Brake Master Cylinder Swap.

[Clutch]

can you not get rebuilt caliper?. They are not expensive here but I'm not sure about in your country.

I would change the master bleed the brakes and take it for a ride

 

[wnagel]

can you not get rebuilt caliper?. They are not expensive here but I'm not sure about in your country.

Dude.... I live in the extreme of the world....here....has nothing like yours.....yours live in a dream country......here all is too difficult ....( about the american cars...)

Tomorrow arrive my new rubber , and repair parts for my calipers...

 

[Clutch]

Dude.... I live in the extreme of the world....here....has nothing like yours.....yours live in a dream country......here all is too difficult ....( about the american cars...)

Tomorrow arrive my new rubber , and repair parts for my calipers...

Oh!!!! Like having a Chevy in Cuba? I'm guessing so you need to rebuild the parts yourself. I wonder if it's feasible for guys here to ship stuff to you?

 

[pontiacgp]

Dude.... I live in the extreme of the world....here....has nothing like yours.....yours live in a dream country......here all is too difficult ....( about the american cars...)

Tomorrow arrive my new rubber , and repair parts for my calipers...

it was only a suggestion, I'm not dude and I do not live in a dream country. Good luck with your brakes.

 

[wnagel]

Oh!!!! Like having a Chevy in Cuba? I'm guessing so you need to rebuild the parts yourself. I wonder if it's feasible for guys here to ship stuff to you?

I need to repair all with my hand....I,m a automotive electric ....and i work in classic cars ( american 90%), today I work in a impala 2 door 1960, camaro 1975 and the real nasty , (I hate this car), corvetter 75 ( this car is a 70% plastic, fiber....etc....).

I pay and pay and pay for any parts......🙁🙁

If someone can collect and send to chile, maybe he can make some money and help me ....

 

[wnagel]

it was only a suggestion, I'm not dude and I do not live in a dream country. Good luck with your brakes.

Sorry I`m use a wrong sentences.... apologize....!

 

[Clutch]

I need to repair all with my hand....I,m a automotive electric ....and i work in classic cars ( american 90%), today I work in a impala 2 door 1960, camaro 1975 and the real nasty , (I hate this car), corvetter 75 ( this car is a 70% plastic, fiber....etc....).

I pay and pay and pay for any parts......🙁🙁

If someone can collect and send to chile, maybe he can make some money and help me ....

That's too funny I hate Corvettes I cringe when they come in the shop and hope they don't give them to me to fix lol

As far as shipping you parts ?????? Shipping may be more than they are worth that may take some research

 

[wnagel]

That's too funny I hate Corvettes I cringe when they come in the shop and hope they don't give them to me to fix lol

As far as shipping you parts ?????? Shipping may be more than they are worth that may take some research

you work in?

For example......

one week ago I buy form rockauto: USD 37 , rubber hose, and caliper repair kit ... Shpping USD50!!!! total USD$87!!!

I would like to buy a rotors...but the weight is so high and the shipping price is ridiculous ....

 

[Monte Cristo]

This link is correct.
http://www.remaninc.com/pdfs/lowdragcalipers.pdf
GM did start using LOW drag calipers in 1980, most likely the new front wheel drive plate forms. Low drag calipers and step bore master cylinders were not used on g-bodies until 1982. This is a fact.

Right, so there was more than one type of caliper, but the parts vendors only list one. My main point.

I would also recommend 3/16" line for the entire brake system (if redoing your lines and using a different master cylinder), but that is not what GM did and it doesn't make any sense other than to keep assembly line workers from screwing in the fitting into the wrong master cylinder outlet. If the line fitting is 9/16-18, the line is a 1/4" in diameter or larger. The volume of fluid moved through the brake system is dictated by the bore and stroke of the master cylinder and not the size of the line.

Well that makes as good an explanation as any for why there is 1/4" tubing going from the m/c to the proportioning valve. I am assuming that the lines from the proportioning valve to the rear hose and then the lines from the hose to the rear drums are all 3/16". If so, it's not correct to say the rear lines are 1/4", since its just the one short line. Yes, it would be a marginal improvement to replace the 1/4" line with 3/16", and more so if it is rusty.

In my opinion, because of my experience with working with people everyday on their brake systems and working with manufacturer parts, I have a hypothesis. My hypothesis is that the only thing that makes a metric caliper LOW drag is the seal. I may be incorrect, but from my experience and observations it seems to be true.

That's not what the diagram in the link shows, or the text. Maybe you could actually find one and take some pics for your website?

It makes no sense to me why a reman company would mix and match castings with different seal grooves with a high potential of returns and liabilities.

Poor quality control would be the most likely explanation.

If a customer has a 1982-1997 vehicle that uses metric calipers (1982-1988 G-Body, 1982-1992 F-body, 1982-1997 S10 Trucks and SUVs) and they want to stay with the stock front brake system, I tell them to buy reman calipers so it will work with the strait bore master cylinder that is included in my manual brake conversion KITS.

It's still a crap shoot. I just want to know for sure what model caliper I am buying, and buying new should insure that both are the same model at least.

The new Raybestos calipers PN FRC4125N and FRC4126N are new additions. Thanks for finding those. These are most likely the same caliper that AFCO sell for $49.99 (PN 663-5003 and 663-5004). I am not sure if they are LOW drag or NON low drag, but to work for all 1978-2003 vehicles, they need to be NON low drag, normal calipers.

Hey, no problem. I enjoy having a reasoned discussion about the issue. Again, it isn't quite clear. They should be clearly labeled.

Back to the wnagels' original post. "It is possible to remove the original master cylinder and put the most modern without change the brake lines, pipes or servo?" Yes...
...I am a big believer in doing a single change to the brake system and then making sure that change is working correctly. I do not like the idea of making multiple changes to the brake system, finding a problem, and then not knowing which change made gave you the issue.

Some good solid advice here.

 

[Monte Cristo]

I never said the front wheels won't lock up, I said the front brakes will not cause a car to spin. Even on an icy road the front end pushes when you apply the brakes. You claimed that one caliper grabbing first turned your car 180. Tires will not grip enough to make the car pivot on a front tire. It is the back end that turns the car around and many times that is from a driver's error. Here is what happens to a G body when one front wheel locks up and this is with a performance tire that is pretty sticky..
View attachment 73621

The physics of what makes a car spin out are well known. That is that car body first gets pulled out a straight alignment relative to the direction of travel, and then the rear wheels lock up before the front, causing the car to rotate/spin. So, in this case, as noted in your picture and text, a front brake malfunctions and pulls the car to one side. In your case, from your story, it just happened spontaneously. You had no car, person, or deer in front of you causing you to brake hard and apply the rear brakes. You were also fortunate, in that your car was pulled to the shoulder and not into oncoming traffic. In my case, I had to stop or hit the deer. So, the front left brake applied harder than the right pulling the car to the left, and the rear brakes locked before both front brakes, and that threw the car into a counter-clockwise spin into the oncoming lane. It's a bit beyond the scope of this thread, but if you want to convince engineers and physicists that they are wrong, there is a discussion with diagrams here:
https://physics.stackexchange.com/questions/55939/wheel-locks-and-spinout
When you can convince them that they are wrong, you might convince me. It is and was clear to me that the problem was one front wheel pulling the car to the left while braking on a straight road, and then everything else followed. Since it was shortly after the front brakes were replaced, I suspect them.

You are also incorrect to state that a car that spins pivots on its tires. A spinning car pivots around its center of gravity, which is normally around the passenger seat.