BMW's in line sixes vs. V6s

[deutsch100]

Hopefully this is not too dumb of a question.....

My 330cic is my first inline BMW 6 cylinder. It seems like my inline 6 is the smoothest and quietest engine I have ever had. My last car was an SL500 with a V8...and my 330ci is quiter and def. smoother.

What makes BMW's inline sixes so smooth and refined? Every auto magazine raves about BMW's sixes....so why do American, Japanese and other German cars use V6s if inline sixes are so praised???

 

[PhatBimmer]

Good question I never thought of that let me think no idea because BMW is the best j/k no idea really.

 

[Pink_Floyd]

Because you can't turn an I6 sideways for use in a front wheel drive car. Actually, I don't really know the reason why, but thats one thought I had. The reason why they are so smooth is not only because of the design (BMW V8 and V12s are REALLY smooth too) but because they've had the I6 since the 70's they have really mastered that engine design. I really hope they don't go putting V8s in the 3ers any time soon.

 

[codex57]

Inline sixes are naturally balanced. If you do a search, you'll find a more technical explanation. But basically, an engine vibrates. The vibration creates noise and, well, vibration. On an inline six, the way the engine fires, it creates vibrations that offset each other which make the engine sound and feel smooth. Other variations use balance shafts to cancel out the vibrations the engine naturally makes. V6 engines need balance shafts for example. That's why a inline 6 engine feels smoother than a V6 one. V6 is more popular though cuz it fits in a more compact package. Leaves more room for the designer, safety equipment, etc.

 

[Section_8]

Lots of companies do offer and use inline 6's, but BMW's is the most refined NA one out there. It drives their entire 3 series cars and much of their Z3/Z4 and even 5 series vehicles. It's a proven engine style based on their F1 Williams engines, just greatly detuned for daily driving.

Lucky for us! [driving2]

 

[Chesty Bonds]

Yeah BMW inline sixes are certainly worthy of all the praise. What codex57 said was quite right - its the perfect firing order in an inline six which helps to deliver such smoothness and flexibility...not to mention that awesome straight-six growl[headbang]

V6s are more compact and cheaper to build and they also perform better in crash tests because they aren't as long and as such dont have the same tendency to intrude into the cabin. Having said that, BMW have really mastered the safety aspects anyway so its a double advantage in a BM! I was very dissappointed to hear that the upcoming M3 will feature a V8 engine.... Very sad.

 

[Nelson330ci]

Section 8 - are those 18s or 19 M3 rims on your 323? Car looks lowered...is it?

 

[TheBry]

Regarding the question why other auto mfrs don't use inline engines, I've heard that inline engines are more difficult to install and remove for service. I think that adds to the reason why most auto makers don't favor them -- it probably adds costs they're not willing to absorb (or pass along to the customer). Add to that the fact that you can't mount one longitudinally for front drive cars and you can see how the cons would outweigh the pros to value-minded auto makers.

 

[Ghost]

I agree with codex57, I think inline (and flat) engines are more balanced than V’s in which case the torque created is utilized to its fullest. I think when manufactures are more concerned with this available torque than with space they utilize this aspect more. Another reason the BMW torque curve is more flat than others.

The most powerful engine in the world is an INLINE fourteen cylinder.

If you want more torque just add this cam to your car.

 

[tool fan]

Holy shit!!!!!!!!!!! What does that thing power? That is HUGE

 

[Section_8]

Section 8 - are those 18s or 19 M3 rims on your 323? Car looks lowered...is it?

Yup and Yup. M3 Evo (new style) 18's (2 sets of the front wheels, the rears are too big to run staggered w/o rolling my fenders, plus I like the fact that I can rotate tires with them all the same size).

Koni Sports adjustable shocks, w/ Eibach Sportline springs. have it set 40/50 so it's a lil' tighter in the front, but not too stiff, since it's my daily.

I think the grass gives the impression it's lower than it is - I rarely have rub (speedbump, ramp) issues. I'm prolly 2 1/2 3 inches at least, probably more (a crushed soda can height).

Ghost - what the heck does that drive?? A hydro dam?? Imagine the torque on that!!

 

[MrElussive]

There are some FWD cars that have an inline setup. The 2.0 liter 4-cylinder enigne from VW is mounted sideways and is an inline engine.
This is a very non-specific statement, but basically BMW has been doing I6's for a long time and they know how to tune the engine to make it sound so good. I6's are also naturally smoother and produce more torque.

 

[Ghost]

...What does that thing power? ...

...what the heck does that drive?? ...

BIG Ships.

I hyperlink when I can, in my post click on "most powerful engine"

 

[Section_8]

doh! Nice find, that just looks like it could drive the planet somewhere if it had grip... Plug it into a natural oil reserve, slap 4 or 5 in a row, and step on it.

 

[Kirby]

See the starter motor in the lower left corner? That electric motor is like 10-15 hp just to start the big one!

 

[aNoodle]

The most powerful engine in the world is an INLINE fourteen cylinder.

If you want more torque just add this cam to your car.

Holy $%^@!

"Total displacement comes out to 1,556,002 cubic inches (25,480 liters) for the fourteen cylinder version."

Put that on a 3 series and call it the 325,480....maybe just the "325 THOUSAND" for short!!