http://www.autoblog.com/2006/02/21/b...ine-in-geneva/

 

Can this engine really be that much cheaper than the old 333hp 3.2 straight six BMW used to use in the e46 M3s?

Its kind of unusual (and disappointing) to see BMW going the turbocharged route. They have been building nothing but high tech NA engines for awhile now.

 

306hp... that's a familiar number.

Oh ya... that's exactly the amount of HP the IS350 has been using to mop the floor with the 3-series in acceleration tests ever since it came out.

Did BMW start feeling the heat that the 'old man's brand' was leaving their 330 in the dust from stop lights?

Interesting to see they had to (or maybe just wanted to?) go biturbo to produce the same power with the same number of cylinders that Lexus was doing N/A? (albeit with half a liter more displacement)

 

Of course they wanted to. BMW doesn't need twin turbo's on an 6cyl to produce 306hp. Let's not forget about the 333hp (now producing 343hp in the new Z4 M) 3.2 N/A I-6 that they have and have had available for some time now in their M cars.

They probably had their reasons for going turbo.

Looks like a nice motor.

 

Right, but were those reasons a matter of preference - like a more daily driver friendly power curve? Or are their higher power motors have a prohibitively high cost of production? Just wondering...

 

I'm actually considering the 3 series along w/ the Camaro for my current car's replacement. Two totally diff. cars I know, but it's what I like. W/ this 3.0 bi turbo this car will truly hall, too bad it will costs over $43k, which isn't bad, but that's just for beginers. I wouldn't expect this car to have all the options, as the Germans are typically quite liberal, knowing that you'll pick the latest and greatest tech which in turn jacks up the price sky high. Once you drive this car though, you can't get enough.

 

This engine was in development LONG LONG before the IS350 was even a thought. There was a lot of controversey on BMW turbocharging one of it's engines, but BMW has always been about defying convention. Kudos to Burkhard Goeschel.

 

from what Ive read the torque curve is friggin mountainous by 1800, and stays steady all the way to 5kish. its also supposed to be more efficient than the old 333 horse motor

 

If they are developing the same amount of power as the Lexus is NA then the turbocharged motor either:

1. Has a lot less displacement
2. Makes a lot more torque
3. Has less displacement and makes more torque

In this case it turns out to be option 3.

 

I take it they didn't weigh in an LS2 for comparison sake? I highly doubt the whole engine package, turbos included, is under 250lbs.

 

Neither is an LS2.

 

4. Tons more responsive. That it is.

 

This turbo has been in development for a number of years, so it's not a reaction to the IS350. Rather, BMW knew several years ago that the competition was going to have 3.5+ liter V6s, and that BMW could not significantly enlarge their inline 6's without making larger engine compartments in all of their models.

So to be competitive in power, they needed a turbo.

The next Mini will also be turbocharged. One theory that I've seen written about is that turbos+direct injection will be a more efficient, cost effective way to get high horsepower than larger displacement. In addition, an inline engine is easier to turbocharge than a V-engine. So the stars sort of lined up for this.

The 306hp number will be a DIN number, and it works out to a nice, round 225KW. Since it's a "technology announcement", I would think that an SAE-certified number for an actual production model would vary by a little bit from that. The Lexus 306hp is SAE certified, and works out to 228KW.

So I think the short answer is that 306 is a coincidence.

 

Apparently, you miss the point. They made it a point to say that the engine is 158 lbs less than a comparable V8. LS2 is somewhere around 400lbs, so this new Bimmer would have to be 250lbs to claim that.

 

That's not what he meant, or at least not how I read it. They claim that the engine weighs 150+ lbs LESS than a V8 of similar power (talking about 4 liter V8s). Todd is saying that they must not have included the relatively compact/light LS2, because if this turbo six were 150 lbs less than the LS2 weighs, it would have to be 250 lbs. In other words, this engine might be quite a bit lighter than a heavy, space-inefficient DOHC V8 of similar power, but it won't be lighter (by that much at least) than the much more powerful LS2.

That is how I took Todd's comment.