http://www.automobilemag.com/green/reviews/1008_2012_mazda_6_diesel_prototype/index.html

Quote :

"The new diesel, called Sky-D, is a 2.2-liter four-cylinder with two, sequential turbochargers. In the prototype vehicles, output is rated around 173 hp and a massive 310 lb-ft of torque, but those numbers will likely change slightly with the final calibration. At just 14:1, the compression ratio of the Sky-D is unusually low for a diesel engine. Typically, a low compression ratio causes issues with cold starts and low-load combustion, but Mazda has addressed those problems with increased exhaust-gas recirculation and a bowl in the piston that concentrates fuel below the injector to ensure ignition. Fine control of exhaust-gas recirculation is enabled by variable valve lift on the exhaust side. The low compression ratio also helps keep temperatures down, reducing the formation of nitrogen oxide emissions, and allowing the engine to meet emissions requirements without pricey exhaust after-treatment equipment. Mazda says the engine is good for 43 mpg on the highway in a 6 sedan, 1 mpg more than that in the smaller, less powerful Volkswagen Jetta TDI."

I don't know what to think. It's supposed to be high revving for a diesel, and 41 mpg with 310 lb/ft of torque sounds pretty sweet in a decent sized vehicle like that. But we all know Mazda and sequential twin turbos... there is so much technology in this engine you have to wonder if it will be unreliable and expensive to service

[Edited on August 31, 2010 at 2:52 PM. Reason : removed large pic]

8/31/2010 2:52:01 PM

Obviously a gasoline engine is more fun to drive than a diesel, but a diesel is worlds better than a hybrid or electric. So I definitely look forward to seeing more and more developments on the diesel front in the US.

8/31/2010 3:49:21 PM

Personally, unless it's a fairly dedicated performance vehicle (either sports car or at least something like, say, a 135i/335i), I don't give a shit about vehicle performance. If it's not a toy, and it's just a question of adequate transportation, I don't make any distinction between "slow" and "less slow". Like, if for some crazy reason I found myself in the market for a Camry, I'd get a 4cyl for sure. I'd rather just save the money on the purchase, as well as on operating costs.

...so yeah, in the 95% of cars that have nothing to do with being "fun to drive" to begin with, I'm all for what's economic and efficient.

8/31/2010 3:54:49 PM

^quite true. I mean, it blows my mind to see a woman insist on getting a V6 Accord sedan. You're burdening yourself with added expense....for nothing.

8/31/2010 4:02:57 PM

Put that diesel in a Mazdaspeed 3. Zoom Zoom.

8/31/2010 4:23:19 PM

Ray, I know perfectly well what to think. It's about goddamned time they did something like this.

Sequential turbos on a diesel are MUCH more common than on a gasser, and MUCH less of a fucking pain in the ass.

Ooh...I feel a fucking RANT coming on. You goddamned bastards better run for cover.

Fuck, Duke, I don't know why you don't think so, but I've had enormous fun driving the pure-t shit out of weaksauce cars...it ain't always gotta be about 0 to 60 in warp time to have fun. I've fucked fat chicks that were LOADS more fun (LOADS, get it?) than the few smoking hot chicks I've been with.

And who the goddamn fucking hell thinks diesels have to be slow, noisy, and stinky?

Pat, I've driven diesels that gave me a full-on chubby...gassers ain't always more fun.

8/31/2010 4:31:16 PM

Yeah, I'm not saying that you have to have big power to have fun. A Miata is SLOW, but still a lot of fun (and the fun increases proportionately with added hp).

I'm saying that if it's not a car that's pretty significantly focused on performance, I don't care about the power. 0-60 in 10 seconds is perfectly fine, as long as it'll run comfortably at 80 mph (i.e., not straining at WOT like my old 4-cyl Wrangler). All these family sedans with 250-300 hp are silly...I'd rather chop $5-10k off the price, get 5+ more mpg, lower maintenance costs, etc, and only have 120 hp.

8/31/2010 4:38:40 PM

Oh, I totally agree with you there, Duke. Totally.

8/31/2010 4:42:28 PM

RATTLE RATTLE RATTLE ZOOM RATTLE RATTLE

Just kidding I like diesels, or at least having the option. Electric cars are pipe dreams, diesels will make it happen.

8/31/2010 4:42:41 PM

Quote :

"Obviously a gasoline engine is more fun to drive than a diesel,"

haha, depends on what you consider fun. VIR=your S2000. dragstrip=my Dmax. i promise my truck will put a smile on your face, patrick. especially soon with new dyno numbers coming. what's even more fun is walking away from S2000s while pulling a landscape trailer.

8/31/2010 7:13:18 PM

I thought I read that it will redline at 5200 or 5500 rpm. That's like twice what the SuperDodge can do.

9/1/2010 12:45:32 AM

Mine will turn over 3k real easy. Fuel is what really limits me though

9/1/2010 3:13:07 AM

Quote :

"I thought I read that it will redline at 5200 or 5500 rpm. That's like twice what the SuperDodge can do."

Ray, close. Stock, the SD would limit at about 2500 rpm, with peak torque and horsepower occurring at roughly 1700 rpm. Now, she has a 3200 rpm governor spring. You can get upwards of 4000 rpm, but there's little to gain there; that is a heavy reciprocating mass and a long stroke.

Prechamber (or Ricardo chamber, after Sir Harry Ricardo) engines are capable of much higher revs than direct injection engines.

9/1/2010 9:16:19 AM

^ isn't direct injection "better," though?

9/1/2010 9:34:17 AM

under : a s2000 is a 14s car. It isn't even quick by modern standards. Hell a new camry can probably break 13s. Boooooooost is always good tho!!!

a modified 2ton truck is still funny. Don't get me wrong!!

[Edited on September 1, 2010 at 10:03 AM. Reason : .]

9/1/2010 10:02:11 AM

Quote :

"^ isn't direct injection "better," though?"

It really depends on the application. Sure, you get more power out of a direct injection engine, but its powerband is usually a bit more limited, and its NVH characteristics (noise, vibration, harshness for those of you who don't know) aren't as favorable.

The Ricardo chamber, or prechamber, indirect injected diesels have traditionally been smoother, quieter, and more suitable over a wider range of operation and/or high speed use, as the combustion event is delayed and smoothed out quite a bit.

However, with the advent of common rail electronic injection with fast-response piezo-electric injectors, that's not so much of an issue, as multiple injection events per cycle can occur, thus smoothing out the power stroke and custom tailoring overall burn rate and cylinder pressure rise to the required range of operation.

9/1/2010 10:45:43 AM

Brian I know modified boost HD trucks are fun, whenever I see one jetting around it puts a smile on my face, lol. However I was referring to the majority of diesels.

Quinn, the S2000 can hit high 13s...though how many times the drivetrain will sustain 6k rpm clutch drops I dunno.

9/1/2010 11:20:39 AM

I love my Passat TDI.

Y'know, except for the part about it being a VW and all.

9/1/2010 11:34:50 AM

The Mazda Sky-D uses lightweight components to allow higher revving. It does use piezo direct injectors as well.

It's interesting how gasoline and diesel technology are now converging.

9/1/2010 3:29:04 PM

I see what you guys are saying, but... a DSG VW GTI is a lot of fun to drive, as is an Audi A3 DSG, neither are particularly fast.

As for the Camry thing, screw a Camry/Corolla/Accord/Civic, for any reason. They make cars like Imprezas and the like, even a Mazda 3 w/a manual or something, anything but a snooze mobile. To me, even in the boringest of cars, how the transmission is shifted is way more important than power levels. I would rather drive a 30 year old Plymouth Voyager van than Toyonda Camcord from the last 20 years, and that's no joke.

9/1/2010 3:39:52 PM

Actually, one of the Voyager/Caravans with the 2.5 turbo and the 5 speed is pretty fun to drive, lol.

9/1/2010 3:48:07 PM

My parents' old Volvo 740 wagon was fun to drive, even if it had a 2.4 liter I-4 with 114hp, lol.

9/1/2010 4:18:11 PM

^^ if I found one of those in decent shape, the only thing that would stop me from buying it would be the questions of can I justify ANOTHER vehicle/where in the hell would I put it?

9/1/2010 10:22:21 PM

Quote :

"^quite true. I mean, it blows my mind to see a woman insist on getting a V6 Accord sedan. You're burdening yourself with added expense....for nothing."

Are you kidding? For the 75% of the driving population that doesn't insist on having a sports car or a toy + commuter, they are getting a ton of value out of being able to get in and out of traffic with more power than a 4 banger.

9/2/2010 5:57:52 PM

A lot of the females I know just have this "I need a V6" mentality and yet they never get on it really. They don't have a particularly aggressive driving style that would even be fully utilize the passing power of a modern 4 cylinder Accord etc. Modern 4 cylinder cars have as much or more acceleration than a lot of the old V6 models. For example, my friend's sister used to drive a V6 Grand AM (3.1 liter, 160hp). He had the car one day and we ran it against my dad's 120hp 99 Corolla (just screwing around for a minute). The Corolla was faster than the Grand AM from a 30mph roll. Both were automatic.

My sister has a 2005 Altima with the 2.5 4 cylinder. It's got adequate acceleration. The V6 would be pointless for her.

[Edited on September 2, 2010 at 6:19 PM. Reason : .]

9/2/2010 6:17:52 PM

^^ I'd say it's 90-95%, but I don't agree that they're getting a "ton of value". Almost any modern car has plenty of grunt to merge on an onramp or whatever else...200+ (and certainly 300+) hp is not needed, and is only rarely used by most people.

9/2/2010 6:57:06 PM

I remember going out with a girl a couple years back who had a V6 Accord...we were talking about them, as I have a 2003 Accord with a 4-banger and 5-speed.

She told me one of her "must haves" is a V6...what a crock of shit...she drove like a granny.

I seriously think that most people buy into a bunch of marketing hype over the V6 models. I remember a time when getting a six cylinder engine guaranteed you about 50 to 75 more horsepower over the 4 cylinder models, and back then it might mean you got 150 to 175 horsepower...but my current 4-banger produces as much horsepower as those earlier V6s did. Seriously, folks, there's no need.

9/3/2010 9:29:54 AM

But think of all the accidents you could accelerate out of, or into, or something. It's a safety feature!

9/3/2010 9:32:02 AM

Quote :

"Are you kidding? For the 75% of the driving population that doesn't insist on having a sports car or a toy + commuter, they are getting a ton of value out of being able to get in and out of traffic with more power than a 4 banger."

I think just about everyone in here is going to disagree with you. If you drive a 3000-3500lb sedan and need more than 180-200 hp to "safely" merge into traffic than you have bad judgement and/or horrible driving habits.

(every mid-sized family sedan these days gets 180-200hp from their 4 cylinder engines)

9/3/2010 10:55:33 AM

^^ I've avoided a few accidents that I wouldn't have had a chance of missing in anything but a sports car, but a V6 is definitely not a "safety feature" in the hands of 98% of people who drive Accords.

^ haha, if it's not a performance-oriented car, I don't really see much point in having >150 hp. You could have less than that in a 3000 lb car and still EASILY have adequate power.

9/3/2010 11:00:31 AM

mazda, pls to make the Shinari

http://www.youtube.com/watch?v=ARCyYS_tkDI

9/14/2010 8:03:49 PM