Settle a brake argument

[pagrunt]

I wanna see where this is. The parts book shows M/T brake pedals, but they're for power brakes. Now, I can find manual brakes for 77 on back. But nothing for 78-up. Again, there's no adapter listed anywhere I can find.

I reiterate I'm not saying they never made any with manual brakes, I'm just trying to verify which cars actually came with manual brakes and more importantly, how did they do it? Like what parts or did they have a different firewall, etc., etc.

For the '78 Malibu & Monte Carlo power brakes option was still listed under J50 on non-A/C V6 cars, all wagon's & El Camino's regardless of engine had power brakes standard, all A/C or V8 Malibu's & Monte Carlo's had it as a required option. I'll have to dig deeper to see when they became standard across the board & parts listed. As for the brake pedal it had a manual transmission pedal in place of the used with a automatic. I'll have to compare my pedals to see the difference with push rod holes.

 

[Bonnewagon]

My '81 Malibu wagon was as base as it comes. 229, 3 speed manual trans, no AC, bench, manual everything. And it had power brakes.

 

[malibudave]

Manual brakes came on 78, 79, and maybe 1980 GM "G-bodies". It had a stamped steel plate to cover the hole, a push rod retention cup, a push rod that had a special head on it to be retained inside the push rod retention cup so it would not fall away from the back of the master cylinder, and usually a different brake pedal with a smaller foot pad. They came with a 7/8" bore master cylinder from the factory. The master cylinder looked identical to the power boosted master cylinder which has a 24mm bore size. The master cylinders did not have a hole in the back of the piston to retain the push rod, so the special push rod was used along with a special push rod retention cup.

 

[69hurstolds]

Manual brakes came on 78, 79, and maybe 1980 GM "G-bodies". It had a stamped steel plate to cover the hole, a push rod retention cup, a push rod that had a special head on it to be retained inside the push rod retention cup so it would not fall away from the back of the master cylinder, and usually a different brake pedal with a smaller foot pad. They came with a 7/8" bore master cylinder from the factory. The master cylinder looked identical to the power boosted master cylinder which has a 24mm bore size. The master cylinders did not have a hole in the back of the piston to retain the push rod, so the special push rod was used along with a special push rod retention cup.

So rare they didn't catalog any parts for it in GMSPO, apparently. None that I can find anyway. I'm still searching for part numbers for anything manual and coming up empty.

Anyone got any dealer ordering books or a window sticker, RPO codes, etc.? This is intriguing.

 

[olds307 and 403]

I owned a 77 Dodge Van, factory manual brakes. It was a harder pedal with less travel. Of course it may have been the seized calipers which is very common on those years of Dodge cars and trucks. I actually destroyed two rotors, we cut the worst one for the heck of it, paper thin after cutting out the damage.

 

[malibudave]

Here is a link with a picture of a stock manual brake conversion plate, master cylinder, retention cup, and push rod.

Factory Manual Brakes Question

I went to the pick n pull today and got some parts off a wrecked 1978-1980 Malibu that I saw on a previous trip. It had what looked like a factory manual brake set up so I grabbed the master cylinder and block off plate. The block off plate was a thin 2 piece sheet metal covering, and inside...

gbodyforum.com

What part numbers are you looking for?

 

[69hurstolds]

What part numbers are you looking for?

All of them, of course.

 

[Bonnewagon]

Manual brakes are not what most people think. By using a small master cylinder bore the pedal travel increases but the pedal effort decreases. You can get the manual pedal to feel the same as the power pedal by using the right parts. Before disc brakes were common you had four wheel brum brakes. Drum brakes are self-actuating so the more you press the brake pedal the effort decreases. When early 4 wheel drum cars were first power boosted if you were not careful you could put your head right through the windshield. But the enemy of drum brakes is heat which results in brake fade. Thus disc brakes are way better in that regard. You get into trouble by taking away the power booster but leaving the larger bore MC that came with it. Then you are trying to force a too large amount of fluid through a tiny hole. Pedal travel is less but effort is high. Power reduces the effort and removing the booster leaves you with a high pedal effort that feels like you need three feet to press the pedal enough to stop the car. So even with 4 wheel disc brakes that have zero self-actuating action, it is possible to use a small enough bore MC to get pedal effort down to a comfortable level. The high pedal travel can be addressed by changing the pedal geometry to reduce travel but then effort may go up. It is a fine balancing act that takes a lot of thought and testing to get right. Race car builders confront this all the time and they have it down to a science. Adapting to the street is difficult because of the limited selection of factory parts we have to use.

 

[pontiacgp]

I have read that women played a big role in putting power brakes in cars and the vanity mirror

 

[Bonnewagon]

And automatic transmissions.