Geoff Chadwick

It didnt say in the article - are they talking about increasing CAFE as a whole, a highway mpg requirement, or increasing the average of every car individually?

teal98

Okay, sure. But that is the whole point of this CO2 emission standard. I agree not to comment on whether it's a good idea or not

Well the main problem is that if the engine runs lean, you have a surplus of oxygen in the exhaust, which makes the NOx reduction catalyst ineffective. Now you could use the same tricks they use in diesels to get around this (NOx trap + some sort of elimination procedure), but that's $$$. Gas mileage would probably increase a bit.

You're thinking of the particulate emission equipment here, I think.


They're much less helpful in a CO2 emission standard, since the diesel emits substantially more CO2 for each gallon of fuel burned. For example, the VW Jetta diesel automatic at 29/40 MPG actually has more Carbon emissions (6.4 tons per year) than a whole host of gasoline powered cars, including the regular Cobalt (non-XFE), the Malibu Hybrid (mild hybrid), the standard Civic automatic, etc., at 6.3 tons per year.

Note that hybrids top the chart. The Prius is 4 tons per year. So what we really need is more hybrids. Diesels will just be an expensive way to fail to meet the standard.

Geoff Chadwick

Thats what I thought. I remember reading up on some gasoline engines that were running like 25:1 ratios with lean burn.

Well, the DPF is a big deal (in many ways) but in terms ofother systems (like urea injection) or excessive egr systems (Cat and Cummins have taken some different ideas on this). Either way, there is a lot of concern about which to do - as the Urea injection led to testing where mpg was better than the EGR systems, but it adds another fluid tank and everything associated with it.

I know, but I think when push comes to shove, mpg will be the bigger draw than c02 (and I'm hoping it does, as diesels have some serious advantages and I'd hate to see them written off again!). While DI and VVT will get gasoline closer and closer, it'll never quite be the same.

And yes, we really need hybrids. But hybrids cant help everything (like class 7/8 trucks for example... but class 5 trucks can get a serious boost).

teal98

Yes. Note that this is a separate discussion from this thread's title, as today's announcement had nothing to do with these heavy duty engine standards. The latest from Cummins and Cat is that Cat is getting out of the on-highway engine business and Cummins will be using SCR. I believe that only International is persisting in EGR for the NOx standard.


The CO2 emission standards that California is promulgating are for light duty vehicles and passenger cars. I believe trucks will continue with diesel (and CNG for those that can use it). For cars, I believe the California CO2 requirement will be quite a bit higher than market demand, making auto manufacturers do whatever is necessary to reduce CO2. I don't see diesel as being particularly useful in that endeavor.

So I think GM is making the right decision in avoiding diesel in favor of hybrids like the Volt, which will get a very low CO2 score in the EPA test, helping GM meet the California standards.

As an aside, there are a few southern California transit agencies that use gasoline hybrid bus power trains. Since you can no longer buy a new diesel down there, your choice is CNG or gasoline. If you don't have the expensive CNG refueling infrastructure (it needs more space too), you're down to a lack of choice -- gasoline.

Z28x

No, you get to decide what car I can't buy.

teal98

I sit corrected.

bossco

none

formula79

These kinds of laws are dumb. I mean for instance obeasity is a problem in the US. Well using the same logic as they keep applying to cars via CAFE....the way to fix it would be to make it so clothes manufacturers can only produce average and smaller sized clothing.

teal98

Or like making stores and restaurants sell food such that overall calories from fat from all food sold is less than 30%. I.e. McDonalds has to sell a low fat turkey burger for every Big Mac. If people buy too many Big Macs and not enough Turkey burgers, McDonalds gets fined.

SCNGENNFTHGEN

CAFE is BS and should be done away with period. Stupid fools aim to regulate this industry right out of business...Get your American Muscle now, while you still can, cuz the writings on the wall folks!! The jig is up....

Geoff Chadwick

1) I'd never trust a "turkey" burger from McDonalds.
2) I'd never eat one if they were forced to sell it .

I think the public actually *wants* more fuel efficient cars now. They just haven't learned how to avoid McDonald's and Burger King yet.

And outlawing "King Size" didn't solve anything. I've seen people go in and order a "Large" meal and then an extra order of fries.

The solution is for States and Cities to put in mass transit so people realize they don't need/want to drive everywhere. Cutting the emissions on NEW cars doesn't solve the millions of cars in LA. The old cars need to go.

And where there is no mass transit, people will drive as they have.

teal98

Even better. They'll make you take it so that they can avoid being fined, even though they know you'll just throw it away.

Z28x

That can be a chicken/egg type scenario. Also the mass transit needs to be cheaper or the same cost as driving, and it can't just run from 7am-7pm.

Lets face it, we all know the solution is higher fuel prices. With higher fuel prices the public demands more efficient cars and uses mass transit.

If the public was given the choice of keeping CAFE or adding a $1-2 gallon revenue neutral gas tax what do you think they would choose?

Chrome383Z

If it ever gets to the point that I can't buy a truck or large car; just to **** people off I have the skills to fix anything up.

I'll purchase a pre-emmission truck and throw a big *** 454 in it. I'll also get me a land-barge pre-emmission caddy and throw a 6.5 Turbo DIESEL in the bastard.

And spew black *** smoke as far as the eye can see, because I can, and because I think laws like this are insane.

Adam4356

this issue is such a steaming pile of crap.


Legislation on all of this is a joke. It's a political circus. Nothing to gain but tons to waste.