Need picture of 1974 1975 brake booster or seller of one

MN72Fury

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I have a 1972 fury with a 1974-5 Imperial rearend

The rearend and brakes all rebuilt with much effort and expense. I have a ram man booster and do not have enough vacuum on the rear disc brakes. Is there someone who has a 1974-5 imperial with rear disc that can take picture of the booster and ideally the rear of one if someone has one out of the car.

I am looking for solutions and may need to buy a 1974-5 booster if they can be found

Thanks
 
Distribution block may be different for 4 wheel disc brake cars too.
 
I have a 1972 fury with a 1974-5 Imperial rearend

The rearend and brakes all rebuilt with much effort and expense. I have a ram man booster and do not have enough vacuum on the rear disc brakes. Is there someone who has a 1974-5 imperial with rear disc that can take picture of the booster and ideally the rear of one if someone has one out of the car.

I am looking for solutions and may need to buy a 1974-5 booster if they can be found

Thanks
Here's the thing, if you have enough vacuum on the front brakes then you have enough vacuum, the power booster works on boosting the master cylinder, it doesn't differentiate between the reservoirs in the master cylinder. Your problem is something else, either a bad brake hose, clogged distribution block or line, or maybe you need a proportioning valve for the rear. I would be looking at the hose first if it isn't new, then checking to see what differences there are in distribution blocks between the years.
 
You could get a cheap dial type prop valve from summit for around $30 (same thing as the wilwood piece but the name and price). Plum it in line with the rear brakes and dial it in. Easiest route to go.
 
I have a 1972 fury with a 1974-5 Imperial rearend

The rearend and brakes all rebuilt with much effort and expense. I have a ram man booster and do not have enough vacuum on the rear disc brakes. Is there someone who has a 1974-5 imperial with rear disc that can take picture of the booster and ideally the rear of one if someone has one out of the car.

I am looking for solutions and may need to buy a 1974-5 booster if they can be found

Thanks
Lots of good advice in the thread so far... you did not make your life easier with this swap. I may be able to help with some pictures and/or part information. I do hoard the disc cores, and am not real interested in selling my tougher finds... not that they're worth much anyhow.

I have to go to work, but if you would like to detail the parts you have used, I'd be interested enough to dig through some parts and service manuals for you. BTW, I haven't dug in this deep, but there are several factory versions of some of these parts listed in the parts books. I haven't figured out all of the reasons why, but 75 Imperials had the self leveling rear suspension and some different hardware...
 
Lots of good advice in the thread so far... you did not make your life easier with this swap. I may be able to help with some pictures and/or part information. I do hoard the disc cores, and am not real interested in selling my tougher finds... not that they're worth much anyhow.

I have to go to work, but if you would like to detail the parts you have used, I'd be interested enough to dig through some parts and service manuals for you. BTW, I haven't dug in this deep, but there are several factory versions of some of these parts listed in the parts books. I haven't figured out all of the reasons why, but 75 Imperials had the self leveling rear suspension and some different hardware...

I appreciate your thoughts. I really like the rearend, (I think) but I have had real issue getting the NOS rear discs and ebrakes and hard ware. Now all that works but have issues with vacuum. It could also be the new motor with low vacuum due to the cam. I am fortunate to have MOPAR shop called RT garage working on the car they are very good but are scratching their heads on the brakes. He is doing some diagnostics on the proportioning valve. I will keep you updated. I may need more advice. I think I got some brake part from Wolfen - thanks
 
I appreciate your thoughts. I really like the rearend, (I think) but I have had real issue getting the NOS rear discs and ebrakes and hard ware. Now all that works but have issues with vacuum. It could also be the new motor with low vacuum due to the cam. I am fortunate to have MOPAR shop called RT garage working on the car they are very good but are scratching their heads on the brakes. He is doing some diagnostics on the proportioning valve. I will keep you updated. I may need more advice. I think I got some brake part from Wolfen - thanks

If the new engine has a ``wild`` cam, you may have to install a vacuum canister, like 78Brougham has in his 78 NYB.
 
Have you got the 74/75 Imperial only 50-50 master cylinder?
 
Have you got the 74/75 Imperial only 50-50 master cylinder?
NO!!!

That is the answer I need is there a special one. The one listed online do I need a special booster and master? The booster is "Out of stock" - any ideas?
 
I gotta ask, whose idea was the Imperial rear end, yours or the shops?
 
Mine, thought it would be simple. Ha. It is beefy and nice and I wanted the 4 wheel disc and 3.23 limited slip. In hindsight it has been a headache. The seller is the one who told me how easy it would be.

Now it is in and rebuilt and I paid for the NOS discs, parts for ebrakes, etc. I hope I can get it work well.

The older I get the more I realize every thing in the world is complicated. Youthful ignorance allowed me to work on these cars without knowledge, tools or money. I still learn the hard way.
 
Have you got the 74/75 Imperial only 50-50 master cylinder?
I just purchased a 74/75 master cylinder that was on ebay NOS, but I will need a booster in stock that fits. Or used an have rebuilt
 
I just purchased a 74/75 master cylinder that was on ebay NOS, but I will need a booster in stock that fits. Or used an have rebuilt
If the new master cylinder fits your booster, you have no need for a new booster. The booster simply boosts your brake pedal, that's all it does, nothing complicated there.
 
Mine, thought it would be simple. Ha. It is beefy and nice and I wanted the 4 wheel disc and 3.23 limited slip. In hindsight it has been a headache. The seller is the one who told me how easy it would be.

Now it is in and rebuilt and I paid for the NOS discs, parts for ebrakes, etc. I hope I can get it work well.

The older I get the more I realize every thing in the world is complicated. Youthful ignorance allowed me to work on these cars without knowledge, tools or money. I still learn the hard way.
You're almost there, just get the master cylinder you need, and it should work. I don't know if you'd need a specific booster, maybe a disc/drum off a C body, not imperial specific, to make it all play nice together. Still have to see this car, we had two '72's at Farmington this past June, a new record! (Both owners are members of the F_BO family too.)

A26E3BD2-7FC6-4F7F-B5CD-637B996B51A0.jpeg
 
Have you got the 74/75 Imperial only 50-50 master cylinder?
Thank you Mr C.

@MN72Fury ... the 50/50 master is so the rear brake circuit won't run out of fluid, it isn't so special otherwise. It is possible to use a rear drum master from a Formal (and many other cars) but you want to remove the residual pressure valve from the port (if one's there). This stuff is shown in the FSM, but for repair purposes... don't expect a tutorial for modifications.
MC1.jpg

Metering valve could cause the opposite effect of what you described
MC2.jpg

I think someone else mentioned checking the hoses... don't bother if they're old, just get new ones. A brake hose can fail internally and a little flap of rubber can act as a valve to block or hold pressure... a pretty common problem with an old or abused hose.
 
You're almost there, just get the master cylinder you need, and it should work. I don't know if you'd need a specific booster, maybe a disc/drum off a C body, not imperial specific, to make it all play nice together.
Specific would be less important than having a proper booster for the car. The dual diaphragm booster used on the Imperial was to provide a greater amount of pressure than a similarly sized single diaphragm booster could, a larger single diaphragm may provide enough... but now someone would have to do math.

Booster sizing is exactly the same concept as piston sizing, it's all fluid pressure and the sizing will determine how much pressure is multiplied. There is also the issue of how much leverage is provided by the pedal assembly, some of these cars had different pedal assemblies to provide different travel and pressures. Mix and match components may work, to some degree... but you can make an unsafe situation creating something that seems "good enough" until you need to panic stop.

Another set of master cylinder pics from the parts book:
MC3.jpg
MC4.jpg
 
Mine, thought it would be simple. Ha. It is beefy and nice and I wanted the 4 wheel disc and 3.23 limited slip. In hindsight it has been a headache. The seller is the one who told me how easy it would be.
Imagine that... a seller letting you know how easy stuff will be to do... :lol:
 
Mine, thought it would be simple. Ha. It is beefy and nice and I wanted the 4 wheel disc and 3.23 limited slip. In hindsight it has been a headache. The seller is the one who told me how easy it would be.

Now it is in and rebuilt and I paid for the NOS discs, parts for ebrakes, etc. I hope I can get it work well.

The older I get the more I realize every thing in the world is complicated. Youthful ignorance allowed me to work on these cars without knowledge, tools or money. I still learn the hard way.

The rear disc brake axle is not simple! I think that even axle shafts are different when compared to a rear axle with drums. I don`t have to say that you may be able to find reproduced gear sets and Sure-Grip units and that`s it.
 
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