Hoovey689

iTrader: (16)

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mmarshall

Using that idea, though, it also makes one wonder why more manufacturers never used a V4 ....which theoretically could have been built on the same assembly line as a V6. The only one in my lifetime I can ever remember was on older Saabs, which followed the archaic, oil-burning, two-stroke, in-line three.

MattyG

I don't see an automotive use for a V4 because you would have the refinement of a coffee grinder in such a setup. Inline fours even if they're mounted transversely are still going to be smoother than a V4 setup.

It's fantastic to hear that MB is going back to inline sixes, even if it's related more to production savings vs anything else. This new setup should get some good reviews from driving enthusiasts.

Hoovey689

iTrader: (16)

Probably a pipe dream, but someone needs to bring back the Inline-8

LeX2K

V4 has worse NVH unless it uses a 90 degree configuration. Exhaust routing is more difficult and thus more expensive, intake system is more expensive. 2 cylinder heads instead of one, higher cost. It looks cool in a motorcycle.

I love the inline-6 engine.

mmarshall

In a modern sense, the main problem with a straight 8 would be packaging. Back in the days when straight-8s were popular (primarily in 1940s/50s-era Packards and Buicks), packaging was obviously not a problem with those long, narrow hoods and engine compartments. But that was not the main reason they were dropped. That was back in the age of carburetors and inefficient fuel-delivery, and the long intake manifolds needed for the straight-eight arrangement meant that the cylinders out on the end were always running lean (more air, less gas)while the ones in the center were running rich (more gas, less air). Yes, you could use more than one carburetor to even things out a little...but at the time, with that level of technology, it simply created more problems trying to hook the linkages up together and co-ordinate their settings. Automakers, on mass-produced cars, generally didn't try that till some years later. Automakers generally stuck to V8s after that because of the packing and fuel-delivery issues.

riredale

I guess there are several factors at play. The overall shape of the complete engine package would matter to a engineering designer. The increased cost of making two cylinder heads for a V6 rather than one (plus the added valvetrain complexity and weight) would probably be significant.

I've admired how the GM guys have poked a finger in the eyes of others by reworking the plain old pushrod V8 over the years to the point that it puts out a comparable amount of horsepower while being significantly more compact than the DOHC competition.

coolsaber

As long as their an audible delight (BMW i6s come to mind) onboard

geko29

No kidding. I can't find my favorite pic that illustrates this, but this one's not bad:



The engine on the right (on the stand) is a 6.0L LS1 V8. The one on the left (on the floor) is a Nissan VQ35DE 3.5L V6. Double the displacement, half the size.

Sulu

It seems that the 6-cylinder engine is the secondary engine at Mercedes-Benz. Some years ago, MB switched from inline-6 engines to far-from-ideal 90deg V6 engines, by "chopping off 2 cylinders from their V8 engine". Design the (important at the time) V8 engine first, then quickly derive a V6 from it.

Now, MB is switching back to the I6 engine by merely "adding 2 cylinders to their I4 engine". Design the (important now) I4 engine first, then quickly derive a I6 from it. It just so happens that the I6 is a much better engine design -- smoother, and less complex and with less parts -- than the 90deg V6.

LeX2K

That's a funny picture, the Nissan engine looks complete with all accessories the LS is mostly stripped.

mmarshall

Not surprising, when one figures that Chevy pushrod V8s (with a lot of modification and refinement over the years, of course), go back to 1955...an era of much greater simplicity under the hood.

Aron9000

GM did a complete clean sheet design with the LS1 V8 in the 1997 Corvette(this engine and its smaller displacement derivatives eventually went into every GM truck, Camaro/Trans Am, full size vans and full size SUV's). The LS series V8's have nothing in common with the old small block Chevy which traces its roots back to 1955. Not a single part is compatible between the two.

Granted, I will say the clean sheet design of the LS engines is a result of GM's expertise of decades of continual improvement/refinement on that old small block chevy design.

I had a couple of 4th gen Camaros with the LS1, one hell of an engine, especially in that lightweight car(3300lbs). Made a lot more HP than advertised(my 1999 made 305rwhp, about 350 at the crank), tons of low end torque to putter around with, but man it pulled savagely from 2500rpm all the way to its 6000rpm redline, you could never catch that engine out of its powerband and it never ran out of breath near redline, these cars were savage even above 100mph.


Getting back to Benz, I must say I am glad they are going back to the inline six. Nothing beats a straight six in terms of smoothness, refinement, and sound. Tune the exhaust right and they sound amazing. Plus its one of those things that you kind of expect with a luxury car, you can buy a 10 year old $7000 used Toyota Camry with a V6 and rip low 14 second quarter mile times. Why should your $80,000 Benz have the same engine configuration and a similar performance feel??? The turbo inline six is that difference maker, that special something that makes you feel like you bought something different, something technically superior by buying a new Benz.

mmarshall

A V12 will beat it in smoothness (and, in some cases, a V8), but V12s are so expensive to produce that they are confined to only top-tier luxury vehicles from British and German automakers.

The whole system of LS designations is so confusing that, as I understand it, it's hard to tell just what came from the original 1955 and what didn't. The main point I was making, though, is that the push-rod layout, still used in the LS block, goes back to 1955. Chevy has found that it is easier to get low-end torque that way.

Fizzboy7

Certainly great news for those, like myself, who want motor smoothness and refinement over all other things. Just about every review of BMW's once popular inline six were bursting with high praise. Would love to see such a motor filter down to Toyota, Lexus, and Honda products. Hopefully Mercedes will start a new trend here. Also refreshing to read a headline announcing a switch to something-6 instead of something-4. We've been on a downslide for about ten years as far as that goes (for better or worse).