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as engines get smaller, I'd like to see better proportions

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Old 06-20-17 | 01:09 PM
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Default as engines get smaller, I'd like to see better proportions

With smaller engines being used more, I want to see better proportions on cars. Not clunky big overhangs and small wheelbases.

Volvo's new lineup pretty much apes bmw RWD, even though it's FWD based.
Just look at the measurements.

If toyota and honda eventually do away with the V6, they should follow in volvo's footsteps.



Old 06-20-17 | 01:22 PM
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Well, we might (?) just disagree on this, but I like long overhangs. All else equal, while it may decrease maneuverability/handling and ease-of-parking, it adds weight in places that can help smooth out the ride and absorb bumps.......comfort, to me, is very important in a vehicle. That's why big American luxo-cruisers had such long overhangs for decades....it made for silky rides and huge trunk space. Obviously, a car that size would be impractical in today's dense traffic and driving conditions, but the general laws of physics remain the same....the long overhangs suppress up-and-down suspension motion transferring road-shock to the rest of the car.

.
Old 06-20-17 | 02:23 PM
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The main advantages of the short wheelbase include:
1) increase in torsional rigidity and bending stiffness of the platform, and
2) a smaller turning circle.

The disadvantages of the short wheelbase include:
1) greater wheel arch intrusions for the same cabin length, and
2) greater longitudinal pitching via squatting under acceleration & nose dive under braking.

In the Camry & Accord's case, they mainly use shorter wheelbases and therefore longer overhangs to alleviate costs, otherwise more stiff high tensile steel must be used, with thicker gauges, and larger box sections to compensate for loss in torsional rigidity and bending stiffness of longer wheelbases...
Old 06-20-17 | 05:15 PM
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Originally Posted by pman6
With smaller engines being used more, I want to see better proportions on cars. Not clunky big overhangs and small wheelbases.

Volvo's new lineup pretty much apes bmw RWD, even though it's FWD based.
Just look at the measurements.

If toyota and honda eventually do away with the V6, they should follow in volvo's footsteps.



I am not sure I understand the argument you have made? The overhang in the BMW Vs Volvo are so close. The BMW is shorter in the rear and just a 9mm longer up front. Can you elaborate?
Old 06-20-17 | 05:16 PM
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Originally Posted by peteharvey
The main advantages of the short wheelbase include:
1) increase in torsional rigidity and bending stiffness of the platform, and
2) a smaller turning circle.

The disadvantages of the short wheelbase include:
1) greater wheel arch intrusions for the same cabin length, and
2) greater longitudinal pitching via squatting under acceleration & nose dive under braking.

In the Camry & Accord's case, they mainly use shorter wheelbases and therefore longer overhangs to alleviate costs, otherwise more stiff high tensile steel must be used, with thicker gauges, and larger box sections to compensate for loss in torsional rigidity and bending stiffness of longer wheelbases...
Front drive cars will always have front drive proportions, and that's due to how/where the engine is mounted and the components needed to transfer power to the front wheels.

That Volvo despite the tricks it uses, clearly looks FWD compared to the BMW.
Old 06-20-17 | 05:24 PM
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Originally Posted by peteharvey
The main advantages of the short wheelbase include:
1) increase in torsional rigidity and bending stiffness of the platform, and
2) a smaller turning circle.

The disadvantages of the short wheelbase include:
1) greater wheel arch intrusions for the same cabin length, and
2) greater longitudinal pitching via squatting under acceleration & nose dive under braking.

In the Camry & Accord's case, they mainly use shorter wheelbases and therefore longer overhangs to alleviate costs, otherwise more stiff high tensile steel must be used, with thicker gauges, and larger box sections to compensate for loss in torsional rigidity and bending stiffness of longer wheelbases...
You kinda contradicted yourself from your first point to whereas you say the reason the Camry uses a shorter wheelbase.
Old 06-20-17 | 07:13 PM
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Originally Posted by mmarshall
Well, we might (?) just disagree on this, but I like long overhangs. All else equal, while it may decrease maneuverability/handling and ease-of-parking, it adds weight in places that can help smooth out the ride and absorb bumps.......comfort, to me, is very important in a vehicle. That's why big American luxo-cruisers had such long overhangs for decades....it made for silky rides and huge trunk space. Obviously, a car that size would be impractical in today's dense traffic and driving conditions, but the general laws of physics remain the same....the long overhangs suppress up-and-down suspension motion transferring road-shock to the rest of the car.

.
I'm with Marshall on this one, I loved this styling. While not as big, my 85 riviera was my favorite car I owned. I love the look, ride, and comfort. I could have cared less that it wallowed going down the road.
Old 06-20-17 | 07:45 PM
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The reason that transverse (side-to-side) engine FWD vehicles have a long front overhang is because the front differential (and therefore the front axle) is on the rear side of the engine. This places the engine ahead of the front axle.

The front overhang can also be made to seem longer due to a short dash-to-axle ratio, which is the distance from the base of the windshield (which usuallly coincides with the front edge of the front door) to the front axle. Vehicles with a (very) short dash-to-axle ratio have what is known as as "cab forward" styling and larger interior passenger volume. Chrysler used "cab forward" in the marketing of their large, LH platform cars in the early 1990s (Chrysler Concorde, Dodge Intrepid, Eagle Vision, Chrysler New Yorker, Chrysler LHS). The current-generation Lexus RX has cab forward styling and a very short dash-to-axle ratio.

In contrast, the new Volvos would have "cab rearward" styling, pushing the base of the windshield back to give a longer dash-to-axle ratio. I wonder if there is a lot of empty (wasted) space behind the front axle and in front of the A-pillar or if it is just a styling trick to give the perception of a longer dash-to-axle ratio. Because Volvos now only use inline-4 cylinder engines, the engine is very narrow and a shorter front overhang is possible.

Cars, such as the Camry, and RX and ES, which use a wide, V6 engine, will need that extra space in front of the front axle for the wider engine. This, of course, leads to a longer front overhang.

It is possible to place the FWD front differential in front of the engine, placing the transverse engine behind the front axle. Toyota did this on their supermini iQ model. Toyota has not used it on any other model and no other automaker (that I am aware of) uses this front differential placement.

Using a front-mounted FWD front differential would make a transverse engine-based AWD more difficult, as the drive shaft from the front-mounted centre differential would have to pass under the engine/transmission.
Old 06-20-17 | 08:01 PM
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Latest Lexus and toyota models seem to be purposely increasing the front overhang for no apparent reason. Lexus RX has the worst one yet I think. I don't think it has to do with engine size. FWD with transverse mounted engine has been the DNA of a lot of Lexus and Toyota vehicles, and yet the overhangs are getting longer.
Old 06-20-17 | 08:13 PM
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Originally Posted by Sulu
The reason that transverse (side-to-side) engine FWD vehicles have a long front overhang is because the front differential (and therefore the front axle) is on the rear side of the engine. This places the engine ahead of the front axle.

The front overhang can also be made to seem longer due to a short dash-to-axle ratio, which is the distance from the base of the windshield (which usuallly coincides with the front edge of the front door) to the front axle. Vehicles with a (very) short dash-to-axle ratio have what is known as as "cab forward" styling and larger interior passenger volume. Chrysler used "cab forward" in the marketing of their large, LH platform cars in the early 1990s (Chrysler Concorde, Dodge Intrepid, Eagle Vision, Chrysler New Yorker, Chrysler LHS). The current-generation Lexus RX has cab forward styling and a very short dash-to-axle ratio.

In contrast, the new Volvos would have "cab rearward" styling, pushing the base of the windshield back to give a longer dash-to-axle ratio. I wonder if there is a lot of empty (wasted) space behind the front axle and in front of the A-pillar or if it is just a styling trick to give the perception of a longer dash-to-axle ratio. Because Volvos now only use inline-4 cylinder engines, the engine is very narrow and a shorter front overhang is possible.

Cars, such as the Camry, and RX and ES, which use a wide, V6 engine, will need that extra space in front of the front axle for the wider engine. This, of course, leads to a longer front overhang.

It is possible to place the FWD front differential in front of the engine, placing the transverse engine behind the front axle. Toyota did this on their supermini iQ model. Toyota has not used it on any other model and no other automaker (that I am aware of) uses this front differential placement.

Using a front-mounted FWD front differential would make a transverse engine-based AWD more difficult, as the drive shaft from the front-mounted centre differential would have to pass under the engine/transmission.
........All good and valid points, but one other thing has to be taken into account in determining the size of the engine bay under the hood....enough space around the engine block itself for air to circulate and help carry off some of the heat. I've seen some Nissan designs where the engine fit in so tight that it was almost like a hand in a glove...with the result that the engine tended to run hot.
Old 06-21-17 | 12:40 AM
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Originally Posted by RXSF
Latest Lexus and toyota models seem to be purposely increasing the front overhang for no apparent reason. Lexus RX has the worst one yet I think. I don't think it has to do with engine size. FWD with transverse mounted engine has been the DNA of a lot of Lexus and Toyota vehicles, and yet the overhangs are getting longer.
Because the bonnet must maintain the same downward slope to provide space for the engine compartment, the nose cone must be lengthened to give slimmer headlamp look just like the refreshed Lexus 4.5GS below.















This mid 1980's Isuzu Piazza had a very long nose cone and front overhang, in order to achieve low semi-pop-up headlamps.


Last edited by peteharvey; 06-21-17 at 01:03 AM.
Old 06-21-17 | 04:34 AM
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Originally Posted by Mr. Burns

That Volvo despite the tricks it uses, clearly looks FWD compared to the BMW.
It doesn't to me, or any of the auto reviewers that have commented on it's RWD proportions. It's the most RWD looking FWD car I've ever seen.
Old 06-21-17 | 07:47 AM
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thank pedestrian crash test standards for making cars bloated
Old 06-21-17 | 08:09 AM
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Originally Posted by 4TehNguyen
thank pedestrian crash test standards for making cars bloated
This. Has nothing to do with size or shape of headlamps lol
Old 06-21-17 | 08:29 AM
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Originally Posted by SW15LS
This. Has nothing to do with size or shape of headlamps lol
I had heard that's what happened to the F series BMWs. Where suddenly, when the hood opened, the roundel was still there, it did not go up with the hood. What's hilarious is Mazda copied. With the G series, at least on the 5, it went back.

We've been stuck in this Dodge Intrepid styling for so long, I think many are used to it. Just don't buy the car. My preference is for inline 6's and RWD, and near 50/50 weight distribution.


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