Definitely true - SAAB demonstrated this nearly 10 years ago, IIRC, when they introduced their Lambda-sond (or something similar) 32-bit ECU system. They took the exhaust from a '60s SAAB 96 2-stroke engine, fed it to the intake of a new SAAB, and the exhaust out the back of the new car was still emissions compliant. Even with ambient polluted air, the newest cars do clean it up!

I've read that an average gas-powered lawn mower emits more pollutants in an hour than 100 cars driving for an hour (or some such ridiculous stat). The continued tightening of auto emissions is pointless unless you control the other sources of internal combustion emissions and, most importantly, get the old beaters and gross polluters off the roads!

If California took the money spent over the past 10 years on electric car research, and had simply bought a new Cadillac to replace every old beater, they would have been far, far more effective in reducing overall pollution. Think about it, people would be buying electrics as an alternative to the ultra-low emissions gas engined cars anyway - effectively no difference in emissions (especially if you consider source emissions for the electrical generation). You really only need new cars on the road to replace the old cars to make a significant difference. Electrics and ZEVs are a huge (and ineffective) waste of money and effort.

Regards,
Gordon

 

To be fair Gord, you also have to consider two other things:

1) Greenhouse Gases from burning fuel - I know you and some others don't believe in Global Warming - no debates about this please!

2) The need for more oil and the related environmental effects from drilling.

I completely agree that a program for converting older/dirtier vehicles for new ones would yield more benefits.

 

You are going to have greenhouse gases no matter how clean the exhaust is, so I am assuming your comments are referring to general efficiency improvements of electric cars particuarly during city driving? Therefore, I am assuming you are commenting on Gord's "electric car development is/was a waste of time" statements? (You might want to edit your response so that it is clear that is what you are refering to.)

With that being the case, we can get equally efficient hybrid or fuel cell vehicles that are much much easier to use as electric vehicles. So, I agree completely with Gord. Why CARB is (or was recently) being so persistant about futher wasted developement in battery powered cars is beyond me and clearly lacks any engineering judgement (GM agrees and they are suing from the last I heard)

Hydrocarbons are a MUCH better source of energy for vehicles from a practicality and safety standpoint. The only thing that can change that is if some sort revolutionary super battery were created (none that I or the auto makers know of exists or even look promissing).

Now, if we had an abudance of non-hydrocarbon based energy supplies to meet our energy needs (autos are about 1/3rd of our energy usage as a nation), then I could see a reason to switch over to battery powered cars. But currently that is far from being the case. So as long as we need hydrocarbons for energy, those hydrocarbons should be used where they are most effective, in autos.

My concern is that if the RX-8 did infact have much better fuel economy with 247 HP as some of the early literature suggested, the stringent emissions did more harm than good.

It is sad that a truely wonderful engine is up against unreasonable demands. On top of that they have to test the catalytic converters for over 100,000 miles before they are sure they qualify? That is a brutal engineering requirement. (for instance, 100,000 miles at 60 MPH is 166 days of constant driving. You need 166 days to verify your catalytic convertor design works?)

-Mr. Wigggles

 

Mr Wiggles,
I was just playing devil's advocate with Gord to say that there are some benefits into researching electric vehicles - I'm not arguing for or against them vs. fuel cell, hybrids, etc.

If the stringent emissions requirement was ONLY the catalytic converter lifespan of 100,000 miles - then I'll agree with you completely. Certainly, it can be replaced (perhaps free of charge) at a certain mileage - which could ensure the cars operated with fully functional cats during their lifetimes.

Still, other manufactuers have to comply with the same requirements - so I'm not sure if the relative power between the RX8 and its competitors would be THAT different if these rules were different.

 

Revhappy,

It is my understanding that the rotary is especially difficult to design to meet the stringent HC requirement (NOx and CO aren't usually a problem). That is something that the cylinder world doesn't have to deal with. But that isn't my point. I don't think the Feds are being unfair to the rotary, I think they are being totally unfair in general - it merely the rotorary that is being hit the hardest.

By today's standards, an FD RX-7 would be a gross-polluter, (relatively speaking). Yet if everyone was driving FD's, I am sure our air would be at least somewhat better than it is today.

-Mr. Wigggles

 

I'm not so sure about that. There have been very big gains on cars like the RSX-S and EVO with changes to the exhaust systems.

I agree there is more bang for the buck in other things (as Gord suggested), but I still think high standards should be set. Still, there is a point where the law of diminishing returns reason its ugly head.

 

Hi Mr. Wiggles,

You have some good points. If people get too frustrated with the effects of more regulations, they may elect politicians who will choose to take a different path in the future?

Brian

 

Hi revhappy,

I'll post more about the additional EPA tests later on tonight. The new EPA regs for 2004 now test emissions performance at a simulated 120,000 miles (not 100,000 anymore). As an emissions-exempt vehicle for Colorado, the RX-8 will not need the usual yearly state inspection. (other states may have different regs?)

Brian

 

Point #1 above is one of the main concerns of the IPCC (http://www.ipcc.ch/) which has done the most peer-reviewed scientific research on the subject.

The main emission from the combustion of gas (petrol) is CO2. Vehicle carbon dioxide emissions aren't regulated by the EPA but are relevant in this context.

The level of CO2 emissions is mainly related to fuel economy.

 

Supplementary tests and the “Deterioration Factor”

The EPA and CARB felt that the old LA4 driving schedule didn’t “realistically account for the emissions effect of aggressive driving behavior, high acceleration rates or air conditioners' operation”. Auto emissions can be much higher with A/C operation and under high acceleration/high load events. Because of this, the EPA recently came up with 2 new tests that were designed to measure emissions performance in more “real world” driving situations.

CARB wanted the “aggressive driving/high acceleration rate” test to be run at stoichiometric air-fuel ratios for lowest emissions but this was unrealistic. High acceleration/high load driving with stoichiometric (14.7:1) air-fuel ratios led to temperatures that would destroy catalytic converters way before 120,000 miles.

The EPA commissioned studies regarding catalyst longevity and found that “a long period of time at 850^C can produce the same deterioration as a short period of time at 900^C”.

Since catalyst longevity is another goal of the EPA, they eventually agreed to allow “commanded enrichment” or richer air-fuel ratios under high acceleration/high load events. They then designed a driving schedule which tests high speed/acceleration/loads and called it US-06. It is 8.01 miles with an average speed of 48.37 mph, a top speed of 80.3 mph and many high acceleration events. Note that the top speed on the test is about 24 mph higher than the LA-4 (and higher than some state speed limits?).

Because richer air-fuel ratios lead to drastically higher CO emissions (and slightly higher HC emissions), the EPA eventually agreed to higher emissions thresholds for the US-06 test.

The new “air conditioning” test was called SC-03. The SC-03 driving schedule is run with the vehicle’s air conditioning on and is 3.58 miles with an average speed of 21.55 mph and a top speed of 54.8 mph.

Because of the strict emissions limits that are tested during the A/C operation test, we will likely see more manufacturers resorting to some sort of cycling A/C operation under full throttle now.

On top of the above additional tests, the EPA also calculates what they expect the auto emissions to be at “full-useful life”. For 2004 model year cars, this has been increased to 120,000 miles. Apparently, after thousands of hours of testing on new cars, an EPA “deterioration factor” can be calculated to estimate the emission system performance after 100,000 or 120,000 miles. Manufacturers must keep peak catalytic temperatures low enough to ensure that their cars can still pass the 120,000 mile emissions limits.

The current PCM (ECU) fuel maps in the RX-8 forces the engine to run very rich at WOT (wide open throttle). Although this hurts power and fuel economy, it keeps the cat temperatures low enough to ensure that the EPA 120,000 mile emissions standards are passed (lean a/f mixture leads to hotter exhaust temps, rich a/f mixure leads to cooler exhaust temps).

Note that any new RX-8 PCM (ECU) map from Mazda must have an EPA “deterioration factor” low enough to allow the 120,000 mile tests to still be under the EPA limits. It is somewhat comforting to know that the Mazda recently released new PCM fuel maps for the Mazdaspeed Protégé which led to large hp increases.

Small displacement, high-revving engines are most affected by some of the new regulations. I believe that the new emissions regulations are the main reason why Subaru decided to use a 2.5L engine for the new Sti and why Honda decided to use a 2.2L engine for the new s2000. Other manufacturers may still get by with “interim emissions limits” for the next 3 years but it will be interesting to see how many other small displacement “performance” engines will be replaced with larger displacement ones by model year 2007 (when ALL vehicles must comply with EPA tier 2 standards).

Below are graphs of the US-06 and SC-03 driving schedules:

 

If we have lost fuel economy due to Tier II, it might be doing more harm than good. Maybe something more reasonable like say LEV is in order?

-Mr. Wigggles

 

That's the whole problem. It would be political suicide for a politician to relax car-related air polution no matter how ridiculous the standards get. On a pie chart of total air polution, the amount of polution caused by late model autos is imperceptable.

Yet if say Senator Smith decided to reduce the requirements because they are stupid, Senator Jones from the opposite party would say something like, "With all of the air pollution these days, Senator Smith wants to reduce restrictions on autos? The enviroment can't take such poor decision making."

You get the idea.

-Mr. Wigggles

 

Because the manufacturers need the cat to heat up so quickly at start-up they have put it so close to the engine that it now getting too hot for WOT driving?

The net result: by being forced to make sure the miniscule amount of pollution doesn't occur at start-up, auto manufacturers now have to dump extra fuel during WOT, thus reducing power and fuel economy thus ultimately raising CO2 emissions.

CARB and the EPA are being just ornary at this point.

"You auto makers pasted our last tests. Now, just try and pass these. MUWAHAHAHA!"

I had a nightmare one time about a teacher making me memorize the phone book. This kind of reminds me of that.

As always Buger, thanks for the explainations and information.

-Mr. Wigggles

 

To help illustrate my point, here's some classic CARB nonsense from two years ago:

http://www.caranddriver.com/article....&page_number=1

My favorite quote regarding GM's clean but flawed EV1 electric car:

Also, pay special attention to the "Sticking It to Carmakers" on page 5. These CARB guys and their loyal supporters are never satisfied. The anamosity is most obvious from one board member speaking to GM:
As always, it is ultimately the consumer who has to pay for this.

As a clear demonstration, Tier II is 9 times better than the at-the-time super clean TLEV requirement of 1994. Is California's air 9 times cleaner today or going to be in the near future? No, I think not. It is time for CARB to cash a reality check: new consumer autos aren't the problem - you are beating a dead horse.

-Mr. Wigggles

 

The EPA is trying to both improve both emissions performance and fuel economy. Unfortunately, these goals are sometimes contradictory.

My understanding is that diesel vehicles are generally more thermally efficient than similar gas vehicles because they have higher compression ratios and have less pumping losses. The EPA likes diesels for their fuel economy but doesn't like the fact that they produce much more particulate emissions and higher NOx emissions.

They ended up creating a different set of emissions limits for diesels as kind of a tradeoff for thier greater fuel efficiency and in the hope that technology could reduce the particulate and NOx emissions further. That technology is coming around now and I'm sure that the EPA will be proposing tougher diesel standards at some point. They are a fun group aren't they.

Brian

 

... and that is the conundrum isn't it. That was the exact point I was trying to make. Whatever the case, people in the US will have to be frustrated enough by new regulations to vote for a change. If the frustration level isn't there by a large enough number of voters...

 

While we have made great strides in lowering toxic emissions since the clean air act, the EPA will be there looking for ways to make more strides.

We are actually lucky that the EPA decided against another test for "intermediate soaks". Since auto emissions are drastically higher before the cats warm up, the EPA and CARB wanted to design an emissions test so tough that the cats would have to remain at a high enough temperature to still work hours after the car was turned off!

To do this, additional insulation would be needed around the cats to keep the temperature higher. Of course that makes higher temps for high revving engines that much more of a problem doesn't it. NREL (National Renewable Energy Lab) actually has come up with an ingenious cat insulation design that has varying insulation levels depending on temperature. It is insulated so well that it can keep cat temps over 300^C after 12 hours of a car sitting, yet can conduct heat at high temperatures to keep the temps manageable!

Their design uses an insulating vacuum around the cat which has a small amount of metal hydride. Under high enough temperatures, the metal hydride releases it's hydrogen and the outside of the cat becomes thermally conductive (Hydrogen is pretty conductive). It is an amazing design but it would add much more cost to the already incredibly expensive catalytic converters and the EPA eventually gave in to the auto manufacturers for now...

Brian

 

I hear ya brotha! My C5 can hit 30 MPG highway doing about 75 MPH in 6th gear (only turning a little over 1500 RPM). Combined city/highway drops it into the low 20s....and when I'm at the track or drag strip....what is MPG...more like GPM....LOL!

 

I must say forcing (as the end effect of this regulation does) the use of rich air-fuel mixtures to ensure that catalytic converters last 120,000 miles is absolutely ridiculous. How costly could a Cat replacement be at X amount of miles???

'm sure the EPA did some study that found people wouldn't even bother (or know for that matter) replacing their Cat if it died (kinda like people who never do/get their oil changed).

All in all its ahuge shame if high-powered small displacement engines will be severely impacted by this. That coupled with the ever-increasing safety (i.e. weight adding) rules are not good things for the powerplants and cars we all love.

 

The EPA results for 2004 models are out and the RX-8 has extremely low emissions and very low DFs (deterioration factors).

As a recap, the 2004 model year is the first year for the new tier 2 standards. The main reason for the new tier 2 standards is to reduce NOx emissions. There are 10 different certification levels (or bins) that vehicles may qualify under. The lower the bin #, the tougher the standards are. Bin 1 is absolutely no emissions (no vehicle qualified for this bin). Only a special Honda Civic that runs on natural gas made Bin 2. The production Toyota Prius made bin 3.

Surprisingly enough, the RX-8 would have just made the bin 4 standard with the EPA results. In fact, the HC and CO emissions results for the RX-8 actually qualify well under the bin 2 limits!

.................................................. ....... HC ..... CO ..... NOx
EPA measured 6-spd RX-8 new ............. .0008 ... .9 ..... .028

US...... - Federal Tier II bin 5-A, California LEV2-A
Fed standards after 50,000 miles .......... HC ..... CO ..... NOx
.................................................. .... .015 .... 3.4 ... .05
EPA measured 2004 6-spd RX-8 level ... .0007 ... 1.04 ... .033

Fed standards after 120,000 miles ........ HC ..... CO ..... NOx
.................................................. .... .018 .... 4.2 ... .07
EPA measured 2004 6-spd RX-8 level ... .0009 ... 1.25 ... .04

I earlier mentioned that the new s2000 and WRX models used larger displacement engines to meet the new emissions standards. Surprisingly enough, both Honda and Subaru only qualified their new versions under temporary bins that will be phased out soon. The 2004 2.2L s2000 is qualified for bin 9 and the 2004 2.5L WRX is qualified for bin 10.

As I mentioned earlier, it will be interesting to see what effect emissions regulations will have on low displacement performance cars in the future.

Brian

 

bump

 

I'd like to make another observation here (and this probably applies to our European "combined" mileage test as well).

Looking at the speed profiles as posted by buger, the simulated driver in those tests cannot drive for toffee, and certainly does not understand 'green' driving.

In traffic flowing at any sort of speed over 40mph it is ALWAYS possible to smooth out the differences in the way the other cars are moving, just by choosing lanes carefully and leaving plenty of space. In the section where the driver is moving between 40 and 50mph they should be driving a constant 42-43 and ancticipating properly.

As with performance driving (and safe driving) there's 50% of improvement available through better driving before you make any changes to the car at all. Neither Europe nor the US are making much effort in that direction at all, as far as I can see - and it shouldn't be hard to sell that to the public, since it puts money directly in their pockets through better fuel efficiency.

I always beat manufacturer's figures by a significant margin; now I know why. (* "Always" means when driving in that fashion - not when I've gone out for playtime. )

Re driving in the highest possible gear to save fuel...

That's not necessarily true. In a piston engine it's best to pick a gear where you are driving at a good position on the torque curve but still a way off high power.

As an example it's more efficient to drive 30mph in 3rd than it is in 5th - and this also allows better car control. Basically, the rules that apply to running in also apply to fuel-efficient driving - don't labour the engine. In the 8 this seems to mean choosing a gear that lets you cruise around 3000 revs, but not any lower. This quite often mandates 2nd in urban traffic, which is strange until you get used to it...

I've had mid-twenties out of a couple of tanks of fuel now, including some queueing and giving it some beans when I have space.

Once you're up to motorway / freeway speeds I don't think it makes a fig of difference since aero drag is the major factor!