Power Brake Disc Conversion

[Dartman72]

Great feedback thanks! Earlier I described mounting the driver side caliper on the passenger side to check spindle and rotor and it checked out great. Good spacing and smooth operation. It is definitely the caliper and I suspect as some have expressed it was poorly machined.

 

[Dartman72]

So is the issue that it's offset or not parallel?
Can't really tell from the picture.
If it's offset then you should be able to adjust the spacers.
If it's not parallel (crooked) then you've got to change parts somewhere.
The casting cleanup grinding does look pretty crappy.

I have SSBC calipers probably from around 2010 or so and they don't look so rough.
They came in a power brake conversion kit but I didn't like the booster/master setup with the Corvette master cylinder.
Mine are setup up with a manual disc/drum master.
They work well.

The issue is it's not parallel - the rotor is centered in the caliper at the bottom (other end) but is offset and rubs at the top

 

[Don Frelier]

The issue is it's not parallel - the rotor is centered in the caliper at the bottom (other end) but is offset and rubs at the top

Recurring theme:

You can't seem to get anything good these days.

 

[RemCharger]

Is it this one?

 

[Dartman72]

Is it this one?View attachment 1561074

looks similar but no. Bleeder is at other end - and outside. You have to bleed with wheels off - weird huh?

 

[RemCharger]

looks similar but no. Bleeder is at other end - and outside. You have to bleed with wheels off - weird huh?

If you look a little closer, the bleeder is on the outside. Not weird because how else would you bleed the outside pistons. They are at the end of the fluid circuit. Bleeder position depends on which side its for.

 

[1STMP]

Sometimes there are.

DoctorDiff Drivetrain Components

This guy is well known with the FABO crowd. So many of the A bodies came with puny 4 wheel drum brakes and were in desperate need of improvement.
Dr Diff, AKA Cass Eslick sells some great stuff. You can choose stock based parts or complete kits or upgrade to bigger and better brakes. I went with 13" front kit that uses modified Ford Mustang rotors and calipers.
View attachment 1560580View attachment 1560581

View attachment 1560582

The 13" kit required the use of a 17" or larger wheel to clear the calipers but Cass has stuff that will fit under a 15" or even a 14" wheel.
He has a great reputation for great parts and great prices.

Agreed that different model
components may be required
to piece together a viable braking
system. Don't be restricted to
name brand as OEM manufactures
spec'd many different suppliers.
I've got Jeep rear disc brakes that
utilize Ford Explorer calipers on
a Mopar rear axle.

 

[Dartman72]

Agreed that different model
components may be required
to piece together a viable braking
system. Don't be restricted to
name brand as OEM manufactures
spec'd many different suppliers.
I've got Jeep rear disc brakes that
utilize Ford Explorer calipers on
a Mopar rear axle.

I want to thank everyone for all the input. To better align with the rotor I used a 1/4' spacer on top (5/16 was original). Before I could bleed the system the replacement caliper showed up and fit sightly better. I bled the system and test drove. It worked as it should but I'm struggling with the manual proportioning valve. I have it fully restricted and can still lock up the rear brakes doing a power stop (from 50 MPH) on pavement - Anyone have any ideas about that? Otherwise operation seems gd. I will never do business again with SSBC-USA, poor quality and worse service - there are better options. I'd rather hear bad news than be lied to.

 

[RemCharger]

Might just need miles to break in the brake pads to the rotors

 

[Dave6T4]

The easiest way is to source front spindles and caliper brackets off an old 5th Ave. or Diplomat. Everything else can be bought new at Car Quest or O'Reilly's.

 

[steve340]

If you are at full reduction on the back brakes you need to get the wheel cylinders sleeved to a smaller size.
If it is locking in the dry it will be bad news in the wet.

 

[RemCharger]

Do some high speed hard braking to burnish in the pads before assessing performance

 

[steve340]

The state of the front/rear shock absorbers and suspension can also affect rear brake lock.
There will always be some weight transfer to the front end - that is not avoidable.
The car must stay "flat" and not do a big nose dive and transfer the majority of the weight to the front end taking the weight of the rear end causing the brakes to lock.
Assuming the car is not nose diving when the brakes are applied.
More effective front brakes will only accentuate the problem and toning down the rears is the only effective option.

 

[steve340]

You also need to be sure both braking systems are working correctly and the rear brakes and shoes are assembled correctly.

 

[Dartman72]

Thanks - good feedback - The suspension is solid and no "nose dive", brakes are assembled and working correct although I know why that is important to ask. My thought was that the manual adjuster should all but shut off the back brakes, apparently not. I'm getting a positive feel that front disc's are working and it got better as I decreased the flow to the back. I'm all out of adjustment and it still locks up the rear when I slam them on around 50MPH. Although the lock up seems to occur toward the end of the braking process. I've slowed a bunch before they lock up.

 

[steve340]

Ok well it sounds like you have all the basics covered.
The adjustable valve is not a "shut off" valve just a regulator of sorts.
It appears your car is a candidate for smaller wheel cylinders.

 

[Dartman72]

OK, I wouldn't object to that - putsy but easy to do . How do I know which ones to get?

 

[steve340]

Over here I use a place that just sleeves them down to whatever size I want. That is by far the easiest.
Pull apart the back brakes and dismantle the rear cylinders and measure the diameter of the pistons.
From there I can recommend a size to try. Just note it is a guess based on your feedback.

 

[Dartman72]

Over here I use a place that just sleeves them down to whatever size I want. That is by far the easiest.
Pull apart the back brakes and dismantle the rear cylinders and measure the diameter of the pistons.
From there I can recommend a size to try. Just note it is a guess based on your feedback.

 

[Dartman72]

I have a .938 bore, what would you recommend? I saw Rock Auto also had a cylinder with a .906 bore.

Appreciate your help and advice