As for the "modern car" performance expectations . . . you also have to remember that modern cars are not designed to lock-up the brakes, not just from an ABS situation, but from some other evolutionary design changes. Like more of a frontal bias in the brake pressures, as I recall. Lining composition is probably another.
Back in the 1960s era when just a toe was needed to stop the car, GMs tended to be more sensitive in that area than Chryslers usually were, but there was still enough power to lock the wheels, all four in many cases, although the road tests noted the rh rr wheel was mostly a Chrysler trait of the time, it seems.
Back then, the "best" brake job would include turning the drums to a smooth surface and then usually "grinding" the shoes to match (arcing them). Most of the name brand shoes stated they had enough "meat" to do that with their shoes. BUT we never had or needed to get that done on the many drum brake shoe replacements we had done back then (usually by the good mechanic at the Gulf Station where we bought gas for years. It was presumed that other locations did similar (no arcing). Nor did anybody really have the machine to do it, by observation. BUT we always knew to not get into a situation where we needed to make a panic stop a (good practice anyway) for several days. If there might have been some mis-match of the diameters, it all worked itself out before long, I suspected.
Granted, in N TX, there are not a lot of "tall hills", but a good number of curvy country roads, so constant brake use does not usually happen. It was easy to see who might be "riding the brakes" as the brake lights were always on, too. BUT, with a then-70mph speed limit, high-speed Interstates and some great state highways were the norm. A good driver could see what was coming and slow down before it happened, usually.
When we got out '69 Chevy pickup, when new, it had poorer brakes than the Chrysler did, by a long shot. I could fade them just by driving a bit more agressively in town, things the Chrysler would never had done. So driving the pickup "easier" was necessary. And this was unloaded! The pickup definitely needed "more brake" than the stock 11x2 power brakes (the seemingly standard size brakes on many larger GM vehicles back then). Can't forget the issue with drum brakes of driving through water, which would wipe-out the braking power of the GM drum brakes (power or not), as Chrylsers just needed a cautionary "ride the brakes lightly" just afterward, from my experiences. Going to front disc brakes was a big improvement in GM brake performance! Although they still had performance issues which the car magazines didn't mention, but I experienced with my then-new "77 Camaro LT.
Now, all of these experiences were BEFORE the feds got involved to put pedal pressure standards on vehicular brake systems and well before "disc brake dust" was an issue in the middle 1970s. Much less anti-lock stuff, which came later.
In the earlier 1960s, I had an aunt and uncle out in West TX that liked to go to Ruidosa, NM to the races. They traded a '59 Impala for a '63 Polara 2-dr hardtop on the recommendations of many of their friends . . . due to the fact you could put the TF in manual "2" and drive through the mountains without using nearly as much brake. Those earlier TFs had a "more direct" torque converter and it would use the engine to control speed rather than just the brakes. They loved the car for that.
Many generations later, now, we are in a disc brake world. Everything which seemed to come before that is now allegedly "junk", although when that was all we had, it was not "junk" by any means, but better than what the competition usually had. The earlier "Total Contact Brakes" was a complicated situation for Chrysler, although it was probably a better design in some aspects. Especially as it had an adjustment and wheel cylinder for EACH brake shoe.
Brake fade was an issue with drum brakes, but apparently not for the full-metallic police-spec brake shoes that Chrysler used back then. Read the article on the CHP tests in the "Squads" section of
www.allpar.com, by "Curtis Redgap". But those full-metallic shoes needed heat to operate at their best. As most of the owners of the original '61 Impala SS 409 owners removed then so they could stage the car at drag races (with normal brake shoes).
There seemed to be brake shoe tests of the multitude of brands of brake shoes which were available back then. One test used a '60 Ford Galaxie for its test vehicle, with its 11x3 front brakes. Pictures and data. There was some very bad shoes, back then, as there were some very good ones, too. BTAIM
Sometimes, I wonder how we lived through that time. No seat belts, drum brakes, bias-ply tires, etc. With the only cup holders being on the inside of the glove box door! But many of us did it, so far.
I fully understand the benefits of power disc brakes . . . and have since the middle 1960s. I also understand the magnitude of the conversion process, too. Plus that spending a little bit to get things working well now with the drums can delay the conversion timeframe a bit. ONE thing is to ensure, repeat ENSURE, that the disc brake components are all matched to the vehicle (booster, master cyl, brake calipers, etc.) rather than a more universal-fit situation. A friend in our Mopar club had bought a booster/master cyl for his mid-60s B-body from a well-known speed shop, but now the brake pedal was very sensitive to input, unlike the OEM parts he replaced. He got a more universal pair than one specifically designed for his vehicle from an aftermarket supplier, as it turne out.
I have a friend in Oregon who was doing all of the upgrades to a '56 Buick he inherited, including doing the popular dual-circuit front disc brake upgrade. He got the recommended items, which had to be adapted, including the under-floor master cyl. After trying to make it work, for an extended period of time, he went to the salvage yard and got OEM drum brake parts and now everything works as it should. But that model of GM car has its own issues in many respects, too, which are not really conducive to such an upgrade. BTAIM One observation was that a college prof was mentoring him on the hydraulic issues of different sizes of pistons and such in the disc brake situation, which might have been a contributing factor in trying to get everything matched correctly?
Sorry for the length. Many thoughts and experiences,
CBODY67
