68 Charger multiple brake issues

[BDnFL]

Originally power drum all around.
Converted to disc front drum rear by shop. Wilwood front disc with master cylinder. New drums in rear.
Thanks to a member here I see I have an A Body booster with a stand-off from firewall. See pic.
Brakes terrible so I started investigating and found Residual Valve in backwards.
I then pulled master cylinder to check rod length. Rod at least 1/8 long. With it adjusted all the way in.
So here is my questions: Can the A body booster be used?
With master cylinder removed I lightly pressed brake pedal and felt a spring tension on pedal, is this normal ?
Summit does list the A body style with firewall stand-off bracket for B body.
Hopefully it can be used because repiping the master and proportional might be beyond my scope due to access.
Thanks

 

[Sixpactogo]

I put one of those POS boosters on my Niece's 70 Challenger years ago when I restified it. I don't know why they even sell them with the belief they are usable. I doubt anyone would be happy with their performance. I believe you need the dual 8" Bendix unit that the factory installed on these cars when they went to front discs. I swapped one in her Challenger and another one on my 68 Charger. Both work great! The only deviation from the factory units are the boots on these are slightly larger and require a bit of enlarging the firewall hole with a dremel tool or file. Brakes are way too important to be miss-matching parts hoping they will play well together. They seldom do.

https://www.ebay.com/itm/235679793717?

 

[BDnFL]

I put one of those POS boosters on my Niece's 70 Challenger years ago when I restified it. I don't know why they even sell them with the belief they are usable. I doubt anyone would be happy with their performance. I believe you need the dual 8" Bendix unit that the factory installed on these cars when they went to front discs. I swapped one in her Challenger and another one on my 68 Charger. Both work great! The only deviation from the factory units are the boots on these are slightly larger and require a bit of enlarging the firewall hole with a dremel tool or file. Brakes are way too important to be miss-matching parts hoping they will play well together. They seldom do.

https://www.ebay.com/itm/235679793717?

Sixpactogo,
Thanks for replying. I had read some of your previous posts on this booster being junk. I was hoping this wasn’t one.
With the booster in your link can I still use my current Wilwood master cylinder and proportioning valve?

 

[68 Sport Satellite]

There seems to be a flurry of FBBO members with brake system issues in the last month. Watching this one with interest...

 

[Sixpactogo]

Sixpactogo,
Thanks for replying. I had read some of your previous posts on this booster being junk. I was hoping this wasn’t one.
With the booster in your link can I still use my current Wilwood master cylinder and proportioning valve?

I'm not up to speed on Wilwood parts so no help for you there but I would think they would require the same amount of pressure to operate. Most issues with swapping drums for discs involve not knowing that disc brakes require double the amount of pressure and try using a drum booster. I had to learn that lesson myself years ago. With all of the threads on this site involving these swaps, I know I am not alone. Neither are you.

 

[68 Sport Satellite]

My wildwood front discs stop my car just fine. I haven't used their MC though. I'm using a 1-1/8" bore MC Raybestos Blue.

 

[BDnFL]

Thanks for all the above replies.
I called Wilwood. I was number 39 in the queue. Finally make to number one after 20 minutes to find out Wilwood doesn’t make boosters!
I was able to correct the residual valve after shop installed it backwards.
I’m probably going to install my Wilwood MC back on and try to get a decent brake bleed all around. When cooler weather comes I’ll readdress this as the heat is kicking my butt. My car is jammed in the garage where I can’t even get a jack under it.
I book marked Sixpacts suggestion for parts.

 

[RJ Squirrel]

Personally FWIW I would install a 15/16 manual master cylinder and toss the booster.

 

[dfrazz]

Or a hydroboost if you really want to stop well

 

[chrger1967]

I put one of those POS boosters on my Niece's 70 Challenger years ago when I restified it. I don't know why they even sell them with the belief they are usable. I doubt anyone would be happy with their performance. I believe you need the dual 8" Bendix unit that the factory installed on these cars when they went to front discs. I swapped one in her Challenger and another one on my 68 Charger. Both work great! The only deviation from the factory units are the boots on these are slightly larger and require a bit of enlarging the firewall hole with a dremel tool or file. Brakes are way too important to be miss-matching parts hoping they will play well together. They seldom do.

https://www.ebay.com/itm/235679793717?

How did the linkage going to the brake pedal work out for you, did you have any length issues at all? Thats not a bad price, and it comes with the correct plate. I have an all-wheel disc setup in my 67 Charger, and the pedal is spongey, I'm wondering if it's just the M/C and booster combo they used.

 

[chrger1967]

Originally power drum all around.
Converted to disc front drum rear by shop. Wilwood front disc with master cylinder. New drums in rear.
Thanks to a member here I see I have an A Body booster with a stand-off from firewall. See pic.
Brakes terrible so I started investigating and found Residual Valve in backwards.
I then pulled master cylinder to check rod length. Rod at least 1/8 long. With it adjusted all the way in.
So here is my questions: Can the A body booster be used?
With master cylinder removed I lightly pressed brake pedal and felt a spring tension on pedal, is this normal ?
Summit does list the A body style with firewall stand-off bracket for B body.
Hopefully it can be used because repiping the master and proportional might be beyond my scope due to access.
Thanks

View attachment 1912048

Is your setup anything t like this, with a GM style M/C? This is giving me a spongy pedal.

 

[BDnFL]

I have Wilwood master cylinder with an unknown booster.
I have a booster bracket that stand off the firewall.
Here’s a pic off the internet as I have my MC off the car.

 

[Sixpactogo]

How did the linkage going to the brake pedal work out for you, did you have any length issues at all? Thats not a bad price, and it comes with the correct plate. I have an all-wheel disc setup in my 67 Charger, and the pedal is spongey, I'm wondering if it's just the M/C and booster combo they used.

I installed the Bendix dual 8" unit on my niece's 70 Challenger and my 68 Charger. They both work perfectly. The provided linkage is a direct bolt in. As I mentioned in post #2, the only issue I had was I needed to enlarge the firewall hole about 1/8" to allow for the larger than factory rubber boot. IMO, the booster you have is causing all of your issues but I really am guessing at that. You didn't mention if you replaced the metering block with a proportioning valve, but if you did, you more than likely don't need it since you have discs front and rear. I have no idea as to what if any problem you could be having with the master cylinder you have. It appears to have the same size bowls for front and rear so may work well with 4 wheel discs. I see you have the engine side plumbing so if I were you, I would buy this booster and try it with the master you already have since the other one I referenced is the basic unit used for front discs and rear drum. I can't tell from your pic if your master cylinder is a 4 bolt or 2.
https://www.ebay.com/itm/315530919275?

 

[chrger1967]

I installed the Bendix dual 8" unit on my niece's 70 Challenger and my 68 Charger. They both work perfectly. The provided linkage is a direct bolt in. As I mentioned in post #2, the only issue I had was I needed to enlarge the firewall hole about 1/8" to allow for the larger than factory rubber boot. IMO, the booster you have is causing all of your issues but I really am guessing at that. You didn't mention if you replaced the metering block with a proportioning valve, but if you did, you more than likely don't need it since you have discs front and rear. I have no idea as to what if any problem you could be having with the master cylinder you have. It appears to have the same size bowls for front and rear so may work well with 4 wheel discs. I see you have the engine side plumbing so if I were you, I would buy this booster and try it with the master you already have since the other one I referenced is the basic unit used for front discs and rear drum. I can't tell from your pic if your master cylinder is a 4 bolt or 2.
https://www.ebay.com/itm/315530919275?

There is a small metering block, and an adjustable valve was put in for the rear brakes. I have that maxed out. I did find that my pedal had about a half inch of play which was being caused at the clevis pin where the rod from the brake pedal arm to the booster hooks up.

 

[68 Sport Satellite]

I installed the Bendix dual 8" unit on my niece's 70 Challenger and my 68 Charger. They both work perfectly. The provided linkage is a direct bolt in. As I mentioned in post #2, the only issue I had was I needed to enlarge the firewall hole about 1/8" to allow for the larger than factory rubber boot. IMO, the booster you have is causing all of your issues but I really am guessing at that. You didn't mention if you replaced the metering block with a proportioning valve, but if you did, you more than likely don't need it since you have discs front and rear. I have no idea as to what if any problem you could be having with the master cylinder you have. It appears to have the same size bowls for front and rear so may work well with 4 wheel discs. I see you have the engine side plumbing so if I were you, I would buy this booster and try it with the master you already have since the other one I referenced is the basic unit used for front discs and rear drum. I can't tell from your pic if your master cylinder is a 4 bolt or 2.
https://www.ebay.com/itm/315530919275?

Since yours is working well, for my reference, when you press the brake pedal, even if the pedal is not spongy, does it feel extremely light? How far from the top of pedal travel does it engage and start to feel firm?

 

[Sixpactogo]

Since yours is working well, for my reference, when you press the brake pedal, even if the pedal is not spongy, does it feel extremely light? How far from the top of pedal travel does it engage and start to feel firm?

I no longer have access to my Niece's Challenger but I tested my Charger and my 2005 Chrysler 300. Both pedals will go down about 1" before becoming firm. Engine running or not. My 65 Fury has power drum brakes and has a bit less pedal movement before becoming firm. None are spongy. If you have spongy brakes IMO, you have air somewhere

 

[chrger1967]

Since yours is working well, for my reference, when you press the brake pedal, even if the pedal is not spongy, does it feel extremely light? How far from the top of pedal travel does it engage and start to feel firm?

Well, I did find a problem with the linkage for the booster to the pedal arm. I had to put in an adjustable rod from the pedal arm to the booster, the rod setup that came with the kit that was put in was way too long, the pedal was practically hitting my knees. The clevis that I used was causing way to much slack and play at the clevis hookup. So, I found a better way to hook it up, but the only thing was, the clevis pin is 7/16 and the clevis I used is 3/8, so I drilled it out. No more slack or play, it's nice and tight, without being too tight. Now I have to cut the threaded rod as the whole setup is about an 1 1/2' too long. I'm sure you know how that goes, you change one damn thing and it fooks up everything.

 

[chrger1967]

I no longer have access to my Niece's Challenger but I tested my Charger and my 2005 Chrysler 300. Both pedals will go down about 1" before becoming firm. Engine running or not. My 65 Fury has power drum brakes and has a bit less pedal movement before becoming firm. None are spongy. If you have spongy brakes IMO, you have air somewhere

Does your Fury have bucket seats and a console? I was a UPS driver in Brooklyn, and at a school on my route on Stillwell Ave, there was a 65 fury. It was light blue, with a blue interior with bucket seat and a console. I left my number on that car, but no one ever called. It must have been a teacher or student at that school. It was a cool car.

 

[Sixpactogo]

Well, I did find a problem with the linkage for the booster to the pedal arm. I had to put in an adjustable rod from the pedal arm to the booster, the rod setup that came with the kit that was put in was way too long, the pedal was practically hitting my knees. The clevis that I used was causing way to much slack and play at the clevis hookup. So, I found a better way to hook it up, but the only thing was, the clevis pin is 7/16 and the clevis I used is 3/8, so I drilled it out. No more slack or play, it's nice and tight, without being too tight. Now I have to cut the threaded rod as the whole setup is about an 1 1/2' too long. I'm sure you know how that goes, you change one damn thing and it fooks up everything.

You don't by chance have a Midland booster do you? I know they used a spacer / filter in between the booster and master cylinder that was about 1/2" thick.
The Bendix booster didn't use that spacer. It might explain why the rod was too long.
As for my 65 Fury, Yes it has bucket seats and console. It is the Sport Fury. All Sport Furys got the bucket seats and console with the floor shifter.

 

[Casca2525]

you guys are all lucky, Watford Wonders booster and master cylinder are turned 90 degrees to the left, both need changing for the safety