BMW considers using smaller engines in ‘M’ lineup

omarrana submitted on 03/27/2008 Official AutoSpies Timestamp: 8:28 PM
from: www.egmcartech.com

[34] user comments | category: Misc News

Tags: BMW

BMW

In an interview with Auto Motor und Sport, Norbert Reithofer spoke about BMW killing the V8 diesel and replacing it with a more efficient twin-turbo inline 6-cylinder engine. BMW’s CEO also said that the automaker is considering using fewer cylinders in its high-performance M lineup.

BMW first launched a 4-cylinder engine in its M cars with the first generation M3. Following that, BMW’s M division started using 6-cylinders and today, the M5 sedan and M6 coupe use V10 engines producing up to 500-hp. In order to improve... Read Article

Comments:

Images hosted in your AgentSpace can now be posted in the comments section using the following syntax (case matters):
[img]IMAGE URL[/img]
Example: [img]http://agent004.myautospies.com/users/150/Sample-Gallery/sample1.JPG[/img]

GreenPlease - 3/27/2008 10:16:19 PM

0 Boost

They could take a couple of routes with this:

1. Turbo-charged I6 ala N54: instead of using two small turbos they could swap in a larger (and more expensive) VGT turbo while increasing the redline to ~7600. The larger turbo would keep the boost up longer (the Mitsubishi units on the N54 fart out after about 6000rpm) and could probably take output up to ~500hp.
2. Sequential turbo I4: BMW has experience with sequential turbos from their diesel program. The small turbo would have to be REALLY small though and I don't know if it could handle the intense heat. 2.0L with ~360hp wouldn't be unreasonable.
3. VGT turbo I4: similar idea to #1. 2.0L of displacement with ~350hp
4. High rev I4 with hybrid assist: the idea would be to basically make a screamer. Something with a 9500rpm redline making maybe 320hp out of 2.5L. The primary issue here would be unacceptable low end torque necessitated by the shortened stroke hence the need for a hybrid assist (bank of supercaps and a powerful starter-motor)
5. Turbo 2.0L I4 with Ricardo 2/4 stroke tech: this is a relatively new development where a hydraulic vavle train is used. The engine becomes either a 2 or 4 stroke unit depending on what the state of drive is. This is an eloquent solution and is capable of more than 160hp/liter while achieving excellent low end torque with a standard turbo. While at low RPM, the engine operates as a two stroke engine which has the advantages of having very high torque without increasing BMEP which would subsequently cause the engine to have to be overbuilt. The two stroke mode also lends itself to better fuel efficiency. Once the engine goes over ~2000rpm, the 4 stroke mode kicks in to prevent pollution problems.

Of these proposals, #1,3, and #5 seem the most likely. If BMW really wants to improve fuel economy and performance, #5 is the way to go. Hydraulic valve trains allow for a very fine tuning of an engine's power band which is right up M's alley.

Other evolutionary design changes that could be made would include:

1. Transverse engine mounting: this reduces the necessary length forward of the A-pillar and subsequently reduces weight
2. Rear transmission mounting: allows for better balance and puts some weight on the rear axle. This would also free up some room around the fire wall for a turbo
3. Ceramaic coating of the exhaust: reduces heat gain in the engine compartment and in engine coolant. This reduces the necessary size of the radiator and subsequently improves fuel economy through reduced weight and aerodynamic penalty.
4. Carbon reinforced plastic: certain body panels could be made of CRP such as the hood and trunk.
5. Use of a lithium ion battery: would require less space and weigh less than a lead acid or lead acid glass battery. The extra cost should be non existent with volume production.

All of that could probably save ~200lbs without costing too much to implement. Moving from the current V8 to option #5 would probably save an additi

reply to this comment

1995e34 - 3/27/2008 9:12:11 PM

+11 Boost

4 cylinders have been in luxury cars for decades. i think 6 cylinders is ideal for most (performance) cars, but it would be foolish to say that the 4 cylinder shouldn't even exist.

why is power considered a luxury but efficiency not?

reply to this comment

1995e34 - 3/27/2008 9:32:59 PM

+11 Boost

4 cylinders are slow? i know of some f1 cars with 4 cylinders.

reply to this comment

vdiv - 3/27/2008 10:49:47 PM

-2 Boost

Efficiency implies compromise, and compromise is an antonym for luxury.

reply to this comment

vdiv - 3/27/2008 10:58:28 PM

-3 Boost

If we're going to shrink the number of cylinders then why stop at 4? Why not go down to three, two, or even one cylinder engines? The next thing you know is an M3 with a Wankel engine... That actually may be a good idea :)

reply to this comment

1995e34 - 3/27/2008 11:10:44 PM

0 Boost

efficiency compromises power. power compromises efficiency. BOTH are compromises.

reply to this comment

AE86 - 3/28/2008 1:06:30 AM

-2 Boost

I have to nix the Wankel idea based on rubbish fuel economy. Aside from that, they do make a great engine and my first car was a 1981 RX-7.

reply to this comment

tattedtwice - 3/28/2008 1:39:43 AM

+8 Boost

"Amazing how desperate the Germans are now that Lexus has conquered global luxury markets. Now they're going to try to increase sales using smaller engines in performance cars. How pitiful. 4-cylinders have no place in a luxury car."

This site needs emoticons bad. If so I'd use one to show rolling on the floor laughing out loud, cause this here was hilarious. You should take that act on the road.

With all the past and recent smackdowns BMW has laid on lexus, it's clear which company is feeling desperate right now. BMW laying out plans to keep their cars agile and make them more fuel efficient has nothing to do with lexus, since it's clear lexus is the one that has a LOT of catching up to do.

reply to this comment

gooch - 3/28/2008 6:07:09 AM

+7 Boost

Seriously, get a clue. Lexus is chasing Mercedes and BMW. What is the IS series in response to? The 3. When they "F" up to GS, what will that be in response to? The 5. C'mon. As it is, the 335i and 550i will probably outperform or come close to the "F" cars; the Motorsport BMWs will far outclass the Lexuses. The Lexus brand is a nice, reliable car for people who want luxury but don't want to think about it. They're cars for passengers. The Bimmers are for drivers.

reply to this comment

Htay7500 - 3/28/2008 10:02:51 AM

+3 Boost

"Dude, 4-cylinders are unrefined and slow. Luxury is about power and refinement. Look at Lexus. No 4-cylinders and all their engines are best in class when it comes to refinement."

do you mind trying to tell us how? and because lexus doesn't offer 4-cylinders, they're having trouble in these markets. you need a background check.

reply to this comment

BMW4me4ever - 3/28/2008 10:08:29 AMView My AgentSpace

+5 Boost

Michael ... for the " supposed world class engines " that Lexus has, how many Engine of the Year awards have they won in the past 10 years? 1. BMW has won 19. enough said

reply to this comment

mscottc1 - 3/28/2008 10:40:22 AM

+5 Boost

MY GOD! Would someone please call the people at Cool-Aid and ask them to please stop selling the stuff to the Toyota/Lexus people? I mean, really- after all those people committed mass suicide a la Cool-aid, you'd ahave thought they'd be more careful about who they let get their hands on the stuff.

reply to this comment

VISO - 3/28/2008 12:57:43 PM

+2 Boost

Really, you must have your own set of mathematical principles that defy logic. How is 400,000 units for Lexus globally greater than (>) 1.2 million, 1.1 million, and 960,000 for BMW, MB, and Audi respectively?

reply to this comment

Rupert - 3/28/2008 8:08:41 PMView My AgentSpace

+3 Boost

The IS220d is a 4 cylinder!

reply to this comment

1995e34 - 3/27/2008 9:19:38 PM

+6 Boost

this is a move in the right direction. they need to invest in lighter vehicles rather than higher powered vehicles.

but this must happen from the top down as well as from the bottom up (size wise). many people don't want a less massive car because of the behemoths that occupy our roads.

i know, this article said nothing about weight saving, but i think it would go right along with decreased displacement.

reply to this comment

Brembo - 3/27/2008 9:28:44 PM

-1 Boost

I would had thought they would had made the 3.2l inline-6 with twin turbo.

reply to this comment

Brembo - 3/27/2008 9:29:06 PM

-2 Boost

or a smaller v8 with twin turbo.

S4cabriofoxone - 3/27/2008 10:16:40 PMView My AgentSpace

+2 Boost

A smaller V8 than what? The M3's 4.0L is much smaller than Lexus's 5.0L and AMG's massive (but awesome) 6.2.

Brembo - 3/28/2008 7:56:52 AM

+1 Boost

Back in the day. Car companies sold 2.5L v8.

adamsaf723 - 3/27/2008 9:56:34 PM

+3 Boost

What's wrong with a 4-Cylinder? The Evo X will throw you back into your seat just as hard as an M3.

reply to this comment

lexusis350 - 3/27/2008 10:32:13 PM

+8 Boost

If you ask me, the M-Series cars should have big engines. If, for whatever reason, you don't want the big engine, get the regular version instead of the M version of that car. Plain and simple.

reply to this comment

vdiv - 3/27/2008 10:45:54 PM

+7 Boost

Roger that. Time to bring the Isetta back to kick some SmartForTwo ass :)

bmwfan1513 - 3/27/2008 10:59:34 PM

+8 Boost

BMW is a company that can make that work.

reply to this comment

Yonder7 - 3/27/2008 11:26:36 PM

+4 Boost

What BMW is trying to do is feasible. Do you remember the Quad4 used in the Aerotech? more than 1000HP and 2.0 liters 4 cylinders. Now what they can try is find out how AMG create a monster of 6.2 liters 8 cylinders that is 3 kg lighter than the M3 engine with 4.0 with less power and torque, and then apply that tecnology to a 4 or 6 cylinders, (Mercedes should do the same with their 4 and 6 cylinders), then apply twin turbos and we should have an M3 with 400HP plus, but a lot lighter, which is the main success of the BMW cars on tracks.

reply to this comment

Yonder7 - 3/27/2008 11:35:42 PM

+1 Boost

Also 4 cylinders does not means that is cheap car. Do you remenber the Lotus Sprit?. I do not care about refinament if the car does a good work on tracks and BMW can do it. If MB try to do something like that, then they will losse a lot of customers that knows that MB are to heavy to use small power engines. As soon as they abandone Big engines I will be one of the first to start looking at other direction, may be Audi.

reply to this comment

AE86 - 3/28/2008 1:04:26 AM

0 Boost

All I can say is the next M3 better weigh significantly less than 3600 lbs AND I would prefer it to have an inline six.

reply to this comment

dwatson - 3/28/2008 1:14:10 AMView My AgentSpace

0 Boost

They made a limited edition E90 320si M model in the UK for either 2006 or 2007. It had some sort of awesome forced injection 4 cylinder.

They tested it on Fifth Gear and I'm sure you could find it if you go on Youtube. It was an awesome car.

reply to this comment

MaindrianPace - 3/28/2008 4:29:22 AM

+1 Boost

Yeah, IIRC this homologation special only had 175hp though, which wasn't a huge amount more than the 320i.. the actual World Championship winning 320Si race cars develop 275hp from basically the same engine, though, which is getting there :)

Rupert - 3/28/2008 8:10:54 PMView My AgentSpace

+3 Boost

The 320i is the weak engine in BMW's line-up - the 320d is more powerful, more economical, quicker and has lower emissions.

To post a comment for this story, you must first Login.

If you do not have an account, you will need to Register (It's Free!).

	omarrana I hooked up my accelerator to my brake lights. I hit the gas, people behind me stop, and I'm gone.
	View My AgentPage