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Saturday, June 28, 2008


A rather crazy flat tire story

It turns out the Civic had one surprise in it. I suspect it's the fault of the dealership that sold the car to the previous owner - the previous owner and I had speculated that the Civic may have been water damaged as it had new carpeting and a lot of interior shampooing done to it. But it's in good mechanical shape so I'm not worried about the water damage and it looks to have been professionally repaired for the most part. Except this.

I had a flat tire on the way home from work yesterday. That would normally have been pretty routine, but when I pulled over I found out that the Civic's jack was missing. The tire iron was there although badly rusted like it had been sitting underwater. So I called my wife and asked if she could bring the floor jack. A helpful couple pulled over in a Bronco to help, but they had a truck jack that couldn't go under the Honda.

Once my wife arrived, I got the flat tire off, only to find out that the spare tire was on a five lug wheel and the Honda's wheels are four lug. Looks like a dealer had the spare tire either go missing or get badly rusted, and grabbed a random spare tire to cover things up.


Thursday, June 26, 2008


I know some of my readers aren't going to like this...

But when I picked out a replacement for the Corvette, I ended up chosing a '95 Honda Civic. I got a low mileage one at a price I couldn't pass up. This car's the right tool for the job, when the job is getting me to work 40 miles and back.

Will this Civic end up modified? You've probably noticed my daily drivers usually don't have mods on them, but I may have to do something to compensate for the shock of going from a Corvette to a Civic. The first area I hit may be, believe it or not, the suspension. Sure, it's lighter than a Corvette and in some ways seems to react more quickly. But it also feels mushy and has a huge amount of body roll compared to the Corvette. Perhaps some good shocks and sway bars will clean that up.

Sometime down the line, I may need to do something about the drawback it has that Civics are so noted for, not making any torque. But on a Civic, torque's a lot more expensive than handling...


Tuesday, June 24, 2008


A send-off for the Corvette

I sold the Corvette today. As it turns out, posting a Corvette on Craigslist at a low price can get some unusual offers - I had people wanting to trade a couple unusual things for it, from a Geo Storm (and cash) to a lifted Range Rover to an unspecified motorcycle. But today I had two Swedes drive down from South Carolina to meet me at work and pick the Corvette up there. They bought it and will be sending it on to Sweden.

To the buyers who bought it, happy trails and low taxes to you.


Saturday, June 21, 2008


The plug-in hydrogen hybrid, part 4

I was pretty sure locating a hydrogen generator on the car would be a bad idea, even if you powered it with battery packs instead of trying to drive it from the car's electrical system (after all, an alternator that demands 50 hp is going to put a big dent in your gas mileage). But I wanted to find out just how bad an idea it was, whether it was something that you could build but would be inadvisable, or some sort of monstrosity that wouldn't be able to move under its own power. When I calculated what size battery pack the hydrogen generator would need, it came out as something that looks like it would be technically possible but definitely not practical. Because an internal combustion engine isn't as efficient as an electric motor, this thing would have worse battery issues than an electric car.

The problem is that you're trying to plug it in before the hydrogen generator instead of after. Put the hydrogen generator in your basement and you might have something. So here's a few calculations to find out what it is you might have.

Gasoline has an energy density of 34.8 MJ/liter, according to Wikipedia. Some math turns that into 132 MJ/gallon, to 36.6 kilowatt-hours per gallon. So if you were making the hydrogen at home from household current, your cost for the equivalent of a gallon of gasoline would work out to this:

Price of a "gas gallon equivalent" = (Cost per kilowatt-hour) * (36.6 kilowatt-hours per gallon)/(Generator Efficiency)

Don't forget to factor in the energy needed to compress the hydrogen into the generator efficiency. You'd want to generate the hydrogen and oxygen separately, since you'll need to compress it in order to carry enough hydrogen to make a difference. So if you're paying 12 cents per kilowatt-hour and your generator's total efficiency is 50% including the power needed to run the compressor, you'd be paying the equivalent of $8.78 for a gallon. By the way, you'd also be stuck with similar costs on the plug-in hydrogen hybrid, although your generator efficiency would be up because you wouldn't need to compress the hydrogen nearly as much.

Still not good, but bring the price of gas up and the efficiency up and you might have something...

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Friday, June 20, 2008


The plug-in hydrogen hybrid, part 3

When I last blogged about the idea of a "plug in hydrogen hybrid" that had an onboard hydrogen generator powered by plug in batteries, things looked a bit crazy. The SUV needed 36.7 kilowatts to drive its hydrogen generator, and that assumes that it's a 100% efficient generator. I'd translated that to 2500 amps if the generator ran at 12 volts. In practice, it probably wouldn't - you'd use a higher input voltage and less current. But this figure helps because batteries are rated in amp-hours. Although these are over a 20 hour discharge period, we'll assume it can deliver the same number of amp-hours in a single hour. We need a total of 2500 amp-hours of battery.

Since these batteries are going to be drawn down very low and recharged, a good starting point might be to see what we'd need if we were buying Optima deep cycle batteries. From that chart, we see the D31A model puts out 75 amp hours. So we'd need 34 such batteries to run our generator for an hour. And 34 of these would cost $7818.30, and weigh 2033.2 pounds. Quite a lot of batteries to lug around.

Well, maybe our initial assumption, an SUV that got 20 miles to the gallon at a steady 60 mph, was a bit unrealistic. What if you have an economy car that got 50 mpg at the same speed? That's easy, multiply the number of amp hours you need by 0.4 and repeat the math. You come up with 1000 amp hours, 14 batteries, 837.2 pounds, and a tab of $3219.30.

And those assume that you're trying to get 50% better mileage with a 100% efficient generator, for just one hour. Realistically, you're not going to get a 100% efficient system. There's a good chance you may need a battery pack 50% to twice as heavy. Carrying around a a ton of batteries (literally) is going to drag that mileage back down, to say nothing for what it does to your acceleration.

At this point, it looks like the idea of a plug-in hydrogen hybrid can't be saved. Or can it? Here's a hint: This example is plugged in the wrong way.

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Sunday, June 15, 2008


That's one fast Cavalier! (Well, not really.)

I took a test drive in a 2005 Chevy Cavalier this weekend, wondering if it would make a decent commuter car. Well, I can say the one I test drove definitely wouldn't without some work. I cranked it up and things were OK, right up until I looked at the speedometer and it said I was going 65 mph. It didn't feel that way, but I lifted off the gas a little... and the speedometer didn't slow down at all. So I pulled over and brought it to a dead stop, and the speedometer read 55. Next time I stopped it was at 75. By the time I got back to the dealer, the speedometer had gone past the 110 mark (the highest reading on the dial) and nearly made it 360 degrees around back to zero. I decided to pass this car up, even though this might have made the perfect excuse if I got pulled over for speeding.


Sunday, June 08, 2008


Just wanted to share this comic strip...

Found this in the paper yesterday - Mallard Fillmore takes a pot shot at people who expect Washington to solve gas prices, and the politicians who encourage them. Given that Washington let the Pentagon pay $600 for a toilet seat, it's hard to expect politicians to succeed with dealing with $4 a gallon gas. Expecting government to fix the problem is an even worse to try saving at the pump than putting magnets on your fuel line.
View it at the Seattle Post-Intelligencer.


Sad decision - putting the Corvette up for sale

Today I finished a round of electrical repairs on the Corvette. It started when the alternator and a fusable link failed while AutoFab was putting on a new smog pump (as I didn't want to spend my own time dealing with the car). Well, the cooling fan failed on the way home. So I tore into the wiring myself. Ended up replacing the fan motor, another fusable link, the positive battery terminal, and the battery itself. After confirming every one of the parts I replaced had, in fact, gone bad. Seems like it had some sort of mini electrical meltdown. But it's running now. Because I want the next owner to start with something they can confirm is, for the most part, in sound and operational condition.

I've decided to put the Corvette up for sale. I know it's the sort of car where 10 years from now, maybe 20, I'll find myself wishing I still owned it. But this car should be someone's project and weekend driver, not the car I depend on to get me to work. It's still got a few nagging electrical gremlins, including an A/C blower that only works when it feels like it and wipers that don't always turn off when they should. It gets 19 miles to the gallon in the city. And, I've got to face it... I'm not a very good racing driver, and a Z51 is not a very forgiving car to take around an autocross. It's the wrong car for me right now, and I know that I need to sell it.

But even with its foibles, I can't say I regret having bought the Corvette. It's a chapter in my life story written in iron and fiberglass:

I'll be able to tell people for years about how I owned a Corvette once.

I'll be able to tell them about the time it got me safely through a blizzard on the way home when SUVs were taking shelter in the nearest parking lot.

I'll be able to tell about the time I took it drag racing.

I'll be able to tell about how much fun it can be to cruise with the targa top off.

I'll be able to tell about the time I got it sideways repeatedly in a Six Flags parking lot. (In an officially sanctioned race, that is.)

I'll be able to tell about the funny looks I got using the Corvette to haul garbage to the dump because it could carry a trash can better than my wife's sedan.

And I'll be able to tell how it wasn't too much of a financial hardship to sell it, because I can honestly tell about how I was able to buy a Corvette with an envelope of cash.

Whew. Quite a memory. Now, anybody wanting to buy a C4 Corvette? I'm only asking $4,000 and I'm flexible on the price. It hasn't been abused all that much.


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