Why are there no front-mid engine FWD cars?

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rationull

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My understanding is that the fact that the engine is mounted in front of the axle is part of the problem with weight distribution (and therefore handling) in transverse engine FWD cars. If this is the case, why are there no "front-mid" engine transverse FWD vehicles? It seems like the engine could be flipped to be behind the axle with the drive shafts coming out toward the front of the car instead of toward the firewall.

Front overhangs could be shorter, although granted the hood might need to be a little longer overall. It doesn't seem like it'd be any worse than a FM RWD/longitudenal setup, though, and it'd have the efficiency and overall weight advantages of the transverse layout. Would there be some kind of problem with the arrangement, or would it just not make enough difference to be worth the packaging differences?
 
i think people who are really looking for performance know to aim for a front engine, rear wheel drive layout car and there probably isnt enough demand for a true sports car that is front wheel drive.
 
They've been done. Have a look at the Cord.

Today, the idea just doesn't work, packaging wise.

For absolute performance in a 2WD vehicle, physics lead you to a rear-mid design. Though Porsche has been making a rather distinguished argument to the contrary for decades.
 
The 5 cyl Honda Vigor/Saber/Inspire would be the closest to it - north south engine with axles through the sump.
 
Originally Posted By: Silk
The 5 cyl Honda Vigor/Saber/Inspire would be the closest to it - north south engine with axles through the sump.

I really, really liked the '92 and '93 Acura Vigor. It was a highly under-rated automobile and a stunning car in a black/black color combo. They had a beautiful leather interior, that lovely inline-5 engine and a great 5-speed manual gearbox. I had the opportunity to spend time with just such a car and I still have fond memories of it. Of all the cars I had the opportunity to work with, the Vigor is one of the few that I would have bought without hesitation.
 
Originally Posted By: rationull
My understanding is that the fact that the engine is mounted in front of the axle is part of the problem with weight distribution (and therefore handling) in transverse engine FWD cars. If this is the case, why are there no "front-mid" engine transverse FWD vehicles? It seems like the engine could be flipped to be behind the axle with the drive shafts coming out toward the front of the car instead of toward the firewall.

Front overhangs could be shorter, although granted the hood might need to be a little longer overall. It doesn't seem like it'd be any worse than a FM RWD/longitudenal setup, though, and it'd have the efficiency and overall weight advantages of the transverse layout. Would there be some kind of problem with the arrangement, or would it just not make enough difference to be worth the packaging differences?

A longer hood means the car is bigger and weighs more overall. Given the inherent performance limitations of FWD, plus the fact that FWD is chosen for efficiency and packaging over performance, the extra overall size and mass aren't worth it.
 
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^ So were the Dodge LH cars. Still, you'd need front wheels sticking out like a forklift to get a reasonable weight distribution.
 
...On top of which, a 50/50 weighyt distribution wouldn't be optimal for a FWD car anyway.
 
Originally Posted By: rshunter
I really, really liked the '92 and '93 Acura Vigor. It was a highly under-rated automobile and a stunning car in a black/black color combo. They had a beautiful leather interior, that lovely inline-5 engine and a great 5-speed manual gearbox. I had the opportunity to spend time with just such a car and I still have fond memories of it. Of all the cars I had the opportunity to work with, the Vigor is one of the few that I would have bought without hesitation.


I was going to mention the Vigor, but Silk beat me to it. My buddy has a '92 with almost 200k miles. It's a great car as long as you don't need to carry four adult males. Ride, handling, and the controls are all very refined. The interior is high quality and his cloth seats are very comfortable and durable, but even I can't comfortably fit behind myself, and I'm only 5'10". They sacrificed a lot of interior space for that beautiful long hood!
 
The Cord has a longitudinal engine and the old GM vehicles mentioned do as well. Although the Cord would count as FM certainly. My thinking was it doesn't seem like it would be *that* different to mount a transverse engine behind the axle vs in front. Maybe it doesn't actually have any advantage or maybe the packaging compromises aren't worth it.

The Vigor does seem like a really interesting car.

I figure there must be *some* reason because even when Honda and Mitsubishi were mounting their transverse engines on the drivers side instead of the passenger side, the engines were still in front of the axle in all cases AFAIK.
 
Originally Posted By: rationull
The Cord has a longitudinal engine and the old GM vehicles mentioned do as well. Although the Cord would count as FM certainly. My thinking was it doesn't seem like it would be *that* different to mount a transverse engine behind the axle vs in front. Maybe it doesn't actually have any advantage or maybe the packaging compromises aren't worth it.


Mounting the transverse engine behind the axle line probably wouldn't change the weight distribution much. And like you mentioned, it would be a packaging problem. You want the axle and suspension mounts as close to the firewall as possible for efficient packaging and chassis rigidity and weight reduction, crumple zone etc. Moving the engine back could impede on the rear mounted rack and pinion and stabilizer bar.
Sometimes you'll see a 4 cylinder sloped rearward. This is mostly for a lower hood line but also probably shifts some weight rearward and lowers the engines center of gravity some, and without impeding on the steering rack and stabilizer.

Quote:
I figure there must be *some* reason because even when Honda and Mitsubishi were mounting their transverse engines on the drivers side instead of the passenger side, the engines were still in front of the axle in all cases AFAIK.


As you mentioned the engine was still mounted forward for the reasons above. One thing about mounting the engine on the left side is the driver side is on the right hand side in these cars' domestic market.
 
Yes,most of the French cars had the gearbox in front of the engine,starting with the Light Fifteen or Traction Avant,and they were still doing it into the '80's.I don't remember any problems with interior space.
 
No space problems at all.
Two adults and a teenager in the front of the R-16 has no problem...no trans tunnel to straddle.
 
Originally Posted By: mechanicx
Sometimes you'll see a 4 cylinder sloped rearward. This is mostly for a lower hood line but also probably shifts some weight rearward and lowers the engines center of gravity some, and without impeding on the steering rack and stabilizer.

You've described my Mk3 Honda Prelude to a tee. I'd love to see the shoehorn they used at the assembly plant to get the powertrain into the thing. To say it's a tight fit would be one of the World's greatest understatements.
 
Originally Posted By: carwreck

1930's DKW F5. Transverse FWD mounted behind the front axle.
Notice the space saving gas tank mounted behind the engine, above the footwell.

http://douging.smugmug.com/Cars/Boston-a...05_9YpcM/Medium

http://douging.smugmug.com/Cars/Boston-a...86_z8SNh/Medium


Hah, so it has been done!


I didn't realize there were so many cars using longitudinal FM FWD designs out of France. Looking at pics of those cars it's interesting to see the small front overhangs they managed with that setup.
 
My Corolla's and Camry's 4-cylinder engines also have a rake to them. The ZZ engine in the Corolla was at least 15 degrees rearward. I'm not sure on the AR engine in the Camry, but it leans also. Yeah, the rear-mounted rack and pinion would be an issue. You could mount it forward of the axle, and get an advantageous "front turning" setup (vs. rear turning as most FWD vehicles are), but I'm not sure how they'd run the steering shaft passed the transmission.
 
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