What are the merits of I6 engines over V6
12-19-2006, 12:56 PM
#11
Senior Members
Join Date: Dec 2005
Location: Seattle, WA Metro Area
Posts: 1,794
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by f?nf drei?ig' post='369239' date='Dec 19 2006, 04:34 PM
Surprised no one has mentioned horizontally opposed 6cyl.
12-19-2006, 12:57 PM
#12
Senior Members
Join Date: Dec 2005
Location: Seattle, WA Metro Area
Posts: 1,794
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by f?nf drei?ig' post='369240' date='Dec 19 2006, 04:39 PM
The V's cost more for the two heads, and if it is dual over head cams with cam phasing that is even more money. I don't think that 8 inches of forged crank would cost more then the affore mentioned parts.
12-19-2006, 12:59 PM
#13
Senior Members
Join Date: Aug 2004
Location: Bedford, MA
Posts: 408
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2004 530i 6-speed Titanium Silver/Black Interior
Premium Package
Sport Package
Aux input
30 GB video iPod
Cold Weather Package
Xenon
Red rear reflectors
Tint
Clear Bra
It really depends on who makes the engines... Honda makes some pretty good V6 engines (that run on regular gas too)
Originally Posted by the_oracle' post='369223' date='Dec 19 2006, 03:52 PM
The merits of a Straight 6 compared to a V6 is basically everything but cost!. A straight 6 is smoother, quieter more powerful. The engine is perfectly balanced. A V6 will never be a smooth engine because of the cylinders its missing. A V8 is perfectly balanced. One of the most expensive parts in a engine is the crankshaft. A V6's crank is half the length of a straight six engine. So instant $$$ saving already. Thats why Mercedes went the V6 route....... the cost and the length of the engine!, I read somewhere it was 30% cheaper to make their V6 engine than the previous straight six engine they made. Thats one thing of many why BMW rule!.
Lets compare the two....
First BMW (3.0 litre non turbo version)
Cylinders Straight 6
Capacity cc 2996
Stroke/Bore (mm) 88/85
Max output 258bhp@6600rpm
Max torque (Nm/rpm) 300/2500
Mercedes engine same capacity but V6 layout
Cylinders V6
Capacity cc 2996
Stroke/Bore (mm) 82/88
Max output 231bhp@6000rpm
Max torque (Nm/rpm) 300/2500-5000
Looking at the two, you can see that the BMW engine has much more power and rev's higher. This is because of the short stroke of the V6 gives it a natural disadvantage. The torque is matched, but the BMW engine is down on torque very slightly top end. Over 25 more horses and much better on fuel looking at the two car makers websites, the cats in the bag already!, on which one I would have.
Lets compare the two....
First BMW (3.0 litre non turbo version)
Cylinders Straight 6
Capacity cc 2996
Stroke/Bore (mm) 88/85
Max output 258bhp@6600rpm
Max torque (Nm/rpm) 300/2500
Mercedes engine same capacity but V6 layout
Cylinders V6
Capacity cc 2996
Stroke/Bore (mm) 82/88
Max output 231bhp@6000rpm
Max torque (Nm/rpm) 300/2500-5000
Looking at the two, you can see that the BMW engine has much more power and rev's higher. This is because of the short stroke of the V6 gives it a natural disadvantage. The torque is matched, but the BMW engine is down on torque very slightly top end. Over 25 more horses and much better on fuel looking at the two car makers websites, the cats in the bag already!, on which one I would have.
12-19-2006, 01:05 PM
#14
Members
Join Date: Jul 2006
Location: Bitburg Germany
Posts: 80
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2007 530i
Originally Posted by ImolaRedM' post='369248' date='Dec 19 2006, 10:56 PM
I did mention boxer engines. They're used mostly in Porsche and as well as Lycoming for piston engines used in many light aircraft.
12-19-2006, 01:10 PM
#15
Members
Join Date: Jul 2006
Location: Bitburg Germany
Posts: 80
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2007 530i
Originally Posted by Bedford530i' post='369251' date='Dec 19 2006, 10:59 PM
It really depends on who makes the engines... Honda makes some pretty good V6 engines (that run on regular gas too)
12-19-2006, 01:29 PM
#16
Members
Join Date: Sep 2006
Location: San Diego, CA
Posts: 190
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2004 530i stock.
2000 Jeep Wrangler non-stock =)
Not exactly the same car, but my jeep 4.0 I6 has been around for quite a while, about 15 or so years with very few changes. They just recently changed it to a smaller 3.6 or 3.5 V6 (I could have my liter numbers mixed up), but i think they honestly just changed it to say, "look, the jeep wrangler has an all-new engine taken from the almight Jeep Liberty!"
Anyway, the I6 was just a great running, low maintenance, stout little engine with enought torque (220lbs.) and horses (190) to please most 4x4ers and not run an enormous risk of trail breakage like you might with a big V8 in the bay.
Anyway, the I6 was just a great running, low maintenance, stout little engine with enought torque (220lbs.) and horses (190) to please most 4x4ers and not run an enormous risk of trail breakage like you might with a big V8 in the bay.
12-19-2006, 01:49 PM
#17
Senior Members
Join Date: Sep 2004
Location: Texas
Posts: 985
Likes: 0
Received 0 Likes
on
0 Posts
So if having a V6 is not really an improvement to having an I6, why would you advertise it and put a badge about it on the rear of the car?
Now I'm glad I've gone thru this thread, since all comments make sense and before reading it I honestly believed that having an engine with a configuration in V was always better.
Now I'm glad I've gone thru this thread, since all comments make sense and before reading it I honestly believed that having an engine with a configuration in V was always better.
12-19-2006, 01:57 PM
#18
Members
Join Date: Sep 2006
Location: San Diego, CA
Posts: 190
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2004 530i stock.
2000 Jeep Wrangler non-stock =)
Originally Posted by Wiu-Bimmer' post='369263' date='Dec 19 2006, 02:49 PM
So if having a V6 is not really an improvement to having an I6, why would you advertise it and put a badge about it on the rear of the car?
Now I'm glad I've gone thru this thread, since all comments make sense and before reading it I honestly believed that having an engine with a configuration in V was always better.
Now I'm glad I've gone thru this thread, since all comments make sense and before reading it I honestly believed that having an engine with a configuration in V was always better.
12-19-2006, 02:06 PM
#19
Senior Members
Join Date: Dec 2005
Location: Seattle, WA Metro Area
Posts: 1,794
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Wiu-Bimmer' post='369263' date='Dec 19 2006, 05:49 PM
So if having a V6 is not really an improvement to having an I6, why would you advertise it and put a badge about it on the rear of the car?
For the same reason they put HEMI on the side of trucks today. BMW was using domed combustion chambers (HEMI) since the 328 of the 1930's era. If you hype things up enough people will buy into it.
Bubbarosa, how many times did you change the exhaust manifold on the TJ?
The last Wrangler (TJ) was in production for 10 years; from 1997 to 2006. That inline 6 was used in one form or another since the 1960's (AMC).
12-19-2006, 02:28 PM
#20
Members
Join Date: Feb 2006
Location: Grantham. UK
Posts: 93
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2006 520d M-Sport / Silver Grey / Maple Wood / Black Dakota Leather / Heated Comfort Seats / Media Pack With Extended Voice Control / Space Saver Spare Wheel / Sun Protection Glass
The main advantage of an in-line six is cost of manufacture. It is simple and easy to produce. The bores are easy to machine and there is little duplication of parts. A technical advantages are the ease of producing tuned length induction systems, with a Vee it can become more complicated and simpler natural balance. The dissadvantages are mainly related to packaging. The crash structures in the front of a modern car need to collapse progressively. Solid Alloy or Cast iron doesn't collapse. All the force is therefore pushed into the passenger compartment. To comply with crash legislation the front end needs to be longer with an In-line Six than a Vee. Conventional wisdom says that this should result in a car with an In-line Six that is either longer overall, or less habitable. For some reason a BM is no bigger than a Merc or AUDI and has just as much space!
Mercedes first started to go for Vee engines when they were caught out by the race for Horsepower in the mid-nineties. They had to start shoehorning bigger engines into bodies that weren't designed for them and therefore developed a range of Vees. An example of this is their inability to fit the 3.2 Diesel into the "C" or "ML", a situation now rectified by the 3.0 Litre Diesel.
The first mid-nineties Vees were fitted to the SL, probably the only model that didn't really benefit.
Mercedes first started to go for Vee engines when they were caught out by the race for Horsepower in the mid-nineties. They had to start shoehorning bigger engines into bodies that weren't designed for them and therefore developed a range of Vees. An example of this is their inability to fit the 3.2 Diesel into the "C" or "ML", a situation now rectified by the 3.0 Litre Diesel.
The first mid-nineties Vees were fitted to the SL, probably the only model that didn't really benefit.