'63 vs. '64-5 Riviera braking system differences

[Rivdrivn]

So, why does '63 require an auxiliary vacuum reservoir on the driver-side inner fender and the others don't?

[Jim Cannon]

The external vacuum can on a '63 is your reserve vacuum.  On the later power brake boosters, they figured out how to keep a stored reserved volume of vacuum in the booster housing itself, to give you a couple of power assisted braking actions after the engine stalls or dies for any reason.  After you use that reserve of vacuum up, let me tell you, it's like trying to stop a tank by dragging your feet!  No fun!

[lrlforfun]

OK Riviera People: I recently purchased a brake like kit from Classic Tube. They list. 63 different than 64 and 65. Any body know about the differences?   Mitch

[KongaMan]

Hard sayin'.  Inline lists the same kit for all three years.

Edited December 6, 2017 by KongaMan (see edit history)

[jimtash]

5 hours ago, KongaMan said:

Hard sayin'.  Inline lists the same kit for all three years.

 

That's the kit I'm currently using. I've only managed to install the front lines so far and it's going pretty good. The front left line is slightly too long so I just gave it a slight bend to take out the slack. And in order to clear the right suspension, I had to straighten the end of the line and then bend it back around the shock tower. The engine has headers so clearance is tight. I tightened the line down by working back to front using the frame to make the final bends. The center strap was the last to get tightened.

 

Car has a dual master cylinder conversion using a '67 Chevy II MC. It was not done by me. The front lines use the stock distribution block and a line coming from the rear reservoir of the MC. The rear is tied directly into the front reservoir via a custom line and fittings. They bypassed the distribution block completely. All the brake lines from what I can tell are the originals and unmodified. I'm still trying to figure out how they tied in the brake light switch. There isn't one on the hydraulic portion of the system.

Edited December 6, 2017 by jimtash (see edit history)

[jimtash]

6 hours ago, Jim Cannon said:

The external vacuum can on a '63 is your reserve vacuum.  On the later power brake boosters, they figured out how to keep a stored reserved volume of vacuum in the booster housing itself, to give you a couple of power assisted braking actions after the engine stalls or dies for any reason.  After you use that reserve of vacuum up, let me tell you, it's like trying to stop a tank by dragging your feet!  No fun!

 

Same thing as coming down a mountain and experiencing fade. No braking whatsoever. Zero pedal feedback. If I had to make a stop to avoid hitting the rear of another car, couldn't do it.

 

Driving a car with 4 wheel drums is a learning experience. Easily locked up in wet weather if the driver isn't careful, can quickly fade, and braking distances are long.

[Rivdrivn]

The reason I'm asking is I have very little power assist at lower rpm due to the big cam I am running. It's kinda scary navigating a parking lot. So, I'm thinking of adding the reservoir. By the way, the judges at BCA thought I was missing that piece, and pointed to the mounting spot on the inner fender. Lol 

[Seafoam65]

                       The reservoir is not going to help......the tank will just store the same crappy 10 inches of vacuum that your engine produces.......

it will not increase the vacuum to above 17 where it should be. The solution is either put a milder cam in the engine or install an auxiliary electric vacuum pump.

[Rivdrivn]

44 minutes ago, Seafoam65 said:

                       The reservoir is not going to help......the tank will just store the same crappy 10 inches of vacuum that your engine produces.......

it will not increase the vacuum to above 17 where it should be. The solution is either put a milder cam in the engine or install an auxiliary electric vacuum pump.

Thanks, Winston. I currently have 9 inches with a reservoir canister located next to tranny where the trunk release usually goes. I thought I'd remove it and put the pump there (Can't find any other place to put it). With the addition of a pump I thought some extra vacuum capacity would still be prudent, and why not use a stock item. Not sure if my 4-note horns will still fit, however.

[RivNut]

For big crammed engines which aren't producing the needed vacuum, look into installing a hydro-vac unit.  It uses the power steering pump to create vacuum.  My 1983 Riviera XX which had four wheel disk brakes, came from the factory with a hydro-vac system. Check out YouTube for some examples of retrofits.

[Rivdrivn]

3 hours ago, RivNut said:

For big crammed engines which aren't producing the needed vacuum, look into installing a hydro-vac unit.  It uses the power steering pump to create vacuum.  My 1983 Riviera XX which had four wheel disk brakes, came from the factory with a hydro-vac system. Check out YouTube for some examples of retrofits.

Thanks, Ed. I've been studying that possibility too but I prefer the stock look whenever feasible. While Black Bette is already highly modified, to the casual observer she doesn't look it. And I like it that way - a stealthy sleeper. That said, I do like the idea of hydroboost. Do we have any members who have actually tried it on a Riviera?

[65VerdeGS]

9 hours ago, jimtash said:

 

Same thing as coming down a mountain and experiencing fade. No braking whatsoever. Zero pedal feedback. If I had to make a stop to avoid hitting the rear of another car, couldn't do it.

 

Driving a car with 4 wheel drums is a learning experience. Easily locked up in wet weather if the driver isn't careful, can quickly fade, and braking distances are long.

 

Oh, yes, been there!

 

I was driving along I-5 south of Portland, Oregon a few years back when to my surprise I had no brakes!  I tried braking as the car in front of me had slowed down.  The pedal went clear to the floor!  I swerved into the (luckily) unoccupied left lane to avoid rear-ending the slow guy in front of me.  What to do?  I had zero, and I mean zero brakes.  Of course I needed to get safely off the freeway, but how would I do that?   I had two options - the transmission, and the parking brake.  Neither would stop me in any hurry, so it would be "white knuckle" time.  I let off the gas and spotted an exit ramp about 500 yards ahead.  As the car slowed I shifted into second, then first.  I navigated up the exit ramp onto suburban streets, all in first gear.  Then I managed to coast into a gas station a couple of blocks away, bringing the car to a halt using the parking brake.  I was lucky!   Turned out the rear brake line over the axle had developed a pin-hole leak, allowing all the brake fluid to gradually escape as I cruised down the freeway.  When I checked the single master cylinder reservoir it was dead empty.  I filled it up, and the brakes returned.  So i drove away, checking the brakes regularly.  I could go about 50 miles before losing sufficient braking action.  I got all the way home to Vancouver BC by re-filling the master cylinder.

 

I have other scary stories about this car for another day.

 

I must disagree with Jim about the merits of the stock Riviera 4-wheel drum brake system.  While not as good as modern disc-braked cars, the Buick aluminum front drum system was recognized as the best drum braking system on bigger American cars of the era.  Disc brakes became available in 1967, and only on the front axle (except Corvette, of course).  If properly set up these early Rivs stop straight and true.  Yes, repeated high speed stops can induce fade, but for normal driving, even in hills, the braking system is competent and not fear inducing. 

 

Now if you want to drive a scary braking car, try a 1968 Eldorado.  I had one of those for many years and dreaded having to stop it suddenly.  Even though this car had factory disc brakes front/drum rear, it did not inspire confidence.  The Riviera stops more predictably, within a shorter distance.  And, more importantly, the Riv does not have a propensity for the rear to swing out under severe braking, as the Cadillac did.  

 

[KongaMan]

Not really sure what the problem is with the performance of the stock brakes.  One might suggest that barring component failure, any serious inadequacies on a specific vehicle are the result of improper maintenance rather than inadequate design.

[CTX-SLPR]

7 hours ago, Rivdrivn said:

Thanks, Ed. I've been studying that possibility too but I prefer the stock look whenever feasible. While Black Bette is already highly modified, to the casual observer she doesn't look it. And I like it that way - a stealthy sleeper. That said, I do like the idea of hydroboost. Do we have any members who have actually tried it on a Riviera?

I have a hydroboost on my '64 Riviera.  I have to say that its not an easy conversion to do.  The way the original booster is mounted directly to the firewall requires you to either have a brake pushrod that is far too short to work well or you need to space the booster our 3.5in or so from the firewall.  The next problem is the Riviera brake pushrod is not a standard size and I ended up knocking the pin out of the pedal to use a Heim joint to keep the pushrod from binding like it did on my first attempt of using a standard drilled hole like the stock unit used which had bad binding problems.

 

One final thing is the Riviera has a really low pedal ratio compared to most other power brake cars so you end up with not a great pushrod travel which can make it sensitive to master cylinder bore diameter.  I'm still running stock drums all around on an 96 Impala SS 1 1/8in bore master and it will lock the brakes hard.  That being said, I did move the upper pedal pivot 3.5in down to improve the ratio so it's closer to most other GM power brake pedal setups.

 

 

[telriv]

Why do you think it's so hard to find good used aluminum drums today is because us roundy-rounders used them all up & all that we could find. They were the next best things to disc brakes & the un-sprung weight was less making the car handle better. Many preferred the Buick aluminum drums over disc brakes because of this. On a vehicle that many times weighed less than 2200 pds. we NEVER had a brake fade problem as they cooled off pretty quickly.

[jimtash]

On 12/6/2017 at 3:34 PM, 65VerdeGS said:

 

Oh, yes, been there!

 

I was driving along I-5 south of Portland, Oregon a few years back when to my surprise I had no brakes!  I tried braking as the car in front of me had slowed down.  The pedal went clear to the floor!  I swerved into the (luckily) unoccupied left lane to avoid rear-ending the slow guy in front of me.  What to do?  I had zero, and I mean zero brakes.  Of course I needed to get safely off the freeway, but how would I do that?   I had two options - the transmission, and the parking brake.  Neither would stop me in any hurry, so it would be "white knuckle" time.  I let off the gas and spotted an exit ramp about 500 yards ahead.  As the car slowed I shifted into second, then first.  I navigated up the exit ramp onto suburban streets, all in first gear.  Then I managed to coast into a gas station a couple of blocks away, bringing the car to a halt using the parking brake.  I was lucky!   Turned out the rear brake line over the axle had developed a pin-hole leak, allowing all the brake fluid to gradually escape as I cruised down the freeway.  When I checked the single master cylinder reservoir it was dead empty.  I filled it up, and the brakes returned.  So i drove away, checking the brakes regularly.  I could go about 50 miles before losing sufficient braking action.  I got all the way home to Vancouver BC by re-filling the master cylinder.

 

I have other scary stories about this car for another day.

 

I must disagree with Jim about the merits of the stock Riviera 4-wheel drum brake system.  While not as good as modern disc-braked cars, the Buick aluminum front drum system was recognized as the best drum braking system on bigger American cars of the era.  Disc brakes became available in 1967, and only on the front axle (except Corvette, of course).  If properly set up these early Rivs stop straight and true.  Yes, repeated high speed stops can induce fade, but for normal driving, even in hills, the braking system is competent and not fear inducing. 

 

Now if you want to drive a scary braking car, try a 1968 Eldorado.  I had one of those for many years and dreaded having to stop it suddenly.  Even though this car had factory disc brakes front/drum rear, it did not inspire confidence.  The Riviera stops more predictably, within a shorter distance.  And, more importantly, the Riv does not have a propensity for the rear to swing out under severe braking, as the Cadillac did.  

 

 

Got the car finished yesterday and it brakes fine for what it is. At least now they're not as sensitive as they once were and the force is even on all four wheels. No pulling to one side. One still has to learn to drive a 4 wheel drum car especially compared to modern braking systems. And checking the adjustment every so often is mandatory. It has a huge impact on pedal feel as well.

[Jim Cannon]

6 hours ago, jimtash said:

 

Got the car finished yesterday and it brakes fine for what it is. At least now they're not as sensitive as they once were and the force is even on all four wheels. No pulling to one side. One still has to learn to drive a 4 wheel drum car especially compared to modern braking systems. And checking the adjustment every so often is mandatory. It has a huge impact on pedal feel as well.

 

If they are all freed up and working properly, the Riviera has automatic brake adjusters on each wheel.  They are activated by applying the brakes rather firmly in reverse.  You can not over adjust them, so you can back down your driveway or a street and apply the brakes repeatedly to adjust them all out.  They will all be adjusted up correctly by doing that.

 

 

[KongaMan]

IMHO, while the Riviera certainly isn't a modern car, the braking system is far above the norm for that era.  It certainly isn't something that one has to be leery of when driving.

 

I would note that if you don't get the adjustment close after you button everything up, it can take a while for the adjusters to dial it in.  There are about 30 teeth on the adjusting wheel, and each application of the brakes only moves the wheel a few teeth.  If the adjuster is in all the way at the start, it can take several complete turns to expand properly.  Do the math: that's a lot of backing up and braking.  Moral: adjust the brakes per the manual before you start driving it around.

 

If your brakes aren't adjusting, one thing you might look for is missing teeth on the wheel.  If there's nothing there for the arm to catch, nothing's going to move.  You also need to make sure that the adjusting screw turns easily.  The adjusting arm is spring loaded; if the force need to turn the wheel is greater than the force needed to compress the spring, the wheel won't turn.  Which also argues for making sure you have a strong spring on the arm.  Unfortunately, that spring is usually not included in a brake hardware kit, so most folks are running around with the original (and possibly weakened) spring.

[PWB]

Hoo wee,  some scary stuff.

 

Makes me glad to have dual reservoir - fin cooled -  booster Dewey on my '67!

 

No drama  

 

- Happy Golden Anniversary '67!

 

Edited December 9, 2017 by PWB (see edit history)

[RivNut]

No drama when they were new, no need to worry about them now.  As always, take care of them as if your life depends on it.  

[jsgun]

If you have a pick-a-part salvage yard near you, you can get a vacuum pump from a cadillac. I think early 80's models have them, but I don't remember the exact model. Eldorado?. I believe some diesel pickup trucks do too.