2008-01-18

The (not so) good old days.

One of the thing that I hear when I discuss modern cars with people who used to love cars is "All of the electronics on a car make it impossible to work on!".

Umm... No. And I have the perfect example.

Fuel injection is a beautiful thing. Do not let anyone tell you otherwise, because of the alternative: Carburetors.

To explain it simply, a carburetor is essentially a (or several) very precisely machined tube(s) on top of your engine, that allows vacuum to suck fuel out of a precisely machined hole in the side of said tube(s), that has a reservoir of gasoline inside of it. On top of the tubes, are precisely machined flaps that effectively control the size of the tube. These flaps are connected to your accelerator pedal.

More simply put, it's a very precisely CONTROLLED FUEL LEAK. That doesn't adjust for anything, except the amount of air flowing by the jet.

Yeah... that was great when we didn't have options. Things have evolved a tiny bit since then.

We now have the ability to tell how far your lead foot is mashing that pedal. A throttle position sensor does this simply.

We now have the ability to measure how much air is rushing into the engine when you do mash that pedal. Mass airflow sensors do this for us.

We now have the ability to tell how dense that air is. A simple intake air temperature or manifold air pressure sensor does this for us.

We now have the ability to tell at what point each cylinder of the engine is in, via crank and cam sensors.

With this plethora of information, we can deliver fuel to the cylinder right as it starts down on its intake stroke. In precisely the correct amount for the amount of air that is being drawn into the cylinder. A good thing.

Why in the hell would we want to go back to a controlled leak? Really? I mean, it *really* sucked when driving across country, when you got into significantly different elevations than where you usually drove the vehicle, because one of two things happened:

  • It belched black smoke when driving up the hill, because the carburetor was set up for the soup that people at sea level call air and delivered too much fuel.

  • It ran hot and started knocking because the carburetor was set up to to have an auxiliary O2 tank on top to deliver enough air to actually burn fuel, thus not delivering enough fuel.

Either way, the performance suffered when the elevation changed more than a couple of thousand feet.

Closer to home, fuel efficiency went way up when we switched to fuel injection. Along with more precise measurement (due to knowing how much to deliver for the amount of air) and timing (due to knowing where every cylinder is at any given time), we can now also more precisely place the fuel at the valve, instead of letting it puddle inside of the intake. Ford is currently working on a direct injection system that puts the fuel directly into the combustion chamber, making the placement even more precise.

Tools are available for those who do wish to spin their own wrench. The computer is very good about giving very detailed troubleshooting information as well, at least on the later model vehicles.

There are places where technology has killed the art of the car. Fuel delivery and other engine management is not one of them.

2008-01-11

THIS!! BUILD THIS!!!

The new Buick Rivera concept. Designed by GM's Shanghai division, it's not American design, but it's absolutely beautiful. Not an Aston Martin, but beautiful nonetheless. This could complete with the Mercedes and BMW midline offerings easily, if they could build it with good fit and finish, even if the gullwing doors don't make it to production.

GM, please... let this come to fruition, with as few changes as possible. It is doable. You could sell these and make a tidy profit off of them. Power it with the LS3 or LS7 motor with matching transmission, sell them for $80k, and make those of us who think that we can do better than we are proud.

2008-01-09

My take on American cars... like it means anything

I really wish the quality of the big three's products would rival those of the top tier Japanese manufacturers. It's not that we can't design solid, reliable, easily maintainable cars. Many of the light trucks that the big three make will turn 250000 miles without much more than an oil change or two. Thing is that up until recently, the engines have all been small block motors by their respective companies, which have been in production for 30+ years. GM's small block is nearly, if not over, 50 years old. Same for the transmissions.

That's great. All of the problems have been worked out. These drivetrains function nearly flawlessly. I have read that the GM 350/5.7 liter small block is getting all the power out of it that is possible without force feeding it.

Thing is, it's big. Huge. The smallest factory produced vehicle (That I know of. I've seen kits that put small block motors in some crazy vehicles. Mazda Miata for one.) that one of those is shoehorned into was the Monza, which made maintenance an absolute nightmare.

Why can't they take something like that, and lop one bank off of it? It'd still be big, don't get me wrong, 2.5 liters in 4 cylinders is quite a bit of displacement, but at least at that point you could put it in something econobox size, have a huge parts bin, and a reliable engine. Shure, it'd shake like hell, but that's the nature of a 4 cylinder engine. You could even put an overhead cam head or two on it to make it more efficient, and even put that assembly on the big brother. Best of both worlds.

But even if you went with that, you still have all of the other problems that come with the typical American car: Lousy fit and finish, cheap parts, and designs by bean counters. It just sucks. When you go up the food chain, it gets a little better, but I can get a Honda Fit for less than $16k. Which I would think probably has much better fit and finish wise than ANYTHING I can get from a US manufacturer in the same price range. Probably more fun to drive too.

Part of the problem is that the manufacturers have allowed themselves to be dictated to by the UAW. It is my understanding that a good portion of the profits that GM gets from each sale goes to prop up a very heavy pension and medical care load. Daimler-Benz just spun off Chrysler to a private equity firm because they couldn't pull a profit out of Chrysler after 10 years of hard work. Ford is said to have, and I quote, "bet the factory" on their new Edge station w-.. err.. "Crossover SUV". Pardon me while I chase my eyeballs down the hall.

Perhaps I have just had too many bad experiences with American cars and I'm jaded. Perhaps the quality of the American automobile has improved in 10 years. Perhaps the bean counters have let the engineers design good cars recently. I've been hoping for that to happen over the past 15 years, and have yet to see it happen.

My next car will most likely not carry an American nameplate, and that makes a part of me very sad. I like to think that no one touches US engineering prowess... and in some fields, this is completely true. Just not in the "Volkswagen" category.