We've been subject to a littany of laments on so called "hybrid hype" in venues like "Automotive News," a daily industry journal, and "Autoweek," an enthusiast weekly. "Car and Driver's" Brock Yates rarely misses an opportunity to decry the "media weenies" (himself accepted apparently) who foist these awful hybrid drivetrains on an unsuspecting populace. Right wing attacks on hybrid cars have reached such a fever pitch that, last month, the EPA agreed to revise its gas mileage window sticker rating downward to reflect the right's sudden new embrace of "reality."

"WUNDERBAR," thought TPM's self appointed automotive blogger KingElvis. Revising the window stickers downward could be a sort of "back-door" method of increasing actual new car fleet efficiency, since the 27.5mpg passenger car and 22.5mpg "light truck" Corporate Average Fuel Economy standards aren't changing. "To make the standard under stricter 'reality' testing, cars would have to be more efficient," I thought upon first seeing the headline. But reading further down, your liberal automotive scribe learned a devilish detail. Turns out that it's actually the National Highway Traffic Safety Administration (NHTSA) that imposes guzzler fines and administers CAFE, while the EPA actually tests gas mileage. Neat trick huh?

Somehow the EPA will be generating two numbers a "real" rating and a "fake" gas mileage rating that will be used by NHTSA to adminster CAFE. Welcome to Bush's world.

Considering that hybrid cars have the highest EPA economy ratings, their window stickers will take the biggest hit in absolute terms. Bingo - the right wing now gets another rhetorical sword with which it can stab at its most reviled enemy: efficiency and conservation. However, the more "real" the rating, the worse off the anti hybrid lobby will be. Just for fun though, let's take a look at some of the right wing's "realism" criticisms of hybrids.

1. Hybrids get lousy gas mileage during engine warmup.

Yep - that's because ALL combustion engines run a very rich mixture during warmup to keep the engine from sputtering and dying in the cold. All cars have relatively bad gas mileage during warmup. This argument is particulary vexing coming from "experts" - have they never heard of a carburetor choke? Ironically, electric motors don't require "warm-up."

2. Hybrid EPA ratings are uniquely "unrealistic" and "unfair" because absolute gas mileage is many mpg lower than regular cars.

Just to be even handed, I credit "Car and Driver's" Pat Beddard who has pointed out the obvious critique to this argument. If the EPA window sticker ratings are 20% off, an SUV that gets 8mpg instead of the 10mpg rating is "only" two mpg off, while a 50mpg rated hybrid that gets 40mpg is a "whopping" 10mpg off.

Another point I would add that will be pivotal in the EPA's quest for reality. For jackrabbit starts and severe braking that we would associate with fast "realistic" urban driving that the right wing wants the EPA to take into account, hybrids have a major advantage. The electric motor allows the same jackrabbit break-away power with a much smaller gas engine compared to the same vehicle with just a big gas engine, and when the inevitable hard braking comes at the next light, the hybrid can regain some motive power through "regenerative braking" that a regular car just wastes in wearing down the brake pads. 

It's possible that under these conditions the EPA rating might give hybrids an advantage, but these ratings have gotten the "realism" treatment before in the 1980s, and that simply meant dialing down the numbers, rather than actually changing the testing method. This time though, the EPA is promising to use more "real world testing," so perhaps this will make the ratings for hybrids comparitively better than regular gas engine cars - though they'll all be lower. I predict that "city" fuel economy ratings will take a much bigger hit on regular engine cars than hybrids.

Before we leave this topic, lets take a look at a few engineering "miracles" that the industry has developed to save the big V8 engine. Predictably, right wingers like Brock Yates love to offer up these wonderful advancements as proof that their beloved "fire in the can" internal combustion engine, like rock 'n roll, will never die.

There are a number of advances, like variable valve timing and variable valve lift that have indeed improved power relative to engine size. But I'd like to take a look at a trick called "multiple displacement" that applies to larger engines with more reserve power - these are the big V8s and even a few V6s that waste worshippers worship. "Multiple Displacement Systems" allow half the cylinders in a "V" type engine to shut down under low load conditions. Like so many neat engineering tricks, this one has been around for a long time. In fact, in 1981 Cadillac actually produced a V8 that did the same thing. Although it worked on a similar principle, the slower 1981 microprocessors made the engine jerky when moving into shutdown mode, while today's systems are praised as "seamless."

The other reason the ol' V8/6/4 didn't stick around? It really didn't save gas. In any kind of brisk driving, it was just a big 368cubic inch V8. It really only kicked in during gentle highway cruising, and in that case simply using a lower revving axle ratio nets the same gas mileage gains.  

With the new "multiple displacement systems" used by GM, Chrysler and even Honda, the results are mixed. The new engines have much more horsepower on reserve than the '81 Cadillac, but you don't need any extra power to move the same weight at the same speed that you did 25 years ago. Mr. Newton's law's haven't been revised by Bush's science Pharisees - not yet anyway. So ironically, the fact that today's engines have about double the power of 1981 means that the same weight vehicle could shutdown cylinders more of the time than in '81. 

Predictably, the lighter the vehicle weight, the more of the time the "excess" cylinders can be de-activated. In short, the systems work pretty well in passenger cars like the 3700lb V8 Chevy Impala and the even lighter Honda Accord V6. The "as tested" gas mileage on these cars is pretty close to EPA ratings. Chyrsler's popular 4200lb 300C "HEMI" V8 benefits from MDS too, but obviously to a lesser degree, and EPA rating varies farther. Car and Driver has achieved "as tested" mileage of 19mpg on the similar Dodge Charger Hemi - not too bad but its rated at 17/25mpg by the EPA. "Consumer Reports" wasn't so lucky. They logged a miserable 11mpg on a 300C.

Now GM is trotting out the miraculous MDS system on its all new 2007 Tahoe SUV. Car and Driver's Tony Quiroga just tested one. I'll add the caveat that they used the remote starter to warm up the truck in the Michigan winter, so when idling, they were getting 0mpg. Still, that Tahoe is one big mutha - nearly 6000lbs. "As tested" C&D gas mileage? 12mpg. GM has been promising that the 4x2 version of the Tahoe with cyinder shutdown should average 20mpg. 

Conclusion? Auto writers like to talk about how we can't have conservation and efficiency because "you can't repeal the laws of physics." I'll admit that some pie in the sky notions from the likes of the NY Times' Tom Freidman regarding "plug in hybrids" push it a little. But then again, why do auto writers never editorialize about the most basic fact of Newtonian laws of motion? Big and heavy vehicles are going to take one hell of a lot more energy to accelerate than smaller, lighter ones. They love to decry the "magical thinking" involved in hybrid technology, and point out that the EPA ratings are too high, but they tend to be pretty silent on whether gas guzzlers don't make EPA ratings. Even with technological "miracles" in play, heavy trucks still guzzle gas, and decreasing weight remains the royal road to fuel savings.

The "laws of physics" continue to tell us that it makes no sense to excuse SUV buyers from the conservation equation. The "light truck" 22.5mpg standard must be jettisoned in favor of a universal 27.5mpg standard, and that should be based on the EPA's forthcoming "realistic" standard of testing that will first apply to 2008 model year vehicles. Makers can use more expensive materials like aluminum to offer big vehicles that are lighter - yes they will cost more, but then again, they're luxury vehicles already. Soldiers are dying in Iraq, partly for US oil interests - can't wealthy truck buyers pay a little more for the same size truck with more aluminum parts, or drive a 5000lb truck instead of a 6000lb one? Is there literally nothing they can do?