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Old 07-24-09, 02:56 PM
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Okay, I was just wondering why have most car companies shifted form straight 4 or 6 cylinders to the V configurations of now. Is it just to have a shorter hood? Or is there a more beneficial reason?
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Old 07-24-09, 04:45 PM
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Originally Posted by Twan0690
Okay, I was just wondering why have most car companies shifted form straight 4 or 6 cylinders to the V configurations of now. Is it just to have a shorter hood? Or is there a more beneficial reason?
for toyota and nissan, from what i heard, the change from i6 to v6 was because of stricter emission requirements (in japan?)
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Old 07-24-09, 04:51 PM
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Ease of meeting safety/crash standards is a major reason, increased crush space and ease of packaging with V6 config.

Also for front wheel drive a shorter V6 works better for transverse mounting.
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Old 07-24-09, 09:24 PM
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Thanks, for the responses. I was just wondering because I read somewhere that the straight configurations were more balanced then the V configuration.
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Old 07-25-09, 02:27 AM
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they are more balanced, but are also heavier and take up more room.
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Old 07-27-09, 05:20 AM
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Emissions and fuel economy standards. The Toyota/Lexus I6 was a dirty gas hog. The I6's ran much smoother and more balanced, though.
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Old 07-27-09, 03:54 PM
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in line 6's are smoother, but require more space and can be heavier.
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Old 07-27-09, 10:37 PM
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I believe most of these problems could be solved with further development.
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Old 07-27-09, 11:30 PM
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Originally Posted by rominl
for toyota and nissan, from what i heard, the change from i6 to v6 was because of stricter emission requirements (in japan?)
small clarification, there are no V4's in decades except on motorcycles.
so car 4 bangers are all in line.

as for why the move to v6's, i suspect the main reason is the engine is physically smaller, or at least a shape with more flexible packaging options. with i6 the engine is long and can pretty much only be done longitudinally.
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Old 07-28-09, 12:42 AM
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what surprises me the most is that no one is going for the flat 6 configuration when porsche has proved time and time again that it realy works and in small packages too
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Old 07-28-09, 02:47 AM
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Originally Posted by biggie27
what surprises me the most is that no one is going for the flat 6 configuration when porsche has proved time and time again that it realy works and in small packages too
once again, it's another packaging issue. a flat engine configuration is very wide and exhaust manifold runs closer to the ground, which often interferes with steering (track gets too wide). porsche has the engine hanging behind the rear axle and its butt relatively slanted compared to the nose, so a boxer engine would be an ideal package for the chassis.
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Old 07-28-09, 04:39 AM
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Horizontal setup FTW.
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Old 07-28-09, 09:46 AM
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While the I-6 is the only configuration with natural balance, staggered cranks, balance shafts, and experiments with angles between the cylinder banks have eliminated much of the "buzziness" of the old straight fours and the "shaker" V8s.

Packaging is the problem today, and squeezing a moderate-displacement engine into an engine room that has to be shared an automatic transmission, torque converter, engine accessories (and often the electric motors that drive them), restricts the engine configuration to only a few options. Note the I-5, late of the Chevy Colorado and Volvo. While both engines were short on development, their vibration level was deemed unacceptable by the buying public. Too many compromises had to be made in the engine bay to squeeze in an extra cylinder. A balance-shafted V-6 is a better solution.
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Old 07-28-09, 11:16 AM
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Originally Posted by bitkahuna
small clarification, there are no V4's in decades except on motorcycles.
Saab, as far as I know, was the last manufacturer to offer a V4 in the American market.........as you note, decades ago.

so car 4 bangers are all in line.
Today's 4-cylinder powerplants, however, are not all in-line. All of Subaru's American market engines are flat "Boxer" fours or sixes. Same wth Porsche.

as for why the move to v6's, i suspect the main reason is the engine is physically smaller, or at least a shape with more flexible packaging options. with i6 the engine is long and can pretty much only be done longitudinally.
It's also easier to mount AWD hardware, extra differentials, and transfer cases to V and H-design powerplants than to a long, in-line 6, although BMW manages to do it with their X-drive products, and Volvo does it with a transverse-mounted I-6 in the XC90 (see my recent XC90 review).
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Old 07-28-09, 12:20 PM
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Originally Posted by Lil4X
While the I-6 is the only configuration with natural balance
Don't forget about its meaner cousin the V-12.
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