to know what the paint and chalk marks on it were.
Pictures from vintage magazine articles when you can find one that shows under the hood is much better reference, but maybe still not perfect.  I have a magazine stashed somewhere that has a road test of the then new for 1970 hemi cuda, and the master cylinder on it looks too big.  There was a master cylinder used on disc brake 67-69 C bodies that looked like a 9191 but was about 10% larger.  I'm pretty sure that was what was on that hemi cuda.  How did it get there?  We will never know.  But I would guess the car was a pilot car that made the rounds being loaned to various magazine writers to test, and the brake master cylinder went bad, and it was replaced with something close at a dealer as the 9191s weren't yet in the Chrysler parts distribution network, so they used that rather than have the cuda out of service for a week or two until one could be found and shipped from the factory? Or maybe even installed at the plant for a pilot build if the 9191s hadn't yet been supplied?
Here is a picture of the C body master cylinder that is very similar but larger than a 9191.
https://www.hiltopautoparts.com/product/nos-mopar-master-cylinder-1966-9-c-body-with-power-disc-brakes/

[mtull]

JH27N0B,

Thank you.  "Looking at a picture of a restored car is a sketchy"  Lesson learned.

[6bblgt]

https://forum.e-bodies.org/parts-misc-for-sale/9/1970-lid-only-disc-brake-master-cylinder/29220/msg320216#msg320216

pics of E VS B-body lids - inside of the E-body lid shows remnants of plating 

[6bblgt]

and a few vintage pictures of power disc brake "pilot" car's engine compartments 

[mtull]

https://forum.e-bodies.org/parts-misc-for-sale/9/1970-lid-only-disc-brake-master-cylinder/29220/msg320216#msg320216

pics of E VS B-body lids - inside of the E-body lid shows remnants of plating 

Thank you 6bblgt.  That was the thread I was thinking of ... and thanks for the pics

[Kowal]

https://www.moparaction.com/2023/09/11/pumping-points/

[mtull]

https://www.moparaction.com/2023/09/11/pumping-points/

Great article.  Thanks for sharing. 

[Ricomondo]

https://www.moparaction.com/2023/09/11/pumping-points/

Thats an awesome article - written by our very own @JH27N0B !!