DISC -V- DRUM: CHANGE MY MIND? Please. I want to learn about them?

Ok Guys,   Here I am! Change My  Mind! Teach me!

I'm sure we'll all see that both systems work. The pros and cons to both, the where as, the why fors, etc... Let's talk about this in the orders they are posted. Save confusion on who is talking to who. Although I'm talking to everyone interested.

I'll start.

First. That 400 ton jumbo jet.
Think about what you are referring to? Think about what you just said? “400 TONS”? Drum brakes would be a bad choice here! The heavier the more it takes to stay in flight. This is definitely a given.

If you recall? Answer 3). I stated that, weight reduction was a benefit of disc brakes. This is why I asked, what was he going to do with the car?

As for Budd railways and other big vehicles? Like I again said, Some manufactures are figuring out how to make disc work on some of these and it's not to stop better. It doesn't really matter whether a train can stop with in ½ mile or ¾ miles went a sudden stop is demanded. Usually by then it's far to late? Wouldn't matter whether it had disc or drum brakes? It is to keep cost down. But, most use drum at this point, with external shoes applied to the track surface of the wheels. I guess I opened this can?

As waynep7122 stated, and this can apply to many applications for many types of vehicles and companies, not just trains. “They have to be able to swap in a standard wheel set anywhere in the country...  many newer passenger car trains have disc brakes...” Again, what did I say? This is saving money. Ok, Ok it's saving time too.

Yes, disc brakes do run a little cooler for multiple HARD stops. This is the Nascar theory again. I'm a car nut so I like to refer to this aspect of the purpose of keeping brakes cool. Even these have added cooler devices, to aid in cooling. Larger contact surfaces to dissipate heat, and add more friction. Added pistons to apply so called brake torque.

Your Statement;
“Any brakes that will "lock up" have enough torque to exceed the available "rolling friction" of the tires under the conditions present. (see http://www.gi.alaska.edu/ScienceForum/ASF8/843.html for a simple layperson's explanation of the physics involved)”
Mine;
Yes, Effective brake torque is key. But do not rule out contact area. The larger the contact area the more heat is dispersed over an area allowing better efficiency of the application, and stopping friction are increased by added area. (Norm 2009).

Your Statement;
Certainly there are some "big things" that take a long distance to stop, do not usually engage in repeated stops without a cool-down period, do not have concerns with unsprung weight, and seem to benefit from the self-servo action of a leading-trailing shoe drum brake system.

No automobile I'm aware of is within that subset of vehicles.
Mine;
Yes, you are right! All driven vehicles have unsprung weight? This is what killed the H-car (Think that was the right letter for it, or might have been X). Do you remember the Citation? Yes that one. Front wheel drive? All the wait was in the front. It was nothing to do with drum brakes. Engineers could not figure out that to make this work they had to set up the the brake system to work diagonally. To balance the unsprung weight. So the car went by the way side, because the ass end passed up the front end in hard braking. As soon as the rear end weight became “unsprung”? Many vehicles never made it to production because of this.

Both  disc and drum work! (Norm 2009).
Your Statement;
Thus, the repeatability of stops (achieved through dissipating excess heat) and torque modulation ability (applying maximum usable torque on the threshold of lock-up without fade) are the two largest factors in repeatably shortening stopping distances while maintaining vehicle control.
Mine;
I can not out perform ABS. No human can. They can try to duplicate it with the human foot, but which wheel and how long the brake is applied and/or released is key. This is called “modulation” ?
(Norm 2009)

Your statement;
Properly sized and engineered disc brakes excel at both in light vehicles. Drum brakes historically have not.
Mine;
I'm not too sure if I understand what you are saying here? If it is what I think? Engineers of light vehicles of today have no choice but to exell with the disc brakes. Drums can be drilled, backing plates can be vented, Etc... They just have no choice! I'll talk about this just a few graphs down, as to why? So as to not to repeat myself.
Drum brakes were the first to get ABS. In automotive applications. (Norm 2009). It came down to cost, ease of assembly on the line, and weight reduction. Therefore increased profits, higher fuel economy and less man hours. (Norm 2009)

Your Statement;
Here is another take on the topic. One should note that rear drum brakes were retained for years because of (a) cost (b) rear brakes do only a third or less of the stopping work on most light vehicles, and (c) the difficulty of meeting federal parking brake standards (some early disc-type parking brakes tended to partially release as they cooled during testing).
Mine;
Your very right! As I said, It mostly boils down to cost? Yes it can even prevent things from coming about. This is why rear disc brakes are not standard on all vehicles?
Now I will explain why the engineers have no choice but disc  brakes!
As for most front disc, They HAD to be added to the little cars of  the 70.s. To get the cars lighter and cheaper, they had to get the McPherson struts or and equivalent to work. Engineering on vehicles starts years, in some cases a decade before they actually go into production, If they do at all? This is why most new year models are just re badged and trimmed last years models. Yes to get the whole picture we have to talk McPherson struts. It will be explained.
McPherson struts could not handle the extra weight as the shock (strut) is now required to hold the weight of the vehicle and the inertia of turns. McPherson struts in the early days, were at the fine line of being crap and usable. Thus also prompted the NEED for the radial tire. Then it was the steel belted. Improvements to tire has come along way.  (Norm 2009)
Yes, some times to understand one system of a vehicle you should understand the systems that are directly related. And the suspension is directly related to the officiancy of the braking system. Believe it or not? Don't believe it? How about that unsprung weight you were talking about?
This is how it all pretty much went down. I lived the changes!!!
McPherson struts could not be sold here in the US for many, many years. People just would not except them. Auto companies didn't want to take the risk. Finally in the late 50's through the  early 70's they were looked at as a possible weight reduction to the little cars. They had one big draw back. The strut (shock) was now supposed to hold the car weight in turns. Not the springs, control arm bushings, ball joints, etc... any more. No more frame mounts. This meant the car was being held on the road during high inertia buy two shafts that were only about ¾ to 1” thick. Not very hardy A? (Norm 2009)
The second problem was ride. Now the whole car moved with the movement of the strut., because the shock (strut) is now attached directly to the body, not a frame.
Actually these systems almost made their way into the first Falcons, Comets, Novas, etc... This is why the shocks are mounted to shock towers, just like struts. But it came back to the inertia of turns and ride. So, upper and lower control arms were added for stability. Ball joints upper and lower were added for ride and to make the system work.
In the 70's, actually in the late 60's, the auto manufactures started looking at the struts again, because they were lighter.
Working with them. Still the ride was harsh.
Then some air was let out of the Bias Ply tires from the standard 28 PSI to about 24 PSI. Now the car rode smoother and softer. Still had one problem.
In the turn there was still tire roll with the bias ply.  If the air is reduced the in these tires they will ride the side wall in turns and the tread will not stay flat on the road. (=Bad, bad handling) There goes your area of contact with the tire and road, less friction to stop? Wouldn't you say?
This prompted more looks at the tire. Light bulb goes off??? If the tire had a STEEL BELT  in side to keep the tread flat on the road. The tire may not roll in turn with lower tire pressures. “HOLLY DEFLATED BASKET BALLS BATMAN”!!!! It worked. Better ride with the struts and cornering as well. Let's get into production ROBIN.
Until todays improvements and the real concern about fuel economy. The recommended tire pressure was settled on at about 26PSI, for cars with struts. The actual tire pressure put in a tire is always set by the vehicle manufacture. Not the tire company.
Remember!!! The PSI on the side of a tire is maximum. If you set the tires to this, as the air inside heats up the pressure will exceed this max PSI and stretch and weaken the side wall, can also pull the rubber loose from the Belt, thus a broken belt. Any one ever had this?????
(Radial tires were not a new concept then. They had already been used in Europe on big expensive cars, they were all about ride and elegance. Some smaller cars with struts had them too in the later early years.)
I know, I know!!! The Firestone/Explorer fiasco? The Head Goon at Firestone blamed the tires on under inflation? If your ass was in the grinder you will come up with something, even if it is bull? He's the head *** every one has to believe him?????
Listen? Look at the tire pressure on a Corvette. These ride like brick *** houses unless the tire pressure is set at about 22 to 24 PSI. I'm not saying this! Look at the tire pressure decal.
I know! But these are advanced high performance tires used on these. Even with the early development flaws this is also true in the early years of the Vet and Radial tires. Hell they may have been the first US made car to offer them, I'm not sure.
There were a couple of obstacles still. Most car buyers did not like too much change all at once. So they had to be weened in on steel belted radial tires. So these became an option on some vehicles in the late 60.s and early 70's. As did they with disc brakes. People liked the ride and radials are now the standard. Disc brakes worked fine, so they were offered option and were standard on McPherson strut vehicles. Hay!! A system is born. It's a bouncing baby strut. AHHH, Isn't it cute. So you see? Disc brakes became a standard out of necessity not being a better system. With work, they became cheaper lighter, and well, “THE TREND”
All that to get to this?
Normsride – If it ain't broke don't fix it, also known as Peckerhead.
Don't cross the Mackinaw, Just funning! (Norm 2009)
If you want we can discuss most any thing about he automobile? Here's one myth for another time and place.
Question, Why should I not set a good battery on concrete? I'm not really asking, I already know the answer. If your interested in stuff like this let's all talk. Onward ROBBIN.
Hi, 68scott385
Bout all I can say to you is POWER BRAKES! These came in drum form too. Actually, let me think? Oh, ya. At one time you could only get them on drum brakes
Ok, back to you and our discussion.
Your Statement waynep7122
“drum brakes are great...   but when they get hot the drums expand slightly pulling away from the shoes...   the drums... the heat is also captured inside the drums...  i have several cars and trucks that have 4 wheel drum brakes... but i would rather they had at least front disc brakes... “
My  Statement;
You are very right wayneep7122. Drum brakes do get hot because heat is trapped inside the drum. They do expand a little. Under normal driving conditions they work great. The drum brakes do have heat sinks? The shoes, the drum, the backing plate. Fined drums are a better added heat sink.
Disc brakes have their own draw backs. The heat sink area is smaller, the contact area is smaller, which gives less heat dissipation, though being in the open helps here. With disc if they get slightly hot, the rotors warp, crack, fade, calipers don't return, keeping the brake applied, etc... Watch the  torque on the lug nuts, Improper tightening will cause warpage. Do not run through a water puddle after a hard repeated brake, things tend to crack. Not the throw away solids though, these warpand are so thin to begin with most can't be resurfaced legally. The metallic brake pads? Now there is a marketing strategy  for ya.  Organic pads did not wear the rotors down fast enough so, let's add metal to the pad and sell more rotors. The organic pads cost about 4 bucks a set, that's both wheels. Today they may cost about 12 to 16 bucks depending on the application. If you can even find them for your application. If the pads wore and the rotor lived well, a front brake job may only about 12 to 16 bucks. Metallics can cost double or triple this, just for the pads, and the rotors, well? Money, money, money. Give up the money. “HOLLY HOLD UP BATMAN” ,“THE JOKER HAS TO BE BEHIND THIS ROBIN!!!
The water puddle doesn't do drums much better either.
Aluminum drums were very bad for this, and they warped easy. Expensive as hell! Replacing these with discs? Now that's a swap I can understand under any condition. Aluminum is a good heat sink, but it will lose much of it's return ability if heated and expanded too much, we call this warppage.
Your Statement;
“As for rear disc brakes....  i used to have a bunch of customers with 4 wheel disc brake cads... i had at least one a week up on the lift adjusting the rear brake calipers...   i actually made a tool so i could take the lever and cable off.. and ratchet the parking brake bolt to bring the caliper back into adjustment.. so when i was done.. the brake lever could only move 7/16 of in inch off its stop... anything more than that.. and the pedal would be low...”
Mine;
You are right! Some of these can be a pain in the ass. I like things simple. Life it's self can be complicated without simple things being made to be.

Your Statement;

I also love that some of the hybrids... use regenerative braking so well.. that the wear surface of the brake rotors rusts from never being used...   who need brakes... turn momentum into electricity ...
Mine;

Yes, things will change as they always do. Much of the stuff is cool, But cool doesn't always mean better. I just get annoyed at some of the TREADS today.
Yes I am a high tech person, but low tech works as well.  Lived both. If ya listen to people of today, one would think the automobile and other things were just invented. Example; Here's a little OLD high tech, but  low tech to todays standards. Chrysler made an Electronic Fuel Inject 392 Hemi way back in the late 50's. It was actually put into production. How new is the Idea? That's another story in it's self.

I'm just saying Treads do not warrant unneeded changes. Unless it is something an individual wants, needs or is really better for a particular application.

As for just one example of disc -v- drum, and keep in mind? I'm not saying one is better than the other. Every situation is different. But I can give many examples like this, with all the classic cars I cruise with, Hundreds in on given day. One is bound to see and learn things. Here is just one example and this happened to me personally.

I had an experience were I was glad I had drum brakes!!!!! Yes, drum!!!! Ok, ABS might have helped here too. But my 66 Plymouth Sport Fury didn't come with ABS. Every one talks about repeated braking and heat, brake fade, etc... (Don't Ride The Brakes) No, But everyone complains of these.
I drive in the Woodward Dream Cruise. I'm not sure where everyone lives, but if you ever need a low speed proving grounds this is it. Test your car for over heating? Test brake fade? Test Idle, Etc... Found none better in the Northern US.

Any way, after spending the day getting my drum brakes really, really hot I hit the freeway at about 75 miles an hour, just got on. 696 is actually the freeway. Another guy in a Monte Carlo is riding beside me. He's checking my ride, I'm checking his. Suddenly about a City block ahead of us three cars stopped, trying get through a barricade setup that was placed to direct traffic and keep them on the freeway. Two in my lane and one in his. He noticed it first because I just caught his wheels locking up. Turned saw the cars and locked mine up. One car made it through the barricade the one was still in my lane, The other was trying to get over in my lane. I thought. This is it!
I actually stopped with about two car lengths between me and the car in my lane. Man was that scary. Did the little cussing these people out thing. But the guy in the Monte, which started stopping way before I did clipped the car in his lane and still took about 30 feet to come to a complete stop. He just could not stop fast enough. Talked to him at the seen. His brakes were only about one month old, The complete system. Mine the brakes were about 2 years old even though I check them every 60 days. He had Power brakes, mine standard. He is one that is definitely not going with the trends any more. He said, “I can not believe you just stopped before me”. Even though he started to brake before me, he had disc brakes up front, his car is lighter than mine. And we were doing the same speed. Thank god I had drum brakes!!! My  car stayed in the lane and straight. This is all with those so called over heated brakes and frequent stops all day.

This is just one example of drum brakes. Being fare, I can give examples of disc being better in certain situations.


Here's something to keep in mind? Use your imaginations for a minute.

If an Archaeologist a million years from now, discovered two vehicles in a cave.

After  analyzing both, not understanding numbers here. Try to look at things possibly from their eyes.

Let's say, one is a 1965 Malibu and the other a 2012 Malibu, (Only we now this, they don't).

After anolizing both vehicles they may come to the conclusion that the 65 was the latest (newest).

(Think about all this in the simplest why?)

It might look as if we (now) discovered ways to simplify the automobile.
Most civilizations advances are to make life easier.
One would think we figured out how to make headlights work with less wiring and eliminate all the modules.
On might think we learned how to get the engine to burn fuel with out all the wiring, modules, and possessors.
One might think we learned how to lighten a vehicle, (as the 65 is lighter than the 2012).
It would probably confuse the hell out of them, thinking that we went from disc brakes to drum brakes.
One might think we, near the end of our time, found a way to make the newest car recyclable. (Plastic is for ever). We know the 65 will return to the dust almost 98% of it.
One might think *** Well, you get the picture? Latest is not always the better? So, might they?

Now teach me what you really know? Change my mind? I'm listening? Convince me that the money and time spent on this type of swap is really worth it, when my  old car could use many other things that will really improve it and/or make it better.
Like I said I was only giving the guy some facts to consider. I just hate to see people waste time and money based on what some one else thinks is in or out of trend.
Remember, Classics and muscle cars are one of the longest trends there is in the automotive world. Biuld them like you like them. Biuld them for you. No matter what it is, looks like, options, performance, etc... The oldies will always look good to spectators.

Normsride---If it ain't broke don't fix it, also known as Peckerhead.  

i dont have time to read all that i stay with drums in the back because they hold on the foot brake alittle better. dont no if that long post has that in there. it seems like you cant teach an old dog new tricks with you. but you seem really into cars which i like.  

norm you should check out back to the bricks in flint next year we are now behind only the dream cruise as the second largest car cruise in north america.this august it was 25,000+ cars 250,000+ spectators its a good time only an hour north of you. with the two malibus i think an advanced cvilization would notice all the computers and electronics on the newer car and how much more complicated its engine is than the 65.plus you know as well as me that our old cars have very few "creature comforts".still hve to hold your drink in your crotch,lol.  

Ok here is my short two cents.  Drum brakes usually provide more surface area for friction and they have very little to no drag when not applied.  Those are the only two benefits I can think of for them.  18-wheeler's use them for the third reason that they can be set up to automatically engage if there is a problem (via powerful spring).  How ever 18-wheeler driver's are trained to not use them excessively because they quickly heat up (remember extra friction area)and fad.  Water retention/entrapment is another issue as well. But for over the highway use they make sense from the low/no drag and the high ability to stop a heavy load, ONCE, maybe twice.  Disc brakes work well because they can remain cooler with better heat disappation and any reduction of friction area can be made up in extra hydraulic clamping force (larger pistons area than drum brakes). And larger rotor's not only have more surface area but have a greater lever angle for stopping.  But it's really the heat dissapation and abilitly to cast off water that make them superior in the application of repeated braking, and even easier than drum brakes to design in repeated hard braking with minimal degradation to performance.

As an example I work with 250 ton haul trucks, the net vehicle weight loaded is 500 tons.  Since they are not over the road, a great amount of their time is spent braking at intersections, at dumps, under shovel's, etc.  They use disc brakes because those brakes are best fitted for the repeated braking that the vehicles see in use.

So it's all in application, and for drum brakes to meet the stopping expectations of the user, you have to ask yourself, what is the use? One or two good hard braking or repeated hard braking?  That being said, if you can lock your wheels up with either type of brake, the "extra" friction area of the drum brakes becomes null against the disc's, and the only benefit is lower drag of the shoe's vs. the disc pads, and frankly that is splitting hairs on the right side of the decimal point that only a vehicle like an over the road trucker would see when racking up millions of miles.

Oh yeah one last thing on the heat dissapation.  Even though drum brakes have a greater surface area of friction, if you put enough energy/heat into them on that one braking event, they will fail as the drum will not dissapate the heat fast enough to be effective.  Such as why drum brakes will not work well on a car over 100mph, nor an over heavy 18-wheeler going 80mph, nor a 400 ton jet landing at 150mph.  The drum's will quickly over heat in such applications and fail even on the first use of the brake.  
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The Silver Buick- '77 Skylark coupe w/ a Fuel Injected Buick 455&TKO-600, '72 Centurion Conv't - 455w/TH400, '67 T-bird 4Dr (suicide) w/428&C6. Needing to replace a '69 Firebird 400.

http://www.bangshift.com/forum/index.php?topic=6189.0

Norm's post was epic.

In response, The Silver Buick (as usual) makes some excellent points.

While the ascendency of MacPherson/Chapman struts, radial tires, and disc brakes mostly took place over the same period of time, it overstates the historical record assert that "but for" the adoption of struts, disc brakes wouldn't have become the primary component for light vehicle braking systems.

As long as we're dealing in anecdotes (i.e. the drum brake Mopar vs. the disc brake Monte Carlo . . .) I once built a 1970 A-Body Pontiac with the stock-type, non-power assisted four wheel drums. (All the magazines said that was the "hot setup" for drag racing because of less weight and lower rotational drag)  

Because GM almost criminally undersized the Poncho's brakes and the fashion "back in the day" was installing huge "wide oval" bias belted tires on massive reversed-offset "mags" (plenty of unsprung weight) while adding that "California rake" with air shocks so that the big "meats" would fit, stopping that "Tiger" from speed was always an adventure.  With drag-style "front runners" it was almost impossible to stop at speed.  

Dropping the rake, dumping the "mags" and installing a wimpy set of cheap, rock-hard steel-belted radial tires on tiny 14x6 Rally II wheels (still too heavy but surprisingly lighter than the fender-scrapping L-60s (rear), G-60s (front) and "mags" that came off) dramatically improved the handling and even shortened the stopping distances (notwithstanding a narrower and longer contact patch).   But the drums still faded badly under modest use.  Moreover, the cheap radials lasted about twice as long as bias belted tires under "spirited" driving.

Then I bought a '69 G-Body. It was probably 700 pounds heavier than the A-body. But it had front discs. Nothing special, just the heavy cast-iron 11" Delco Moraines with chunky sliding single-piston calipers holding budget organic pads (about as chinzy a disc brake set-up as has ever been sold).  

There was no contest between the cars. The heavier disc-braked car would stop far shorter, required no "futzing" adjustments or special friction materials, and never faded in street driving.  Once I added radial tires, it got even better.

However, the G-body took a back seat in stopping power to the first four-wheel disc brake Mustang I bought in the mid-80s (an SVO). Most certainly, the drastically lower curb weight, reduced weight transfer (Konis and stiff springs), and the then-modern "Gatorback" radials were factors. But the swept area-to-weight ratio of the brakes on the 'Stang was a lot better. Stopping distances were shorter.  The non-ABS system was much easier to modulate for "threshold braking."

Now such dusty anecdotes don't prove much of anything.  However, they are a microcosm of the engineering testing which brought about the switch to discs in virtually all light vehicles (not just strut-equipped ones).

Even with automatic self-adjusters, drum brakes seldom compensate for wear as well as disc brakes.  And as a vehicle ages, problems with self-adjusters increase.  Disc brakes (excluding disc-type parking brakes) do not have any self-adjuster issues.

Moreover,there is an interesting heat effect. Drums expand as they get hotter. So do discs. But expansion of drums is counterproductive, slightly reducing the friction and system response times.  But the expansion of discs have the opposite effect.

Wear on disc brakes is also easier to monitor than with drum brakes.

Disc brakes tend to be easier to field service than drum brakes.

Disc brakes have no bag full of springs and levers that need to be replaced when the friction materials are renewed (although caliper sliders and pins should be addressed).

Disc brakes have fewer moving parts to break (as anyone who has "popped" a self-adjuster or experienced permanent wheel lock-up from hardware failure can tell you, this isn't a triffling concern)

There are no leading and trailing shoes to keep straight (I can't tell you how many times I've seen cars in the shop with two leading shoes or two trailing shoes on the same side) or how many times I've had to field complaints about "one lining is shorter than the other."

Disc brakes are sometimes easier to bleed than drums and never require laying on one's backside with an adjuster spoon fishing around blind in some little slot for a "star wheel."  

Disc brakes have fewer contact points that must be lubricated for proper operation and reduced noise.

While much of the "fad" for huge disc brakes is style-over-substance (a set of "dubs" and some "pizza-pan" monster Brembos or Alcons might even increase stopping distances over a properly-sized and well-excecuted stock system), instrumented empirical testing has proven time and again the superiority of properly-sized disc brakes.

Is it worth dumping factory drums for factory-style discs? My experience says yes, there are marginal benefits. If the drums are not optimized (e.g. not Pontiac 8-lugs with metallic linings and impeccable maintenance) or are too small for the application (as on nearly every compact and midsize Detroit car in the '60s), then the benefits are likely signficant.  

Are you going to die if you don't switch? Probably not. Just don't follow "modern" vehicles too closely . . . .  
*****
TURBO TED --Internationally known as the "John Force of the Yugo Racing Association."

Sergeant-at-Arms and immediate Past President of the SoAL Yugo Owners Group.

You know guys? It's all cool, and yes I will check out back to the bricks. Almost when this year but did other things.

I'm pretty much one of the new kids on the block here? and as a new kid. one has to demonstrate that he is nollegable and one of the guys, or noone will take him serious. I'm just trying show, I'm not just a back yarder, although there is nothing wrong with being?

I do have to make some responses though.

As for drum brakes not working over 100MPH? I raced way back when, My favorite was the old coupes or wagons, straight front axle-(Just because they looked cool) almost lived at the "DRW" Got vehicle well above 100 MPH, went through the trap at the end and still stopped to make the turn to come back the return road. NO high tech here?

I have to read more of your coments and input to answer more. I'LL BE BACK

(Norm2009)---ain't broke don't fix it!  

Thanks Ted, you also made many more detail points.

As for over 100mph, I didn't say "they will not work", I said "they will not work WELL" especially in comparison to disc brakes. And a 1/4 mile pass in a relatively light vehicle is ONE good hard stop then let the brakes cool down. And by today's standards, a 50's or 60's wagons are pretty light, maybe 4,500lbs, but probably below 4,000lbs, and at least they came with larger drums to absorb more heat.  
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The Silver Buick- '77 Skylark coupe w/ a Fuel Injected Buick 455&TKO-600, '72 Centurion Conv't - 455w/TH400, '67 T-bird 4Dr (suicide) w/428&C6. Needing to replace a '69 Firebird 400.

http://www.bangshift.com/forum/index.php?topic=6189.0

I will not argue that radial tires out perform bias? I run them on all my old car. I do keep a set of bias for th Falcon stored. This for concourse show only.

You are right? Struts really were not the compete reason for discs. It was the leading factor. Imports, not sold in this country where all ready using struts, disc and radials.  US automakers had been working with strut scenarios since the late 30's couldn't make them work. because Foreign inventors held the Patents on the key components. Then in the late 30's and early 40's all had to forgotten about due to the war. This is why you will not see 1943/44/45 US made cars for the public. Then when production started again they produced the same vehicles that had been just before the war. I took many years for the US manufactures to be able to concentrate on being innovative again. The roads were bad. A few new Highways had be built. But over all the roads had deteriorated. Struts were just not feasible at that time. Many people could only afford “recaps”. The automakers Here had directed their attention to STYLING. Thous the 50's. Money started rolling again, struts, disc and radials started to be looked at again. Thous the smaller car in the late 50's. Things had to be proved to the consumer, and yes discs were the first to be proved. They actually worked great, but were only offered on higher dollar cars, because of the cost of paying patent rights, they were expensive. I will leave it at this. We could get real deep and technical. But I don't think that Automotive politics is the point that is trying to be conveyed.

As far as serviceability goes you have not convinced be. Very few things today are very serviceable.

I'll give you the expand ability of disc.

OK. You ask this;        Is it worth dumping factory drums for factory-style discs? My experience says yes, there are marginal benefits. If the drums are not optimized (e.g. not Pontiac 8-lugs with metallic linings and impeccable maintenance) or are too small for the application (as on nearly every compact and midsize Detroit car in the '60s), then the benefits are likely signficant.  

I will have to agree with you on this. The problem to day is becoming availability, cost. One has to determine the application of the vehicle? What is is being used for? After market companies do no wear near the testing the Auto manufactures do? Bolt on factory YES. Aftermarket ???? Again what is the vehicle being used for. Show=keep the drum, Cruising=Keep the drums, Racing=Go with disc, Roundy-round=Go with all 4 disc. BIG pockets=All 4 disc.

As for people today and the way they drive= ADD 2 sets of any type to all 4 wheels.  

I do agree Silver buick. If I had a large vehicle. I definely would take disc.
and yes todays vehicle are alot heavier that the old. A new car, I would choose disc.  

drums for the rear and disc for the front.  
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If, And this is IF, I did go disc on an old car? The pontiacman is the advice I myself would follow. Sorta meets halfway. The change at the axles, where it would do the most good. That would be the biggest bang for my buck.  

i also would go disc on front and drums on the rear.  

and do check out back to the bricks. the hole week was crazy. this was a real cruise three days in a row, not a parking lot stop and go roll like dream cruise. just watch out for cops when flashing some smoke as i just got back from court fighting my three point 200 dollar careless driving ticket. they droped it down to one point 125 dollars. but thats how we do it in the birth place of gm-flint michigan. isnt that right p2?  

Sounds like the Bricks are what I'm checking out next season.
I love to cruise not park and idle.
I got to the point that I go to Woodward a few days before the actual cruise day, so I could still make both and cruise.
Got a ticket a couple of seasons back at Woodward for burnout. Didn't see the cop standing in the crowed. stepped out pointed and then pointed to the curb. The burnout was so good the interior filled, the crowed disapeared, Hell, the people in the crowed wanted to pay my fine. At that time it was just a ticket for $82 bucks, Hell, I put some money away for the next season. Enough to do quit a few burnouts. I had a blast. It was worth every penny. Now, I think they give points or impound. Haven't done it in a while. The Down River cruise they Impound! Ouch!!  

yeah you dont want that,impounds are no good who knows what they would do with a sweet ride. if you have the time do come it was a blast. the three days before the main event were the best cruising all day long for three days what else can you ask for....maybe a cold beer and good food