Disc brake conversion

Anyone who has experience with converting to discbrakes ? - Iv'e seen kits from a company called Direct Fit brakes (Arizona).
When braking down from high speeds more than once in a short period i have a problem with fading brakes, and this kit includes a new double mastercylinder with vac. booster (not on my current single master) + regulating valve & fittings, all a resonable price.

I've been looking into doing a conversion too. Good brakes are a MUST and the old drums just don't cut it in my mind for these big cars. Any info people have would be great.

There is a guy on ebay that sells the kits for about 800$ i think??? I've never measured the drums on our Pontiacs but I know my Buick has 14" finned, aluminum drums that have absolutely no problem stopping those big ass cars. There have been a few people on buick-59.com that have mentioned wanting to convert to disc brakes. The conclusion on every single thread was that those huge drums were plenty to stop a 4800 lb car and the tons of money and work were not worth it.

I don't think the Pontiacs had 14" drums but they also weigh less. I think with a completely gone through OEM brake system our cars will stop fine. Keep in mind I'm guessing since I have never driven my Pontiac. My Buick never had any problems and I never touched the brakes.

I will say that the only reason I would convert to disc brakes would be the ease of them. I hate messing with all those damn springs on drum brakes.


Also, the kits that I have seen have a note that says that stock rims will not fit because the calipers will hit the rim because of the size of the discs. That's what kept me away. I want to use my original hubcaps.

I think the kit price was 600 $ - i don't recall any restrictions on stock rims, but they did state that other rims might cause problems.

The buick drums are alu, and i think the pontiac brakes are 11" - so they are properbly alot better at resisting the heat. Try stopping the car fast from 120 mph, or stopping with a caravan from 60 mph. It may work the first time, but there are no reserve stoppingpower left, at least not with the pontiac brakes.

I checked DF brakes, but though they have sold 'old pontiac' kits on e-bay the product is not listed at their site. None at e-bay at the moment.

This is the one I was refering to. http://cgi.ebay.com/ebaymotors/1959-66-67-68-Pontiac-Bonneville-Catalina-DISC-BRAKES_W0QQcmdZViewItemQQcategoryZ33564QQihZ021QQitemZ310059046822QQrdZ1QQsspagenameZWDVW

I don't know if I emailed him or if his listing has changed but If I remember correctly he said stock rims wont work. Our rims are only 14" which doesnt leave much room for a big disc or calipers. Maybe I read it wrong and stock rims do fit. But I do remember that being the reason I changed my mind

OK. that was the one i looked at too. I can't find any remarks about the stock rims, but i guess if you already chrecked it there is no reason to continue. I've got brand new wide whites on the original rims, and original hubcabs, and i am not about to scrap that just now. I bought a set of NOS asbestos brakeshoes for the front brakes, so maybe it would be wise to try that first...
At the moment the car pulls to the right a little on light brake application - on harder stops it tend to be more straight. The brakes has not been pulled while i had the car, and i am going to pull it apart and check it before driving 1500-2000 miles on holiday (with caravan). Maybe they will work better after a rebuild.

I've also found these guys online but haven't researched their product much yet. Might be worth a shot....

http://www.scarebird.com/12802/21632.html

Unfortunatly he clearly states that it does not work with 14" standard rims...

http://cgi.ebay.com/ebaymotors/Pontiac-Catalina-Bonneville-Chieftain-front-disc-brakes_W0QQcmdZViewItemQQcategoryZ33564QQihZ012QQitemZ220247500661QQrdZ1QQsspagenameZWDVW

This design seems as compact as it gets, so its properbly a case of bad breakes or unoriginal rims.. .

I'm going to email the guy with the full kit and see if he says 14" rims will fit. I'm pretty sure I've emailed him before. 14" rims are small and probably hard to fit decent sized discs behind them.

Ok here was his very quick reply.


hello,

i wish i could say yes. but they won,t fit a 14" will you need a 15" or bigger. to big of a car for such a little rotor to fit under a 14" rotor. and no cooling either. the rotors would warp very easy

thanks

greg



I agree with him. That would be a very small rotor to fit 14" rims.

Just make sure you have a good master cylinder and no leaks throughout the system and plenty of meat on your shoes and make sure it's all adjusted right and you should have a decent stopping old car.

i wish i could say yes on a 14" wheel. but they won,t fit a 14" wheel. you need a 15" or bigger. too big of a car for such a little rotor to fit under that 14" wheel. and no cooling either. the rotors would warp very easy. Greg Owner of Direct Fit Brakes. we do also have a toll free # 1-877-487-5330 and we do carry disc kits for about all older cars.

thanks

greg

Thank you Greg!

we have to save these old cars. if not disc brakes at least make sure your brakes are adjusted right and stay adjusted. also convert from a single bowl master cyl to dual bowl master will make your brakes alot safer and easier to stop
greg

That is a good point, you say your kit comes with a dual chamber master cylinder right? And it's a direct fit? Is that a GM part or is it yalls part?

yes we use the dual bowl master. yes it is a direct bolt on kit. and yes it uses GM parts. so replacement parts at any local auto parts store.
Greg

OK, after some thinking i think i have the master plans laid out...

Stage 1 :

First i rebuild the stock 11" brakes (2-1/2" wide front, 2" wide back, according to shop manual), then a upgrade to dual master with booster (my current single cylinder has no booster). I will e-mail DF-brakes for the right one. (i wwonder : Is the improvement only in the 2 champer redundancy and boost, or is the stoppingpower realy improved by changing to a dual champer ?)

Stage 2 : (some time in the future)

Get a set of 15" rims with matching whitewalls. I know a 15" rim from a 71 riviera fits, since i borrowed one until my new tires arrived.
Now it must be possible to fabricate an adaptor to fit the original hupcaps to the 15", saving the original 14" with tires for the rear weels - hope that it is not going to look too odd with 15" front/14" rear.
This should make room for the DF kit with minimal impact to the original look.

Wha do you think ? - is this a bad idea, or would it work ?. Any input welcome....

As far as I know there isn't a way to adapt 14" hubcaps to 15" rims. If you did it would look funny because there would be a little hubcap on a big rim.

Like I said before, My buick has stock power brakes and they work awesome. I'm converting my pontiac to stock power brakes. If tha is not good enough I will try a dual chamber to see if that helps.

Ok, you've got a point - maybe stage one is enough (i hope so) - i am going to start with rebuilding the stock brakes and see how it works...

That's what I'm going to do also.

I pulled the brakes yesterday, and they turned out to be in OK condition, nut in need of adjustment and cleaning. There were also a stuck piston in the right wheel cylinder, that is now fixed.
This made a great improvement overall, and i think i am going to leave it this way for now..

Good news! Probably save you a bunch of money and you can still use stock wheels.

Well I was bored as hell so i spent a few hours online researching brakes, and i have found some good news but I'm not too sure. I found on summit racing that the 59 Impala has a conversion kit out that will still fit the 14" wheels however i know the bolt patern is different, but here are my 2 delimas. 1. will 14in regular chevelle or any Chevy,GM disk brake rims hold my original hubcaps? 2. The kit comes with spindals, so the next question is, Do 59 Impala Spindals fit with our pontiac A-Arms and are the spindals the same in width, and height? If those work, you can convert those pontiacs to disk brakes......No mater what, i want Disks on my 59. If my other pontiacs didnt have the 8 lug drums on them i would be convering them as well....I hate the way the cars stop! As for stopping power i think they will be way better then the drums, not as good if you had 12in rotors and 15in wheels, but also they do make drilled and slotted rotors so you wil have the cooling it needs like a 12in rotor, But i know for a fact That the 11in rotors went on the 1970 Chevelle with a 450HP 454 and those cars stopped quite well, our Pontiacs are not as fast as that Chevelle and wont be treated like a race car. So as for stopping power I think they will work Fine, and a 59 Impala isnt a small car, and they wouldnt make brakes for a car if they didnt work properly.

59 Chevys and 59 Pontiacs use way different brake systems all together. Drop spindles and other suspension/steering/ brake parts will not interchange.

You can probably find a 14" wheel that will hold the stock hubcaps. I'd bet that a '59 Chevy uses the same bolt pattern as our cars do. They are full size cars also. Only when A bodies came out did they change them to the smaller 4.5"

I actually read somewhere that in theory drum brakes work better. The problem is the heat. They don't cool off like disc brakes do so you get some fade. A brand new set of drums and tuned right will stop great. You can always switch over to better boosters and MC and even use oversized WC for more stopping power.

in what way are the spindles different? is it where the tie rod hooks up to different? the more inforamtion i can find will help get this ball rolling since i really want disks on my car. i also have heard about drums stopping better, but as for cooling how can you cool drums off that fast unless you have 20's on your car then i can see air moving around that drum. Also if drum brakes were so good at stopping how come they dont put those all around on cars now, with technology these days im sure they can find a way to keep them cool. Any Ideas?

starchief_59 wrote:

59 Chevys and 59 Pontiacs use way different brake systems all together. Drop spindles and other suspension/steering/ brake parts will not interchange.

You can probably find a 14" wheel that will hold the stock hubcaps. I'd bet that a '59 Chevy uses the same bolt pattern as our cars do. They are full size cars also. Only when A bodies came out did they change them to the smaller 4.5"

I actually read somewhere that in theory drum brakes work better. The problem is the heat. They don't cool off like disc brakes do so you get some fade. A brand new set of drums and tuned right will stop great. You can always switch over to better boosters and MC and even use oversized WC for more stopping power.

I don't know about that Robert as my mom's '59 Biscayne has CAMARO rally wheels (5x4.75) on it. Are the Ponchos 5x5 or 5x4.75?

My grandfather designed the drum brakes on these cars. He also invented the self adjusting drum brakes.

He HATED disc brakes and when he was asked to design the brakes for the 1965 Corvette, he came up with the little drum in the rotor hat just to piss off GM. He didn't expect them to go with it. Funny thing is that it's being used today.