Over the years our family’s car “fleet” has changed to where the majority are powered by east-west* engines (mounted sideways), instead of the old north-south arrangement. My pickup truck is now the lone holdout with the engine arranged longitudinally turning a driveshaft. It seems that, regardless of brand, the sideways engines are arranged facing to the right (what used to be the front of the engine is now facing toward the side opposite the driver). So my questions:
Are all sideways engines mounted this way (right facing)?
Is there a reason (beyond convention)?
Are there front-wheel-drive cars with conventionallly mounted (north-south) engines?
Why did manufacturers start moving to the sideways arrangement?
Bonus (in case someone knows): What is the largest displacement engine which is in a sideways configuration? (it seems that its always smaller engines mounted this way)
*east-west, north-south; sorry about the wording. I don’t know the exact terminology for this.
I believe the reason for transverse engine placement is: 1- the move to front wheel drive for most cars, and 2- space saving design.
I would WAG the reason for longitudinal mounted engine is that it’s easier to send power through a drive shaft to the rear that is centered in the midline of the car, the need for more space to mount the engine and transmission back then (the engine compartment could be made as long as needed to accommodate the engine size, not so if the engine is mounted transverse as there is only so wide a car can be made).
1)No. Off the top of my head, Honda and Mitsubishi both either make engines with both orientations or switched from one to the other in recent memory.
2)WAG: Something to do with the weight of the engine balancing with the weight of the driver perhaps. It was explained to me once but I don’t remember.
FWD Audis and Subarus have this arrangement, mostly because their FWD models are base trims of models with AWD, and they like to keep their AWD transmissions, with front driveshafts on the sides, in line with their engines. This arrangement causes problems for handling because it forces the engine to sit far forward of the front axle, making for a very nose heavy car.
Other FWD cars with longitudinal engines include:
The old Honda Legend sedan and coupe.
most Chrysler cab-forward cars
Renault 5 (“le car”)
Old GM full sizes like the Cadillac Eldorado and Olds Toronado.
Assuming you are excluding mid-engined supercars, I suspect the 5.3l LS4 V8 in the outgoing Pontiac Grand Prix GXP and Chevy Impala SS is the biggest, followed by the 4.4l V8 in the Volvo XC90. I would bet the Volvo engine is physically larger than the Chevy engine (OHC vs OHV) Volvo and Landrover also use transverse mounted I6s.
In addition to TW’s list, two of the earliest FWD cars had longitudinal engines; the Citroën Traction Avant and the Cord L-29 (the link doesn’t confirm the engine layout, but based on the pictures, I can’t imagine a transverse engine would fit).
Yes, the L-29 and the later 810 Cords had longitudinal engine orientations. So did the Citroen 2CV and DS.
But what nobody has answered yet is the original question of whether all transverse engines are pointed the same way; i.e, are the transmissions all on the left side of the car?
The Audi 4000 was a fwd drive car with a longitudinal (north/south) arrangement. The Audi 4000 was also available in Quattro AWD format, and mounting the engine longitudinally allowed this model to be offered in either 4wd or fwd.
I said they don’t. Older Honda engines had the transmission on the right, but newer engines like the K-series have it on the left. Mitsubishi 4G63 engines prior to 1996 had the transmission on the right, and after 1996 had it on the left.
Two come to mind that had FWD with unconventionally mounted north-south engines - the engines were in “backwards,” with the crank pulley next to the firewall. The Renault R-16 had the transmission frontmost, in line with the engine. The Saab 99 (and other Saab models of the general era) had the transmission underneath the engine. In both cases, this allowed much better weight distribution than with the engine north-south in front of the tranny, resulting in better handling.
The main reason is to reduce the amount of space needed for the engine, to make the car smaller (and therefore lighter and more efficient) as well as increase the size of the passenger compartment relative to the overall size of the car. If you imagine the engine as a grossly oversimplified 3’x2’ block, you can either have 3’ of the car’s overall length devoted to the engine if it is mounted north-south, or 2’ of the car’s overall length devoted to the engine if it is east-west.
Not only does the sideways mounted engine reduce the overall length of car space needed for the engine, but it also eliminates the drive shaft “hump” from the passenger compartment, leaving more room for passengers.
Mounting the engine sideways is just one of many tricks they have used to squeeze the engine into smaller and smaller spaces. Pop the hood on a 1970’s car and you’ll see all kinds of room inside of it. It makes the car easy to work on, but means there is a lot of wasted space. Pop the hood on a modern car and there is no room anywhere inside the engine compartment. They pack stuff in there like you wouldn’t believe. It makes the car much smaller, but everything is so cramped in there that it makes us idiot back yard mechanics cry every time we want to fix something ourselves. Seriously, on some cars you have to remove a panel in the wheel well just to get to the oil filter to change it.
There are plenty of “big” engines that are mounted sideways. My Cadillac has a transverse mounted 4.5 liter V8. The biggest I’ve personally seen was a 350 cubic inch (5.7 liter) engine in a Buick from a couple of decades ago.
