Well, it was time for me to get some new tires. With gas prices being the way they are, I figured I’d try something to increase my fuel mileage. What I ended up doing was getting a tire that was slightly thinner, and slightly taller than the stock tires on my car. For those unfamiliar with tires a tire size usually looks something like this:

The first number, ‘235′, is the width of the tire in millimeters. The bigger the number, the wider the tire. The second number, ‘40′, is the sidewall aspect ratio. The height of the sidewall is the sidewall aspect ratio multiplied by the width. In this case, the height of the sidewall would be 0.40*235 = 94mm.

Okay, so, I got it in my head that a taller, thinner tire might help my gas mileage. Since I needed new tires anyways, I went and got a set of 225/45 tires to replace my original 235/40 size. That means my new tires were 4.3% thinner, and 1.6% taller. What was the result? About a 9% increase in average fuel mileage from 22mpg to 24mpg.

Now before you all go out and buy new tires, let’s talk about this a bit. There are a large number of factors that could have contributed to this increase in fuel mileage, and to be honest, I don’t know which one is driving the increase.

• Tire Pressure: being somewhat of a car nut, I’m pretty anal about my tire pressures. if you don’t already own one, go and buy yourself a half way decent tire gauge, and keep tabs on your tire pressure. Under inflated tires will eat gas. Anyhow, I kept my tires at 40psi before these tires, and they are at 40psi now. So I think that I can rule out a change in tire pressure being the cause
• Tire weight/inertia: having a lighter tire means that your engine will need to spend less energy getting your wheels to rotate, and consequently less gas getting from point A to point B. In this case, my mileage actually should have suffered slightly, as the old tires were worn out and weigh less than when they were new. But then again, the new tires were thinner. So all in all, it was probably a wash in terms of the weight change from the old tires to the new ones.
• Rolling resistance of the tire: okay, this one is a bit complicated, and I don’t really understand it myself fully. As far as I can gather, rolling resistance is mainly a function of tire pressure and tire width. The higher the pressure, the less the tire deforms and the less rolling resistance the tire has (that’s why you see some road bicycles running like 200 psi tires these days). Similarly, the wider the tire, the less the tire deforms, and the less rolling resistance the tire has. Given what i said in point 1, this means that with these assumptions, my wider tires should have had less rolling resistance. But I’ll be the first to admit that I think there’s something else going on here that I don’t fully have my head around. The compound of rubber will make a tremendous difference. My previoius tires were very high performance tires (Toyo Proxes TS-1), which means they had very sticky rubber. My new tires are less performance oriented (Kumho SPT) and consequently have harder rubber. I think that this may be the main factor in my increase in mileage.
• Gearing: as you may or may not know, between your car’s engine and the wheels there is a set of gears that transmits the power. Shorter gears allow you to accelerate faster, and taller gears allow you to cruise at higher speeds. Taller gears also result in better gas mileage because it allows the engine to run at a lower RPM which will have less losses to the friction inside the engine. Well, there’s one final gearing, and that’s the one between the drive shaft going to the wheel (the axle, or half-shaft) and the road. The taller the road is, the taller your final gearing ends up being. So in this case, by getting a taller tire, I have made my final gearing taller as well. This results in better mileage.

And there you have it, more info than you wanted to know about me trying to figure out why I got better mileage. At the end of the day, I’m surprised at how much better mileage I get (9% is a lot). I may not totally understand it, but the facts don’t lie. I’m getting better mileage, plain and simple. So if you’re in the market for new tires (if you have good tires, it’s not worth it to replace them), and could use a boost in mileage, give this prescription a shot:

1. Get a harder tire: All tires come with a Treadwear gauge. Now these aren’t the most accurate and consistent ratings in the world, but look up your old tires and find their UTQG Treadwear Grade. When you get your new tires, look for a tire that has a significantly higher treadwear, and it will end up being made of a harder compound of rubber.
2. Get a thinner tire: Don’t go nuts. I’d suggest deviating from your stock tire size by no more than 10mm
3. Get a taller tire: Again, no need to go crazy here. As I said, my tires only ended up being 1.9% taller. It takes a bit more math to figure out what sidewall aspect ratio you’ll want given the new tire width, but it’s not rocket science. You really don’t want to go too tall, because you might end up rubbing the tire on something in the wheel well.

Whatever you guys out there do, you do at your own risk. I take no responsibility for any misfortune you might come across for trying this out. Always consult your mechanic before doing anything to your car.

And now for quite possibly the most literal use of this acronym on the internet: YMMV!

[image source: Tirerack.com]

Filed under: Cars | Transportation — Santi @ 7:32 am

I like backpacks, but I usually travel light. I had been using a bulky North Face number (the Recon), which was a great bag despite it’s habit of getting snagged on things, until I saw this minimalist bag from Built NY. Fashioned from neoprene, it’s nicely cushioned and stretches to accomodate more stuff. While a lone laptop fits in it quite snugly, the fabric will stretch to accomodate a large pile of stuff if you want - and it’ll shrink back down afterwards. There’s actually two main compartments: a top-loading slot for laptops and books, and a side loading slot for the accessories; the two are separated keep things organized but otherwise the same size. There’s also a little pocket in the left strap for phones, keys, etc. I’ve got one, and I love it - the thing is comfortable as hell, and it gets great reactions - mostly people ask if it’s body armor! If that’s the look you’re going for, you can flip it around to the front and people will stare. Actually, the last time I did that someone told me I looked like Jack Bauer.

The Built Laptop Bag runs about $80 from their website, but Amazon is selling them for $60 right now. Be aware that they are not adjustable, and thus there exists a large version for the titans among us. Color options are black, olive, and a wood-grain type pattern in black and grey. Go grab one before Amazon bumps up the price!

Filed under: Other — Max @ 2:36 pm

Since I learned about the Pacific Trash Vortex I’ve drastically cut down on my bottled water consumption. Instead, I treated myself to this handsome metal bottle from Sigg that nestles into a stainless steel cup, and I’ve really been loving it. It’s oval shaped, so it’s a bit more pocket-friendly than a conventional bottle, and the black powder-coating is actually matte, which makes it look pretty badass. The cup and strap are totally removable, leaving you with a plain old Sigg Oval Bottle if you prefer that. Mostly I use the bottle alone, but I’ve been using the cup at home a lot. I keep getting asked if it’s a flask, actually - and it could be, because Sigg lines their bottles with a special coating to make sure that nothing from the metal gets into your beverage. (Acidic beverages, like lemon juice, will slowly dissolve metal) Sigg bottles are safe to transport anything people can drink, and are BPA free. Overall, I’m extremely happy with the bottle, and it’s 20 oz (0.6 L) capacity is a good compromise between portability and capacity. The $30 price struck me as high until I held the thing - the quality is top-notch, and chances are you’ll never need another water bottle. Which means less crap in our oceans, and I think we can all agree that’s a good thing.

Filed under: Other — Max @ 3:14 pm

Welcome to part two (of two) of my Xbox repair experience. See part one here.

6.19.2008 - My Xbox arrives unannounced. I become excited as I realize what is in the box, and the UPS guy backs away slowly.

Continue reading The Day My Xbox 360 Was Resurrected

Filed under: Toys | Games, Video Games — Max @ 10:04 pm

My 360 hasn’t exactly been a model of high-tech gadgetry. In fact, it’s almost surprising it worked despite a number of scary ailments:
1) It liked to freeze and make clicking noises. This happened both at certain points (loading Treasury in GRAW) and randomly (about 1/2 the time during a Madden game).
2) The drive tray wouldn’t close by pushing the button - the tray itself needed to be pushed gently, so it began to close, then once it reversed itself and opened again you could push the button to close it.
3) On rare occasions, you might get a black screen and the infamous RRoD (Red Ring of Death), which would be fixed upon rebooting.

Needless to say, it’s days were numbered. Here is the story of the end:

5.29.2008 - My 360 dies.

Continue reading The Day My Xbox 360 Died

Filed under: Toys | Games, Video Games — Max @ 7:47 am

Get Smart has been getting some pretty mediocre reviews, but I really liked the movie. Maybe it’s because I have the comedic tastes of a 5 year old, or maybe it’s that I grew up watching Get Smart on Nick-at-Night. Possibly I have a huge crush on Anne Hathaway, and the fact that no matter what I see him in I always enjoy Steve Carell certainly helps, but I really found this to be an entertaining movie. It’s a simple movie. Simple comedy. Fairly impressive action scenes. Nothing more. But it accomplishes what I want summer blockbuster’s to accomplish: entertain me at a level comparable to that of my ticket price. If you’re looking for the best of Steve Carell’s comedic abilities, look elsewhere. If you’re looking for a faithful recreation of the original Get Smart series, look elsewhere. But if you want to plop your butt into a nice air-conditioned theater this summer and have fun watching a simple action packed comedy, then this is your movie. I laughed my ass off and had a great time watching the movie, so it’s got my seal of approval!

By the way, if you haven’t ever seen the original series, you’re seriously missing out. I highly recommend heading to amazon.com to grab a few old episodes.

Filed under: Media | Entertainment, Movies — Santi @ 7:32 am

Flipping through the back of Dwell Magazine, I ran across an ad for some familiar-looking art; the familiarity was born in high-school biology class when we did a gel electrophoresis experiment. Gel electrophoresis is commonly used for analysis of DNA and other proteins. DNA 11 on the other hand, will do this analysis on a DNA sample you send them and prepare a work of art based on the results - artistic license seems to be minimal here, with the customer specifying size, color, and other options. In a very real sense, however, this is both a family and self portrait - it’s a picture of the blueprint from which you were built. If that’s a little too much to advertise, they also create portraits from fingerprints and lips; both with striking and less-abstract results. And with prices starting from $190 ($390 for DNA), it’s probably cheaper than commissioning a more traditional work of art to fill that blank spot on the wall.

Check out the gallery at www.dna11.com.

Filed under: Art | Design — Max @ 6:29 pm

Girl Talk’s new album dropped today. But don’t go looking for it at your local record store; it is only available on the interwebs (until September 23rd, that is). Following the footsteps of Radiohead, Nine Inch Nails and a few others, Girl Talk is making the album available for a price of your choosing. There is, however, an incentive (other than the salvation of your mortal soul) to paying for the album. A $5 contribution nets you the sweet, sweet nectar of the album in lossless FLAC format and the whole album in one, unbroken file (Those familiar with Girl Talk know this to be a desirable item). A $10 contribution gets you all the above and the physical CD package when it hits brick and mortar stores on the 23rd day of September.

For those not paying, you still have access to 320kbps MP3 audio, albeit after some careful questioning regarding the ostensible music theft in progress.

For the unfamiliar, Girl Talk is a mash-up artist who takes samples from literally dozens of songs and remixes them into one song. A Girl Talk album will easily have hundreds of samples on it, laying track over track for some very unexpected successes. Imagine Notorious B.I.G.’s first verse from Juicy over the music to Elton John’s Tiny Dancer. Or Three 6 Mafia’s Stay Fly over Fleetwood Mac’s Little Lies. It’s kind of like the Matrix, you have to experience it.

Go get the album. You can always pick it up, listen to it and go back and pay what you think is appropriate. Can’t really beat that.

Also, previous albums are on Amazon. Night Ripper is the place to start. It’s hot.

Filed under: Music — Roy @ 9:25 pm

If you’re not familiar with Etón, they make cool portable radios that are powered via battery, crank, and solar power. Radios have FM, AM, and NOAA (weather) tuners. They also include cables to attach your phone to the device, so you can use the solar cells or hand crank to charge up. Some of the fancier models have flashlights, sirens, and two-way walkie-talkies built in as well.

They have found maybe the best possible partner: The American Red Cross. Red Cross provides help to those in need after natural disasters. Etón radios provide the ability to keep up to date on news and announcements even if you have no access to batteries or wall-power.

I played with some of the Etón products when I was at CES, and I think these are solid products. They may be a bit pricey, but they are well constructed and provide features that others simply just don’t have. In addition, when you buy an American Red Cross by Etón product, a portion of your purchase goes to help rebuild communities that have been hit by natural disasters.

You can check out the Etón line at Amazon.com.

Filed under: Gadgets | Technology, Portable Audio — Santi @ 8:06 am

I’m all about breaking records, especially when they involve not choosing Internet Explorer. Tomorrow is Firefox Download Day. They’re releasing version 3.0 of the FF browser and want to break the Guinness World Record for ‘Most Software Downloaded in 24 Hours’. Firefox is a great browser; I switch between it and Safari and I’d like to think my browser situation is pretty well-covered. Anyway, pick it up tomorrow. Unlike most stuff on this site, it’s free. And you’ll be part of history. Just think, years from now, you can tell your grandkids that you and 1,460,148 friends helped break the world record for… Yeah, nevermind, your grandkids will have probably left the room by now.

Link

Filed under: Computers — Roy @ 9:11 pm