Though the conclusion is one that could perhaps have been guessed at using first-hand data collected at one’s local gas station, J.D. Power has released a compilation of statistics that tell us Americans are choosing more four-cylinder engines.
The smaller displacement and more fuel efficient engines are powering an ever larger percentage of cars on the road these days, and could be the number one customer choice in short order. Four-cylinder motors accounted for more than one-third of the cars sold in the first quarter of 2008, for a total of 37.9 percent of sales. That’s up 6.8 percent from 2003.
(Click through the jump to read on, including the full J.D. Power breakdown of engine choices.)
The four’s gain has meant less and less six-cylinder mills in service. While the six-cylinder engine is still the most popular in the U.S., with 39.8 percent of units sold, that number is down considerably from 2003 when sixes could be found in 45.6 percent of new vehicles.
The more powerful and thirsty eight-cylinder engines have always had a smaller portion of the market, but that segment is losing ground as well. Eight-cylinder sales have slipped by 1.9 percent from 2003 to 2008, currently owning 20.4 percent of sales.
Trended Engine Cylinder Mix—Total Retail Sales Percent of Total U.S. Retail Sales
1Q 2003 22.50% 45.60% 31.10% 1Q 2007 22.90% 40.80% 34.10% 2Q 2007 21.20% 39.00% 37.50% 3Q 2007 22.10% 39.50% 36.10% 4Q 2007 22.70% 39.90% 35.30% 1Q 2008* 20.40% 39.80% 37.90% *1 Q 2008 (January 1—March 8, 2008) Source: Power Information Network (PIN), a division of J.D. Power and Associates
For anything up to the size of a Fusion, I’d probably buy a 4-banger now, but that’s also dependent on the quality of the transmission attached. My Mazda 6i is a great momentum car…off the line at anything less than near WOT it’s a little slug, but once I’m on a roll, it’ll scoot. I can live with that if it means better fuel economy.
I often wondered why they put 4-bangers in the larger sedans and crossovers? If you need to get off the line at nearly WOT to make the car go, your fuel efficiency isn’t going to be much better than having a 6. No? It would be nice to see more turbo charged 4’s replacing the thirstier 6 cylinders. Any opinions on that?
Interesting that my Solstice gets damn near the same gas mileage as your car (19/28…yours 21/29) but has 104 more hp. You guys are gonna love direct injection.
Jason,
It all comes down to thermodynamics. You have to burn a certain amount of fuel to get horsepower, regardless of whether it’s in a 4, 5, 6, or 8 cylinder engine.
In general, piston style engines are the most efficient when running at their peak horsepower speed (which is generally near the maximum speed for the engine) in terms of work/gallon. To burn fuel, you need to combine it with air. Turbo charging allows you to put more air in a given size cylinder, which then allows you to burn more fuel.
Regardless of whether a given car has a 4,6 or 8 cylinder, the amount of energy required to bring it up to speed is the same; power is how fast you generate this energy.
The advantage of running a 4 cylinder is not generally found during acceleration, but when cruising. This is because the 4 cylinder will generally be working at a level closer to its peak, which means it’s running more efficiently than a 6 cylinder.
When driving down the road, your 200hp engine running at 2000RPM is not making 200hp, but more like 60hp or so. A 150 peak hp 4 cylinder is more efficient at generating the required 60hp needed to keep you moving than a 500hp V8.
The reason you need a 200hp is for acceleration. If not for this, there would be no reason to put anything larger than an engine sized for cruising.
The reason a Hybrid saves fuel is that instead of installing an engine sized for acceleration, they can install an engine size for cruising, and add power for acceleration from the batteries.
A 150 peak hp 4 cylinder is more efficient at generating the required 60hp needed to keep you moving than a 500hp V8.
I’m not sure I understand this statement. Could you elaborate please?
I imagine that it has to do with the significantly lower amount of rotational mass and friction that a small four has than a big eight.
Mena, I believe that would be the percentage of total output and lower revs.
I understand the flocks of car shoppers turning to inline-four motors in mid-size sedans. If you’re able generate an average of 27 mpg over 23 (and save $2,000 off the car’s price), that’s sensible.
The present line a medium and small vehicles powered by 4 cyl. engines have solid performance. They’re able to easily hit 60 mph at around 8 sec. That’s faster than a 1960s Ford Mustang or Chevy Camaro in low-range V-8 guise. (That’s a crack at the old-school V-8 muscle crowd demanding $30,000 for those cars.)
Never mind. Mena’s question was about the logic, I take it. My mistake.
Did someone forget to copy the headers from the spreadsheet on this post?
Mena,
In general, piston style engines are the most efficient when running at their peak horsepower speed (which is generally near the maximum speed for the engine) in terms of work/gallon. To burn fuel, you need to combine it with air. Turbo charging allows you to put more air in a given size cylinder, which then allows you to burn more fuel.
Regardless of whether a given car has a 4,6 or 8 cylinder, the amount of energy required to bring it up to speed is the same; power is how fast you generate this energy.
The advantage of running a 4 cylinder is not generally found during acceleration, but when cruising. This is because the 4 cylinder will generally be working at a level closer to its peak, which means it’s running more efficiently than a 6 cylinder.
When driving down the road, your 200hp engine running at 2000RPM is not making 200hp, but more like 60hp or so. A 150 peak hp 4 cylinder is more efficient at generating the required 60hp needed to keep you moving than a 500hp V8.
Oh well, I knew the V8 would lose traction because of the gas prices, I did not see the V6 taking a hit as well
Josh & Jason,
The reason you need a 200hp is for acceleration. If not for this, there would be no reason to put anything larger than an engine sized for cruising.
For accereleration you need controlled torque not hp. If you need torque use one of the new under 2 liter small Euro turbo diesels and you will find that 120 to 150 hp diesel can match a 200 to 250 hp gasoline engine for “git-n-go”. And cruise highway at 50 mpg or greater with ease.
These types of diesel engines make up 53% of new registrations in Europe. CAUTION: these engines are NOTHING like the “domestic” diesel (with truck engine family trees).
For comparable sized (wihin 5%) gas versus diesel, the fuel economy of the diesel seems to be up to 50% better than gasoline … at least that is the case with the GM (Saturn/Opel/Vauxhall) Astra. If you think I am kidding you can check for yourself at
http://www.vcacarfueldata.org.uk/search/
I think this is the best argument around for eliminating CAFE standards and letting the price of fuel determine what sort of vehicles the public buys. Do you suppose it is just coincidence that the sales figures for 4 cylinder engines seem to have risen and 6 cylinder engines declined with the price of gasoline?
A 4cyl just will never have that cool V8 rumble.
A 4cyl just will never have that cool V8 rumble.
chris
How about an MP3 hooked to the throttle with a big power amplifer?
Sorry, I could not resist.
Josh, thanks I guess. I was expecting more technical reasons for your statement not a rehash of what you just said. What Ducati and Jeb said actually makes more sense to me. But I have doubts that any of these statements are generic for all engines considering the design intent, materials used, etc. That’s why I was hoping for a more technical explanation. Guess I’ll be hitting the forums for more info.
H. Smith,
50 mpg in combined government numbers (the only way close to credible accounting) is done in UK MPG standards, which differ from American MPG standaeds. A 50 mpg Euro saloon would likely average around the mid-thirties in the US standard.
Second, you’re “git-n-go” claim is questionable. A 150 hp diesel engine is NOT going to produce the same acceleration as a 250 hp gasoline engine unless you’ve been sniffing too many diesel fumes. If that were the case, the massive torque in diesel-powered passenger cars that have come Stateside from Germany, such as the R320 CDI and VW Jetta TDI, would have blazed through the streets. They didn’t. A 100 hp disadvantage is still a 100 hp disadvantage. Unless you have the 250 hp petrol car weighing a hell of a lot more (usually diesels suffer in weight, though), that’s not feasible.
The majority diesel claim in not continental. It is based in major market areas in Central and West Europe and Great Britain. The Italian, Iberian, and East European markets differ. Another factor in popular diesel markets is the cost: diesel costs as much or less than petrol because of state incentives, making a diesel purchase practical. That isn’t the case with this country’s largest market, Southern California, where diesel was selling for about 60¢ more per gallon over premium gas. That all but ended the diesel press here in the South Land.
While I always encourage intelligent discourse, let’s keep in mind these sales figures are from public consumption, and the public is generally not all that intelligent. What people see is the MPG numbers on the sticker, nothing more. It just so happens that a lot of those cars with high MPG happen to have 4 cylinder engines.
I recently sold my gas guzzling Frontier V6 (16-18 mpg avg) and went back to a 4 cyl Ranger. After I lifted it, I still get 25 mpg on average. It was about 28 mpg before the lift, but I couldn’t resist. Gonna get a few mods to squeeze out a few more MPGs.
[…] we learned that Americans are buying cars with four-cylinder engines in increasing numbers. With gas prices high and climbing, we can’t say that we disagree with that logic. When it comes […]
Mena,
My knowledge comes from a thermodynamics class from when I was in college. I don’t have all the specifics to reference, but my experience comes from lab experiments on a 3 cylinder, 22hp gasoline engine running on a bench with about 20 sensors monitoring pressures, temperatures, throttle position, and the dynomometer measuring output. From here we could see the change in efficiency of the motor as the throttle position varied the engine output.
What we learned in the lab was that as the throttle opened farther, the engine’s efficiency increased. I can’t recall the exact shape of the graph.
To restate in more general terms, a large engine working at partial output is not as efficient as a small engine operating at full output. You can cite any number of scenarios that seem to contradict that, but if you compare similar motors, built with similar technology, the engine sized closest to it’s peak output will be the most efficient.
The statements from Jeb and Ducati are factors that make the above true. The rotating mass is a factor. Another thing to consider is throttle position. To make a motor run at full power, you open the throttle all the way. This makes the air inlet as free as possible and allows unrestricted flow into the engine.
A large engine running at half power will use the throttle to restrict the airflow into the engine, creating an inefficiency.
Thanks Josh!!!! Exactly what I was looking for!
[…] [Source: Winding Road] […]
[…] Winding Road] Posted by admin Filed in In the […]
>A large engine running at half power will use the throttle to restrict the airflow into the engine, creating an inefficiency.
One of the reasons why diesel engines are more efficient than gas engines is that they do not restrict air flow into the cylinders - they freely breath max air at all throttle positions.
Cadillac CTS-V Laps Nurburgring in Sedan Record 7:59:32
Opel Insignia Hatchback Spied Undisguised 
The Rise of Hyundai: From Mitsubishi Borrower to Possible M-B Supplier
First Look At Possible New MG TF
So Long Super Aguri: Financial Woes Cause Formula One Team to Call it A Day
Send to a friend
HTML Formatting Tips
- To make something bold: <strong>Text to bold</strong>
- To make something italic: <em>Text to italicize</em>
- To make a hyperlink: <a href="URL">Text to link</a>
- To quote something previously said, you can use <blockquote>text</blockquote>
Markdown Formatting Tips (advanced)This site also allows use of Markdown formatting in the comment section. This accomplishes the same formatting as HTML but is typically easy to use.
my code* Second item
• Second item
1. Second item
2. Second item
<email@add.com>