bry593

My '68 442 Vert is pretty much original, numbers matching. I assume that changing to front disc brakes would harm resale?

442Harv

I would change them. Then, save all your old items, and if you sell i, they can with the car, easy to change back. The brake change is worth it, much safer.

oldcutlass

Have you ever had any issues driving with drum brakes? In all my driving experience, sum of around 45+ years, I have never encountered any myself. They are simple to work on, parts are still plentiful, and in normal driving situations work very well. Whether the change would ultimately harm resale, doubtful if you save all the old parts. Its your car to do as you wish, mine is just a personal opinion.

442Harv

One more thing, do you have power brakes? If so, that makes a big it a big deal. I bought my first Olds in 1968, a 4Sp 442. I had no money, so cheap as possible. I drove a car with no power brakes, and, then I decided to spend the $36 bucks, with was something I wasn't planning on doing. My son has a 68 W30 with no power brakes, and believe me, when you drive it, especially here in Cal, with lots of traffic, you want to leave lots of room

rcorrigan5

My '68 4-4-2 convertible has power drum brakes. I don't particularly care for them as they are really grabby, but I chose to keep them as that's the way it came originally, it's a sort of family heirloom as my parents bought it new, and I don't drive it that much. It takes a little adjusting on my part when I drive it because of the grabbiness (my '69 4-4-2 convertible has factory disc brakes in front and they are so much nicer!) but I get used to it.

Randy C.

bry593

It has power brakes, but they tend to pull and the stopping distance is far greater than the other cars on the road. I'm worried someone is going to jam on their brakes in front of me and the classic olds is going to wind up with a mouthful of Toyota....

therobski

Hey check these guys out :https://www.porterfield-brakes.com/ before you make any decisions. They can reline the originals with today's technology.

JohnnyBs68S

I used to feel the same way w/ my '68's power drums, not a very linear grab as a function of pedal travel, push about 1/2 way down and nothing, then all of a sudden they grab with authority. In city driving, they've always seemed to have sufficient stopping power, but I've had a few hard stops from 70 MPH that end with both feet on the pedal to bring it to a stop, kind of hair-raising. Would NOT want to make 2 panic stops from > 60 MPH in a short period of time, they have significant fade. However, over the years after driving other vehicles, I've gotten used to the non-linearity, that or some of that "grabbiness" has been removed or faded over various brake maintenance of shoes, hardware, wheel and master cylinders, lines and now more recently a new power booster. That or it just doesn't bother me that much. I have noticed that w/ the rear gear changed from 2.78 to 3.90 and a trans swap from a Jetaway to a 200-4R, the much higher torque multiplication in 1st gear requires more pedal pressure to hold the car still at a light while idling. I do plan on a front disk swap in the front in the not too distant future as I plan on doing some 1/4 mile racing when I get my engine rebuilt, don't need to end up in the sand at the end of the run-off.

matt69olds

Koda

The one thing my all power drum 67 442 does better than my disc in front power brake 72 Monte Carlo is stop. Yes, they are grabby as hell. You stop, with authority.

Fun71

My experience with front drums was on the Gulf Coast where it very often rained so hard there was a foot or more of water in the road and wet drums did not stop well at all. Front discs were much, much better in that wet environment.

joe_padavano

Unless the car is a 100% original, paint dab and chalk mark car, I'd put the disks on if you plan to drive it. Do it correctly with the 1968 four piston calipers and correct master cylinder. This is a reversible change anyway. Keep the original parts.

Weezer

This was an interesting thread. I now have a confirmation that it's not just my '64 Starfire, with power drums, that has such immediate brake grab. Even after 20 years of ownership, I still lock up the brakes from time to time because they are so touchy.

As far as being worried about someone stopping too quickly in front of me, this is a big concern any time I'm out. I maintain 3-4 times the normal following distance because of it.

rob1960

I converted my '68 to front disc. I first restored the original drum brakes,they worked fine, but I wanted something with better stopping power just in case!.I saved all the drum brake parts for the next owner. I used all the '68 correct "stuff" under the hood,dual bale master,correct hold off valve, etc. but I went with the '69 up single piston calipers. They are much cheaper & everyone has parts for them. Inline Tube & others have the brand new 4 piston calipers & correct rotors but I just couldn't justify the extra cost for a nice driver. Besides I took the liberty of adding a complete repop Oai kit along with the red fenderwells which wasn't available with a/c or power brakes except on the H/O.

bry593

Yeah that looks great! You went a long way to make it look right with the hold off valve instead of the usual combo valve. I think I want mine to look just like that. Where did you find the hold off valve? I assume the brake lines are just normal Right Stuff Detailing for a '68 with discs down to the distribution valve on the frame, or did you have to bend them up yourself? What about the hardline to hose bracket, can I still use the drum brake location to the '69 plus calipers? Any other tips?

Koda

Rob, quick side question, how does that OAI hose like fitting at the hood and AC compressor pinch point? It appears it is behind the compressor?

chip-powell

Personally, I've never had a problem with my drums. My '71 has four wheel drums and except for one time I've never had a problem with stopping. That might be because I grew up with drums and that I also do not take my Cutlass out in the rain. Yes, drums perform worse in the rain, we all know that. But also, people need to understand that when you are out cruising, you are driving a 50 year old car that weighs about 1000 pounds more than your other cars. Watch your stopping distances, and try not to drive like an idiot (we all struggle with that one) and you should have no problems.

By the way, that one time that I had a problem was coming home from a cruise and the diaphragm in my power steering booster blew. Luckily, I was only about 10 miles from home with very little traffic. Still that final 10 miles with almost no brakes was interesting.

oldcutlass

Its not that drum brakes perform badly when its raining. They perform badly after being submerged in water and you have to pump the brakes to dry them off as your driving.

Run to Rund

Any brakes perform better with premium linings. I use Abex linings from Ott's Friction supply with original size drum brakes on my 66. Stops fine from 119 mph in the quarter mile. I also have a set of Velvetouch and while they are great when hot, they won't hold the car well in the burnout box when cold.

rob1960

The brake lines were the "factory" upper kit (3 pcs) from Inline. They fit perfectly from the distribution block on the frame up to the master & valve. I did have to replace the hose frame brackets with the '69 up style(they're thicker where the hose clips in) I had to drill holes for the mounting bolts but they fit fine. Koda, I'm using an old Edelbrock O4B intake which raises the carb up over an inch. The extra height really helps the fit over the a/c compressor. I also "flattened" the hose a bit on the bottom, it doesn't hit the hood. The hot air pipe for the air cleaner fits ok also with the extra height from the intake.

Koda

Thank you. One could eat off that frame.

rob1960

Thanks Koda!! The car is just awesome underneath, it was never in salt like cars here in rustbelt Ohio. All it took was a cup style wire wheel on my angle-grinder to bring the frame back to shiny steel. It's not even pitted. When I first bought it back in '12 I was disappointed since it had some mechanical problems that the selling dealer misrepresented but once I started working on it & saw how clean it really was I was quite happy! The brake lines at the wheels even unscrewed when I did the disc conversion. I replaced all the body mounts this past summer & they all unbolted with out a problem.

68conv455

My 68 had power drums that I swapped out for front disc years ago. Just think, every car on the road will stop faster than you.
Increasing following distance is a good plan but what about that one time you're surprised. It will happen if you drive it often.
If your car is safer, you will likely use it more often and have a more enjoyable experience while doing so. Hopefully, you'll never need them in a panic situation.

bry593

I never expected this thread to generate so many replies. Thanks everyone for the great feedback!

I think I'll take Rob's approach and go '69 442. That should minimize confusion for future owners and look sorta stock.

• Right Stuff Detailing - Master, hold-off, front line kit and hose brackets = $250
• Speedway - Wheel Kit with forged steel spindles and all that other stuff = $250

As I understand, drum/drum A-bodies have larger rear drums than disc/drum cars. So after the conversion, should brake better than a stock 1972 Cutlass?

rob1960

The rear drums are the same,9 1/2 x 2 on all a-bodies regardless of what was on the front. If I remember correctly only the a-body wagons(Vistas, etc) had 9 1/2 x 2 1/2 at the rear. I've seen some guys use the 11x2 rears from the 73-77 a-bodies on the earlier cars.

bry593

11x2, I think that's what my '70 Chevy B-body has on the 12-bolt. It has 11.75" front rotors (same size as '70 Corvette) and with the large drums on back, stops just fine (4100lb). What size are A-body rotors?

Will 10 and 12 bolt Chevy backing plates bolt to the "O" axle? I thought these had different bolt patterns?

bry593

Pulled the trigger on a CPP wheel kit (spindles, rotors, calipers and brackets, backings). I would have gone with the Speedway kit, but it didn't include spindles for $250. The CPP kit was $375 (shipped) and includes forged steel spindles and correctly designed caliper brackets.

Also ordered parts unique to 1969 A-body (shooting for '69 442 brake system): disc master with bleeders, front hardline kit, pressure reducing valve and hose brackets. I'll reuse existing power booster and brake distribution block. I think it should turn out pretty decent.

I think the total cost was somewhere around the $550 range. Not bad in my opinion.

bry593

Received all the parts. The CPP kit looks decent. It is of course entirely Made in China, but the machine work looks good. The kit includes new Chinese spindle bearings and I think I will toss these in the trash. Bearings are something I don't screw around with. If one goes bad, it will destroy the spindle and possibly the rotor. Could even cause the whole wheel to fall off. I can get a new set of Timkens shipped for about $25 and that seems like good insurance.

Edit: HL Bearings makes the taperd rollers in the CPP kit. According to the internet, they are the largest mfr of tapered bearings in China. Of course, every Chinese mfr makes some ridiculous claim, but who knows, maybe these bearings are of fair quality?https://hlbearings.en.ecplaza.net/

Nah, I'm putting Timkens on my 442. I will however use the cheapo seals since this is just grease retention.

joe_padavano

Don't be surprised if the Timkens are also Chinesium.

Schurkey

If drums are grabby or you lock the wheels in normal driving...there's something wrong with them and you just haven't figured out what it is. Nobody would have put up with that when these cars were new.

Biggest difference between OEM drums and OEM front discs is that the discs didn't fade as bad. Stopping power ONCE was about the same perhaps a slight improvement for discs. Overall, too weak in both cases. Repeated stopping, or stopping from very high speed gave an advantage to the discs because the drums faded faster/easier.

bry593

According to the 1969 Oldsmobile 442 Info Kit:
1. Standard drum brakes: all brake shoes are 2.5" wide. Front and rear use same brake shoes. Master cylinder = 1.0" bore.
2. Optional disc brake: rear brake shoes are 2.0" wide. Master cylinder is 1.125" bore. Single piston caliper.

RockAuto also lists both 2.00 and 2.50 brake shoes. So, cars converted to discs wind up with a little more lining area. Eureka!

joe_padavano

I don't know where you got that, but it is not correct. Every single Olds A-body built from 1964-1972 came with 9.5 x 2.0 rear drums EXCEPT the Vista Cruiser, which had 9.5 x 2.5 rear drums. RockAuto is not a reliable source for part applications - just try to get the right motor mounts based on their listings!

bry593

I agree, GM may have wrote it down wrong: https://www.gmheritagecenter.com/doc...2_Info_Kit.pdf

joe_padavano

I assume you are talking about Page 19 from the AMA specs form? Sorry, but that's a typo.

From the 1969 Chassis Service Manual, page 5-45. Also, if you check the parts book, you'll see that every single 1969 A-body Olds uses the same P/N for the rear shoes except the Vista. The Product Information Manual (aka Assembly Manual) for 1969 also shows the same 2.0" rear brake assembly on every A-body except the Vista. I'd call that a preponderance of evidence.

Or, you can go measure the ones on your car. We'll wait.

bry593

That's good to hear, but I'd rather you hold your breath. I'll let you know when I've finished looking.