1959 Cadillac Disc Brake conversion

[Chris Conklin]

N' I'm in no mood to mount a teenage girls' Toyota on my front bumper in a permanent manner...

You need to move farther away from that high school! 

[Bob S]

Hi Ben,
So who are the two candidates you are looking at?  I am thing of adding Disc brakes too. 
Thanks
Bob

[TJ Hopland]

At least if you are in the Cadillac you will only end up with a toyota hood ornament, my recent fading drum close call was in a 66 mustang thats about the same size as the average toyo.  If it was just a sunday driver I may have left it alone but we use the car as a daily driver.  It was not a problem in the 60's when people were slightly smarter and no one could stop but now days its a different game when everyone else has 4 wheel disc, abs, cell phone, and no self responsibility.   

[STDog]

It was not a problem in the 60's when people were slightly smarter and no one could stop but now days its a different game when everyone else has 4 wheel disc, abs, cell phone, and no self responsibility.   

I don't think people were smarter, they just knew different things.

The real problem is the last one.

[Sweede64]

The wheels don't fit, the caliper is in the way. Reading your story (funny bdw) it strikes me you need a front end checkup. The behavior you describe is typical to a loose or wrong aligned front end.

Big rigs of today don't have drumbrakes, discs are far moore effective and cools down more rapidly. The lack of frictionarea is compensated whit higher pressure, check the area in a caliper piston and compare it too a wheelcylinder. The retardingforce is at least the same but in most cases discs ecseed drums.

If no other mods then the brakes and wheels are made, its easy the build the car back to factory specs and i don't see any problems whit this mod. I think the first us car equipped whit discs was chrysler 1953, they dropped it and continued whit drums since the cystem wasn't appreciated from the byers.

[Ben Acheff]

Well, the two candidates I've narrowed it down to are from NoLimit engineering and ABS Power Brake, Inc. 

NoLimit comes highly recommended, I'm awaiting a reply from them for my application.

ABS Power Brake seems to have exactly what I need at a fairly reasonable price: http://www.abspowerbrake.com/pages/FINAL113.htm

[Ben Acheff]

Oh, just to reply to Swede's concern, no, my front end has had a complete alignment performed recently.  I had all new bushings and ball joints installed (kit from Kanter) and had a professional shop perform the installation and alignment.

The car's a dream to drive, but contending with other motorists in this age of idiots and econo-caskets shows the limits of half-century old braking technology rather quickly. 

[TJ Hopland]

ABS has some stuff I have not seem before.  One thing I noticed in the Buick, Pontiac, Cadillac section.  "These kits allow the use of original wheels by keeping original bolt patterns".    I find that wording strange.   Getting the bolt pattern right is really easy for us since its still used today (i think).  A will be curious to see how the 12" rotor fits.


Here is a shot of a 10.28" rotor in a 60's vintage 14" wheel.  You can see how close it is.


This appears to be a typical wheel design from the 50's and 60's. This one is a 14".  You can see that first step is only around 12" Before discs that extra step seemed to be common design.


These happen to be a Ford.  I dont seem to have any pictures of GM stuff but from what I recall they are very similar.   Im not saying yours are going to have the same design or issues.  Im just trying to point out where the typical fit issues are when doing these types of conversions.

[Sweede64]

Cadillac rims from these days ore made inside out, its not the diameter thats the problem,  (15 inch) the caliper is gonna hit the rim since ther´s no room in the rim for it unless the caliper is moved inwards but then i think there is cclearance issue inwards..

[STDog]

TJ,

I'd like to see the 12" rotor with a 15" wheel of that vintage too.
11" or 11.5" maybe, but 12" is going to be tight.

A lot will depend on the calipers I think. How much bigger are they.
In the picture you posted the caliper looks to be 3/4" thick where it spans the rotor.

Maybe with different materials, a thinner design can be used?

For example,
The Wilwood SRT calipers are designed for a 12.88 diameter rotor, and the caliper is 7.18" from the center line, so 14.36" diameter inside the wheel for clearance.
http://www.wilwood.com/Products/001-Calipers/001-STR/mounting.gif

The Wilwood Billet SL4 for a 12.19" rotor has a caliper radius of 6.81" (13.62" diameter)
and the version for an 11.75" rotor has a 6.65" radius (13.30" diameter)
http://www.wilwood.com/Products/001-Calipers/011-SL4/dwg.gif

[Stewart Homan]

Taking this a stage further - somebody told me that Toyota Supra calipers have all the ABS stuff built in to the caliper - don't know the strength of it but for those that want to go that route...

[Sweede64]

ST Dog,
On my caprice the rotos are 11.85 in diameter, rims are 15 inch. Dont think its gonna a problem whit 12inch as well. (11.85 = 11 300.99 mm 12 in = 304,8 mm) less than 4 mm or 5/32 inch!

Whit other rims, 12 inch rotors is no problem, the caprice rims fits the cadillac 5 on 5 boltpattern.

[Ben Acheff]

Interesting...I used to have a '93 Caprice Classic.  I should have paid closer attention to the rims on that car before I sold it.

Spoke with ABS Power Brake today, the guy on the phone said that I can indeed use the stock rims and the calipers should clear it.

Think I'm going to take the plunge with kit #821 here: http://www.abspowerbrake.com/pages/FINAL113.htm

I'll let you guys know how it turns out.

If it's good, I'll say so. 

If I die in a fiery wreck, I might be silent for a while...

[STDog]

ST Dog,
On my caprice the rotos are 11.85 in diameter, rims are 15 inch. Dont think its gonna a problem whit 12inch as well. (11.85 = 11 300.99 mm 12 in = 304,8 mm) less than 4 mm or 5/32 inch!

What year Caprice?

Go ahead, try putting you '64 wheels over the Caprice's discs. Bet ther don't fit.

The 68-70 Cadillacs use 12" (11.96")  rotors, and the 71-76 (maybe later) use 11.86" rotors. But all use a different wheel than the earlier drum only wheels so they will fit over the calipers.

That is the whole point of this discussion.

[Sweede64]

The caprice is -93, read my post again and understand it.
The issue was clearance due to the diameter of the rotor, as i stated before the caliper wont clear the stock unless the uoter surface of the rotor is outside the caliper. The diameter in the stock cadillac rim is the same as the caprice but the center is flat and does not have a bulge for the caliper.

[STDog]

I said the drum wheels would not fit because of clearance for the caliper.

You said a stock wheel would be fine because you 1993 Caprice used 12" rotors.

I pointed out that the the 70s Cadillacs also used a 12" rotor, and they had a different wheel to gain clearance for the caliper.


My understanding is the inside of the wheel is shaped differently and there is not enough room inside for the calipers.
It's raining now and I'm not getting out in the rain to measure the inside of a disc and a drum wheel in order to detail the differences.

Maybe in a few days it'll dry up enough.

[Sweede64]

Ok Dog, i qute my self from an earlier post

Cadillac rims from these days ore made inside out, its not the diameter thats the problem,  (15 inch) the caliper is gonna hit the rim since ther´s no room in the rim for it unless the caliper is moved inwards but then i think there is cclearance issue inwards..

And thats it för today, have i nice one.

[Ben Acheff]

Okay! Time for the follow up!

In case anyone's been waiting with baited breath for the results of this endeavor, fear not! 

Seriously though, the project is finished, n' I've been driving the car since Sunday.  While my many talks with late 50s-early 60s Chevy owners who have done the disc brake conversion amounted to "It's so easy!  I did it in a weekend!  You should like, totally do it!" of course, the results for a Cadillac are -wildly- different.  (Those pesky Chevy guys have it so easy) Erf.  Had to fabricate all new lines from the front of the car all the way to the back axle, had to replace the rear distribution block, had to modify my existing forward distribution block to work, had to take a dozen trips back and forth to various auto parts stores to gather additional supplies that the kit made no mention of. 

As for the kit itself....jeez....the -most- amateur attempt at instructions I've ever seen!  A single, blurry page that was riddled with typos (even mis-spelled "washer") no mention of even simple things like torque specs, the fact that there are different spacers that can only go in certain locations, etc. etc.   Don't believe me?  Check out some samples of their instructions from other kits posted on their site: http://www.abspowerbrake.com/product.php  Had to waste most of the time talking to someone in California who barely spoke English to convince them that some of the parts that they provided would not work.   Rather than getting a proper right hand thread/left hand thread set of castle nuts, I got two right hand thread ones...the passenger side brake hose provided is no where near long enough, I ended up clearing out the entire area's stock of late '80s GM pickup passenger side brake hoses to modify something to fit, etc. etc....ad infinitum.

Of course, this was all after this idiot company lost my order for two weeks, n' I was stuck with a car half taken apart on jack stands, resulting in my missing 4 car shows.

Now, having said all that, I've gotta say.......TOTALLY WORTH IT! 

It might have been a month's worth of weekends in headaches and cussing, but.....WOW.   The car stops better than my old Chevy Caprice did.  Seriously.  I wasted hundreds of dollars and years replacing/rebuilding nearly every component of my original half-century old brake system to just keep ending up with mediocre braking results that would leave me white-knuckled in traffic.  I've got less pedal travel, the dual-diaphragm booster requires far less effort than my rebuilt original needed, I'm still in kind of awe at the night/day difference!

I didn't even have to replace my stock rims!  Something I'd been terribly afraid of from the get-go. 

Couple of quick points, though; I've found that you will need to fabricate a new bracket to move your existing washer jar assembly to the side and down to continue using it.  Also, you might as well install a new set of spark plugs on your car while you're doing the conversion, because the area on the driver's side is going to get a -lot- more cramped with the longer booster/mc and changing plugs after the install is going to be a lot more tricky.

[35-709]

Good deal on getting it done Ben.  I wonder if the No Limit Engineering setup would have been better and more complete.  The Street Rodder article on the No Limit kit was quite complementary.
Geoff

[Ben Acheff]

That's a good question...the only reason I went with ABS Power Brake Inc. was because I didn't hear back from No Limit.  I suspect they may have lost my emails during whatever system outage caused their site to be unavailable for a couple of days.