This time, I ran the oil 10 months and 7 days for 20,824 miles. As we can see, the wear levels are still good and the oil properties held up. I’m going to go for 25,000 miles next time. Also, I cleaned dirt that had accumulated near the oil fill hole on the engine. Not sure if some of it got inside and somehow dissolved in the oil.
It’s also time to change the air filter. I’ll change the filter and check the intake hoses. The whole intake system may get reworked if I get around to installing a carb-heat style hot air intake system to increase efficiency. Hot air ought to reduce pumping losses and may improve combustion a bit too. I got the idea while thinking through all the reasons fuel economy drops in the winter. Carb heat systems on aircraft are simple, like dryer vents that suck air from a metal scoop near the exhaust manifold, so it should be easy enough to add the same feature to my car. A more complex design could include a bypass that opens up whenever the throttle moves beyond a certain point. It would have to use its own spring and pull-only actuation so there’s less chance of a jam holding the throttle open.
I shopped for a replacement headlight for the Insight. Based on the claims of brightness made on the packaging (see below), the XtraVision seemed best because it’s brighter without sacrificing the warm color temperature of the basic halogen bulb. Yellower light is less annoying to oncoming drivers and improves sharpness and color rendering. There’s a reason shooters and racers wear amber lenses. “Selective yellow” is what it’s called. See http://en.wikipedia.org/wiki/Selective_yellow
I inspected the bulb filaments to see the difference, which led me to check the rated life of each. The standard bulb lasts 7 times as long as the XtraVision.
Allowing $40 of labor for purchasing, storing, and replacing 2 bulbs, the XtraVision costs $70 for 160 hours = 44 cents per hour = 0.7 cents per mile driven in the dark. The standard bulb effectively costs around 1/7th as much. 0.7 cents per mile just for the headlights is unacceptable given I try to keep the car’s maintenance costs below 10 cents a mile. The tires, oil, and brakes should be the main expenses aside from eventual engine overhaul. So, we’re going with standard bulbs until someone makes LED replacements that use warm white 2700K or 85+ CRI chips.
The spec sheet shows that all the bulbs have the same light output, which is probably why they have to put “Up To” next to each of the brightness claims. The more expensive bulbs are just a way to scam customers who want to pay more for a bulb that needs to be replaced far more often.
I changed the oil in the Insight for the second time, after 6 months and 11 days at 15,175 miles. I ran a MicroGreen filter and the recommended Mobil 1 0W/20 high fuel efficiency oil. So the total costs are $15 for the filter, $20 for 4 quarts of oil, $20 for labor, and $35 for the analysis. A $90 oil change is expensive, but this diagnostic report gives me valuable information and tells me I can go for 20,000 miles next time. Obviously, Bob says 16,000 because it’s not his car on the line.