168 messages,
Last post on Oct 08, 2006 at 9:03 PM
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Diesel
#162 of 168 Re: I bet [nippononly]
by gagrice
Oct 07, 2006 (6:39 am)
Can an apples to apples comparison even be made vehicle-wise?
I think diesel technology pretty much parallels gas engine technology. They have added HP and emissions control and the mileage has not gone up. So I guess you can say it is better now. A lot of folks with diesel Rabbits got 50 MPG.
All the added emissions has dropped mileage. The truth is most of the improvement in air quality is a result of cleaner gas and diesel. I would like to see a valid study that shows the amount of pollution from 1970 cars and current vehicles. With a percentage blocked by emissions devices and how much was removed from the fuel to start with. I see old Mercedes diesels running around in CA and not blowing out black smoke. On a recent trip I noticed diesel PU trucks in AZ blowing black smoke. The difference is 15 PPM sulfur and 500 PPM in other states. I think perceptions will change when we get all the states selling clean diesel. CA mandated on road diesel have no more than 130 PPM in 1991 if memory serves me. Too bad they let the construction & ag business off the hook. Big bucks buy off politicians.
#163 of 168 Re: if my car had a diesel [nippononly]
by boaz47
Oct 07, 2006 (7:42 am)
You make a valid point about big trucks. Some people just would rather have a gas engine because it is quieter. They have improved diesel a lot and from inside the cab it is a fairly quiet ride. But from outside you know when someone is driving a diesel.
You are also correct in that diesels are less effected by weight. Because they get much of their torque at lower RPMs they are as dependant on weight to get their fuel mileage. At least to a point they aren't. If you had two cars like yours, one with a small diesel and one with your small gas engine their might not be a big difference in fuel mileage on a daily basis. The diesel owner would have to drive as carefully as you might to get their fuel mileage but they more than likely would only get a few more MPG better. However if you had a reason to place 4 people in your car and spent the day driving around town or up to the mountains to go skiing you would get a big difference in fuel mileage. The Diesel however would still deliver about what it did empty. That is how it works in trucks today. empty my 3/4 ton ford gets about 25 percent better fuel mileage than a 1/2 ton any other kind of Pickup empty. With a full load, and I can haul up to 12,000 pounds, I can get 50 percent better fuel mileage on a long trip to the river. We have tried it hauling the rock crawlers out to Johnson Valley. We have been pulling about the same weight as friends in a gas powered rig up and down hills to get to Johnson valley from Phoenix. The F-250 averaged 20 MPG and the Nissan Titan averaged 10 with a 7,000 pound load. empty we still go 20 to 22 and he got 15 to 17. I have no reason to expect less from commuter class diesels.
The real question is, how serious are we about fuel useage if we as a State are willing to sacrifice 25 to 30 percent fuel savings from the private fleet by restricting diesel and out of the same organization will allow the state and public fleet full diesel access? Does this honestly make sense to you? One of the largest users of diesels in California is the state itself? And if you think the lesson is lost on the people just look at what we are transporting our children to school in. If diesel is bad for us why are we putting our most precious resource, our children, into big yellow twinkies five days a week to get to school? And don't try telling me for a minute the kids aren't directly exposed to diesel fumes while riding in those twinkies.
#164 of 168 Re: if my car had a diesel [boaz47]
by ruking1
Oct 07, 2006 (11:10 am)
..."The real question is, how serious are we about fuel useage if we as a State are willing to sacrifice 25 to 30 percent fuel savings from the private fleet by restricting diesel and out of the same organization will allow the state and public fleet full diesel access? Does this honestly make sense to you? One of the largest users of diesels in California is the state itself? And if you think the lesson is lost on the people just look at what we are transporting our children to school in. If diesel is bad for us why are we putting our most precious resource, our children, into big yellow twinkies five days a week to get to school? And don't try telling me for a minute the kids aren't directly exposed to diesel fumes while riding in those twinkies." ...
Your quote is one of the reasons why I think this whole fuel savings issue is a "strawman" aka FAKE. BOGUS!!!!
Lets look at it from a fuel savings point of view. If you are truly interested in saving fuel why would you MANDATE and or chose the fuel that takes 37% MORE to do the same job!!??? Why would you mandate the majority of passenger vehicle fleet to use 37% more fuel when they can use diesel and use 37% LESS!!!??? Another way to look at is is why doesn't CA state convert ALL of their vehicles from diesel!!?? DAH they save 37% !!!!!!
This idea that diesel emissions can not and will not be mitigated "correctly" is another bogus illogical logic and almost knee-jerk reactionary attitude.
#165 of 168 Re: if my car had a diesel [ruking1]
by boaz47
Oct 07, 2006 (12:45 pm)
I think you are correct. But one of our big problems is admitting we made a mistake in the first place and are too proud to scold CARB or the EPA for allowing such a two faced sort of logic. Orwell simply had the wrong date.
#166 of 168 Re: if my car had a diesel [boaz47]
by gagrice
Oct 07, 2006 (12:53 pm)
I think you are right. He was 20 years off. CA banned the sale of new diesel cars in 2004. CARB did create a cottage industry for those willing to buy used diesel cars and bring them into the state.
#167 of 168 Better diesel fuel needed
by moparbad
Oct 08, 2006 (8:38 pm)
Better diesel fuel needed
quote-
Toyota instead urges an over-50-cetane number minimum and aromatics levels more like those of California Air Resources Board (CARB) diesel (averaging around 21%, although the default limit is 10%).
"It is essential that diesel fuel cetane and aromatics must improve," Toyota powertrain general manager Tetsu Watanabe said here. "Fuel quality is a big problem--low average cetane number (44) and aromatics are high--35% average and 54% maximum in the U.S."
Ironically, Toyota showed that its "DPNR" test car fleet in Europe is meeting European emissions and performance goals even in countries with 300-ppm sulfur fuels.
-end
CA has some of the best diesel in North America, and only the highest diesel emissions vehicles are permitted to burn it.
Even with ULSD diesel, the cetane is still a problem in the US.
#168 of 168 Re: Better diesel fuel needed [moparbad]
by gagrice
Oct 08, 2006 (9:03 pm)
I think BP/ARCO ULSD is 52 Cetane minimum. That is all I ever used in my Passat TDI. It ran great. I think we are awash in regulations and lacking the manpower to enforce the laws. If Toyota tested our diesel and found it lacking someone dropped the ball. I blame the EPA and CARB.