## Buick To Add Direct-Injection Ecotec 2.4L Four-Cylinder Engine To 2010 Lacrosse

##### 22 June 2009

A direct-injected Ecotec 2.4L four-cylinder engine will be the third engine offered in the 2010 Buick LaCrosse luxury sedan. With a six-speed automatic transmission, the new powertrain combination is expected to deliver fuel economy of 30 mpg highway and 20 mpg city.

The Ecotec 2.4L four-cylinder joins the lineup later this year as the standard engine in the LaCrosse CX. Direct injection technology helps it deliver 182 horsepower (136 kW) and 172 lb-ft. of torque (233 N·m). Buick expects about 25% of customers will opt for 2.4L-equipped models.

The 2.4L’s injection of fuel directly into the combustion chamber enables a higher compression ratio to increase efficiency and horsepower. Cold-start emissions are reduced by up to 25% with direct injection. Engineers tuned the Ecotec 2.4L engine to deliver greater torque at lower rpm and build it smoothly toward its peak at 4,900 rpm, giving the Buick LaCrosse excellent performance in all driving conditions.

Every engine in the LaCrosse lineup is direct-injected and matched with a six speed automatic transmission. Along with the Ecotec 2.4L, a new, direct injected 3.0L V-6 is offered and a larger-displacement, more powerful 3.6L V-6 is standard on the LaCrosse CXS model.

I would commend GM for this move, because I think it is the direction we need to go, but I really don't see Buick buyers buying a 4 cylinder LaCrosse. It will interesting to see if 25% of buyers opt for this engine. My guess would be much closer to zero.

Peter,

I think it fits with where GM "wants to take" Buick. They are trying to move the average age of purchasers down a bit for "entry-level" models.

Whether or not their attempts meet with reality are something I can not comment on...

I'm just curious as to what makes the Lacrosse expected to achieve worse fuel economy with the same engine that they will be putting into a small SUV...highway and city.

I am anxious to see GM put the engine into the Chevy Malibu where I believe it would do quite well (sufficient power, great fuel economy).

Smart move, but if I had to nitpick one thing, how is it possible that the same engine in the FWD Equinox gets 22/32? Weight is about even, and you would have to think that the Buick would be more aerodynamic...

I also would have thought it could be tuned for a bit more HP. The 3.0 in the Equinox puts out 264hp, and it the same DI/dual-VVT design. That would project to 211hp for a 2.4. It would have been smart to try to hit the 200hp barrier, especially for the mildly upscale Buick. The new 2.4 Hyundai with DI is supposed to hit 200.

Driveability not peak HP is what you want for a comfortable driving session. Buicks are about refinement. Retuning to provide a wide torque band will make the engine/transmission combination feel stronger and more comfortable in daily use. This is what Buick has wisely chosen to do.

By comparison, Chrysler had a transmission problem, or rather a lack of a good 6 speed. They tried to compensate by tuning their World engines for maximum HP and yielded a peaky torque curve, that made the engines seem underpowered. Drivers needed to rev them to produce much power.

Most drivers considered them crude and noisy as a result, leading to the downgrading of the cars the were meant to power, the mid-size Sebring and Avenger.

By contrast Hyundai took the very same World engines in a more sedate tuning, with a wide torque band, and lower peak HP, and they have been well recieived in Hyundai vehicles.

Bumping the peak hp up to 200+ would likely have very little impact on driveability. With VVT (especially on the intake valves) and DI, the torque curve is going to be pretty flat anyway. The old days of tuning an engine for either low-end torque or peak HP are behind us.

Again, my main comparison was to GM's own 3.0 that has the same exact technology, but a higher specific output. Early reviews on that engine in the new SRX indicate it still has a very flat powerband.

I think Buick's main concern should be perception and related to that, sales. Like it or not, there is a big perception difference of buying a luxury car with over 200hp and less than 200hp.

In any case, I'm more disappointed that they couldn't find a way to wring a few more mpg's out of this setup. They proved they could with the 2010 Equinox, so it doesn't make a lot of sense.

I think this is the right move at exactly the right time, for two reasons:

1)Americans are looking for efficiencies in the recession. By trimming a few hundreds/thousands off the price of an otherwise highly desireable vehicle, Buick could capitolize on a economic paradigm shift.

2)At $2.679/gallon (in Duluth, Mn) petroleum still seems cheap, so a four cylinder luxury car seems questionable. At$4.50 or more, a four cylinder model is a must if the vehicle shall be a success. Buick seems to be hedgeing against price shocks in oil.

I agree, however, that more that 20 city/30 hwy mpg seems low. Perhaps the gearing is lower to compensate for the small displacement, resulting in relatively high highway cruising rpms. Who knows...

In any even, engine downsizing combined with direct injection = smart.

P.S. If a small displacement luxury vehicle seems like an oxymoron, remember that the Mercedes and Jaguar have been building them for years for sale in the United States.

I don't think a 4 cylinder luxury car is an oxymoron. I think a 4 cylinder Buick is an oxymoron. Most people buying 4 cylinder cars are probably opting for something other than a Buick to start with, luxury or not. Mercedes has offered 4 cylinder cars in the US in the past but none of their sedans is currently available with a 4 cylinder engine. I don't think Jag has ever offered a 4 cylinder in the US. I just looked at Jag's website. It doesn't look like they even have a six cylinder these days. I believe both companies offer 4 cylinders (and diesels) in Europe, but not in the US.

Don't get me wrong. I'm not saying that I think a 4 cylinder in a Buick is a bad idea. I think it's a great idea. I just think nobody will buy it. People buying Buicks will opt for the six. People buying 4 cylinders (like me) will opt for something else.

@ Peter:

I only meant to imply that small displacement --not necessarily a four cylinder engine-- is not mutually exclusive to fine automobiles. The powerplants I had in mind at the time were M-B's now defunct 2.6 liter V6 which was once used in their C-class, and Jaguar's even more diminuative (yet equally abandoned) 2.5 liter V6 from their X-Type.

These engines both did the same job for their manufacurers that the 2.4 DI will do for Buick: to offer a lower price point, and to provide a fuel efficient alternative to big power/displacement luxo-yachts.

Add a turbo and displacement could probably go to 1.7Ls. V6s are and will continue to be a waste of...everything.

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