2008 Mercedes-benz C300 Sport Sedan 4-door 3.0l Manual Transmission on 2040-cars

Auto blog

VW joins Daimler's protest of new A/C refrigerant as EU deadline for compliance passes

The case of Dupont and Honeywell's refrigerant R-1234yf is doing the exact opposite of keeping things cool. The two chemical companies have spent years and hundreds of millions of dollars developing R-1234yf to replace R-134a, the new refrigerant shown to be 99.7-percent kinder to the environment than the one it is meant to succeed. Part of that development has been years of testing by governments, outside safety agencies and automakers to approve the chemical for use in cars. It passed the protocols necessary for the European Union to declare that new and significantly revised cars from 2013 onward needed to use R-1234yf, and mandated that every car as of 2017 must use it.
Enter Daimler AG. The automaker created a head-on collision test with a B-Class at their Sindelfingen test track that would lead to the pressurized refrigerant being sprayed on the engine. The result in 20 out of 20 test was that the refrigerant burst into flames as soon as it hit the hot engine, while Daimler says that R-134a does not catch fire in the same test. Another unexpected result of the R-1234yf test was the release of hydrogen flouride, a chemical far more deadly to humans than hydrogen cyanide, emitted in such amounts that it that turned the windshield white as it began to eat into the glass.
Said a Daimler engineer in a Reuters piece, "It was scarcely believable. The most complicated lab tests conducted using the most sensitive measuring instruments around found nothing and all we do is drive a car around a couple of times, open a tiny hole in the refrigerant line and the next thing you know the car is on fire." So Daimler said it wouldn't use the refrigerant, and it recalled the cars it had already shipped with R-1234yf.

Top horsepower-per-dollar cars in 2017

Bang for the buck. That quasi-scientific statistic is bandied about by motor heads everywhere from classrooms to barrooms, though the truth of the matter is that it's exceedingly complex to measure. A fair performance-per-dollar index would include something like cross-referencing MSRP (Manufacturers Suggested Retail Price) with point-to-point times on a track or driving route, which is obviously hard to do comprehensively. But, for the sheer joy of talking about cars and playing with a big spreadsheet, there's always the horsepower-per-dollar index, which is more straightforward, albeit hilariously flawed. There are vagaries even with this simple formula, of course: MSRP for vehicles can change at a moment's notice, to say nothing of the bottom-line shifting that happens with local deals or showroom negotiation. For this list we're running with the straight MSRP wherever possible, and as recently reported as we can get it. All the vehicles on this list are 2017 models, and all trims are reported where the lowest price and differing power levels intersect. Some choices were made for personal preference and some for sanity, avoiding things like all 48 trim levels of the Ford Transit, all with the same horsepower). If this list were a simple top ten, or even a top fifty, you'd be bored to tears with all the red, white and blue that is represented. Following perfectly with conventional wisdom, American cars really do lead the world where hp/$ is concerned. So, for the sake of variety (and the sheer joy of seeing a minivan 'win' one round of this thing) I've sorted out some top five and bottom five lists for broad power categories. Let's dive in. Less Than 100 Horsepower Okay, okay, this is hardly a category we'll grant you. But we've often tried to click off all the sub-100-hp cars on sale in the US, and making this list gave us an excuse. It also illustrates that none of these smallish vehicles bring cheap horsepower to the table - for that you'll need a motorcycle. The segment-leading Chevy Spark (above) asks just over $139 for each hp, and that Smart Fortwo Electric Drive has hp on sale for about the same price as its very distant family cousin, the Mercedes-Benz SL65 AMG (insert your favorite Smart joke here... we know you want to).

Test drive the Mercedes SLS AMG Electric Drive with Chris Harris

It's hard to not like the Mercedes-Benz SLS AMG GT. The all-aluminum coupe is fitted with a wonderful naturally aspirated 6.2-liter V8 delivering 583 horsepower and 479 pound-feet of torque. Not only does the burly combustion engine launch the two-seater to 60 miles per hour in less than four seconds, but it does so with one of the world's greatest exhaust soundtracks as it roars, burbles and cackles down the road.
But what happens when Mercedes-Benz takes away the V8 and its accompanying fire-burning song? Stripped of one of its most appealing assets, does the SLS lose its soul?
Chris Harris recently had the opportunity to take the Mercedes-Benz SLS AMG Electric Drive for a track spin in Europe. Sans gasoline, but with four electric motors providing a combined 740 horsepower (737 pound-feet of torque), all-electric all-wheel drive coupe uses sophisticated torque vectoring and a multi-mode operating system to put oversteer - drifting! - back into the equation. Fun? You bet. See for yourself, below.