I Felt Sorry For These Two Guys

[GreaseMonkey]

I don't know the facts surrounding these two incidents, so I won't judge. Even so, I suspect that excessive speed and / or following too closely were involved.

I was coming home on the southbound 405 from Huntington beach when I came upon the aftermath of two mishaps, both within 10-15 minutes of each other. The first involved a current-generation Mustang convertible. From the back it looked really nice. Bright silver with a black top, tasteful black aftermarket wheels, and four chrome exhaust tips. It had paper dealer plates on it. The driver, a young college-looking fellow with a neatly trimmed beard, seemed to be going awfully slow- even for the right lane. When I pulled up next to him I saw why. The hood was folded into an upside down v-shape and he was struggling to see over it! The grille was gone, and the plastic front bumper cover was all gouged up. Strangely enough, both front fenders looked untouched.

The second was a ( formerly ) mint 1953/54 Chevy Bel Air two-door. Two-tone white over light blue with sidepipes, whitewalls, and chrome Astro Supreme rims. The hood was crimped and the grille bashed in. A guy was sitting in the driver's seat talking on his cell phone. The car still looked driveable but was munched pretty good. Everyone who's ever driven one of those old postwar American cars knows how awful the brakes were on those things. Why Detroit chose to saddle those huge lumbering behemoths with such lousy stoppers is beyond me- especially since the superiority of disc brakes was known even then.

I felt bad for those two guys. Having your ride get trashed is always a bummer, but when it's a fancy niche vehicle you just bought, or a lovingly restored classic, it's doubly painful.

[bhskittykatt]

There's a road south of here that people like to speed on. It's curvy and cut right out of the cliff, so you have a rockwall on one side and going off into the void on the other. The speed limit is actually 45mph already and people still speed, despite it being narrow and having nothing but blind curves.

I came up on road flares once, and as I came around the bend there was a current generation Mustang that looked normal in the back, but the front end looked almost completely gone. It looked like he'd missed a turn and plowed straight into the rock! The entire front half of the vehicle was just squished in and looked like hell. There was a state trooper directing traffic around the wreck. I don't know where the driver was (windows were too tinted and smashed to see inside and it was too dark outside), but if he survived he was definitely going to feel it in the morning.

[EricKei]

Why Detroit chose to saddle those huge lumbering behemoths with such lousy stoppers is beyond me- especially since the superiority of disc brakes was known even then.

I can only hazard a guess -- the lousy ones were probably cheaper, and the good ones may (or may not) have been offered as an expensive upgrade...?

[Chromatix]

European designs tended, for quite a long time, to use discs on the front and drums on the back wheels, on the theory that the better brakes needed to be on the front wheels. The survival of the drum brake in that form for so long is good evidence that it must have been significantly cheaper.

The concept of the drum brake always confused me, incidentally. It was, to anyone who was familiar with bicycle brakes, an obviously flawed design - bulky, complex due to various workarounds for fading and misalignment, and *still* tended to fade badly at speed. Perhaps it was cheaper, but I have trouble working out why.

I get the impression that, bodywork aside, American cars tended to use a lot of common parts - or at least were very modular. In that context, making four of something for each car could have been quite a lot cheaper than making two of one kind and two of another. With the automotive industry being far less tightly regulated than the railway and airline industries, cost undoubtedly prevailed over safety concerns.

One example of a potentially superior design would be the humble tread brake, used on railways worldwide from the very beginning until disc brakes took over there too. For automotive use, the "tread" would have to be the rim of a steel disc fitted for the purpose, rather than the tyre. I'm told that in the 1970s, BR was mass-producing cast-iron brake shoes at a cost of roughly £3 each, having conducted research to find the optimum composition for performance and lifetime. Tread brakes are still fitted to some trains, even high-performance ones, alongside disc brakes - for the simple reason that they tend to clean the tread, improving adhesion on a contaminated rail.

[cleorose]

We have a road near our inlaws like that. Its a small town highway. It has a curve at one point. But people speed along the road doing 80-90-100 miles per hour.

In fact there USED to be a house there. Except in five years he had some 7 cars plow through his living room. One of those cars was my husband's nephew who was doing 110 mph around the bend. Hit the curb, flipped the car and went right through the front room. His friend who was in the passenger seat was fine. Bruised ribs, cracked wrist. His nephew lost his life though. There would be another teenager to die on that same bend going into that guys house before he decided to sell his house and move. Last we heard it was tore down and the people who bought it, rebuilt it further back on the property line and put BIG boulders at that corner and some trees.

[mhkohne]

European designs tended, for quite a long time, to use discs on the front and drums on the back wheels, on the theory that the better brakes needed to be on the front wheels. The survival of the drum brake in that form for so long is good evidence that it must have been significantly cheaper.

The concept of the drum brake always confused me, incidentally. It was, to anyone who was familiar with bicycle brakes, an obviously flawed design - bulky, complex due to various workarounds for fading and misalignment, and *still* tended to fade badly at speed. Perhaps it was cheaper, but I have trouble working out why

I don't know, but I'd always assumed that drum brakes did better in the face of poor tolerances or bad maintenance, and that's why they were used for so long. I do know that in all the cars I've had, I've had to have disk brake rotors resurfaced on a regular basis, but I can't remember ever having had to do anything on the drums.

[Chromatix]

Any perceived maintenance advantage would be simply because they're under less stress. With discs on the front and drums on the rear, nearly all of the high-speed braking energy will be absorbed by the discs and calipers, while the drum expands through heating and pulls itself away from the drum brake pads. The drum brake pads are also larger, so the wear they do receive is spread out more.

But when you have drums all around, you have to apply more pressure in the brake system to achieve acceptable deceleration, due to the fading caused by the aforementioned thermal expansion. All of the energy is absorbed by drum brakes, rather than most of it by discs. You're therefore going to have to maintain them much more.

[bhskittykatt]

We have a road near our inlaws like that. Its a small town highway. It has a curve at one point. But people speed along the road doing 80-90-100 miles per hour.

On the road I mentioned earlier, just yesterday a six year old boy died in a rollover crash when the car missed a turn and went off the edge (pic may be disturbing for some). And while it doesn't mention excessive speed, I'd put money on that being a factor.

But when you have drums all around, you have to apply more pressure in the brake system to achieve acceptable deceleration, due to the fading caused by the aforementioned thermal expansion. All of the energy is absorbed by drum brakes, rather than most of it by discs. You're therefore going to have to maintain them much more.

Good to know. My new (used) car has drums all around, which is not something I'm used to (old car was discs in the front, drums in the back, and I almost never had to worry about the drums in the back). I had to drive down a narrow, bumpy, steep mountain road yesterday, and by the time I reached the bottom they were of course very very hot...

[Chromatix]

The fact that drum brakes fade when they get hot is also why engine braking is a really good idea if it's available - and that's one of several good arguments for manual transmissions.

It's *possible* that certain automatic transmissions have that feature as well - try selecting the "1" or "2" settings instead of "D" when going downhill; if you engine then seems to start revving on its own, it's doing the right thing. It won't replace your actual brakes, but it'll help.

[bhskittykatt]

The fact that drum brakes fade when they get hot is also why engine braking is a really good idea if it's available - and that's one of several good arguments for manual transmissions.

I have a manual transmission and engine brake when I can. This particular mountain road was steep and muddy and rocky and bumpy and was a fairly loose definition of "road". But on paved surfaces I can do it a lot easier. Coming down a nearby mountain highway, you can definitely smell everyone's brakes, and I'm a little proud of the fact that mine are significantly less stinky when I reach the bottom.