Wonder why Honda didn’t go with a flat engine in cars

turbo lover

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A flat-4 FWD layout seems more complicated than an I4. Flat-4 engines seem better suited for longitudinal installations (crankshaft pointing to the front or rear of the car). Longitudinal installation would likely require a complicated and less efficient transmission for a FWD vehicle. Also, the flat engine seems more complicated to build, with twice as many camshafts, heads, head gaskets, and so on.
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saz468

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To me, it looks like a flat engine would cost more to make/maintain
I don’t think cost would be a problem maintenance on the other hand probably best ask a subie owner
 

BABY NSX

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Some examples of flat engines
VW ,Subaru , Corvair, and a Ferrari flat 12

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Just from a LEGO perspective I made this vw engine and I’m guessing an inline four would’ve been a lot easier...I had to scrounge through A LOT of pieces. So with that in mind manufacturing costs would be kept down with increase ease of assemble and less parts.

Honda Civic 10th gen Wonder why Honda didn’t go with a flat engine in cars B098E2EF-9FE5-43B6-AF5E-709C066754AE


Honda Civic 10th gen Wonder why Honda didn’t go with a flat engine in cars FD3E4A09-4AED-4B16-AEA6-D84461807549
 

BABY NSX

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I don’t think cost would be a problem maintenance on the other hand probably best ask a subie owner
I heard on some generations of engines either valve cover or head gaskets seem to be something Subie owners need to address more frequently than non flat four engine owners. But I’m sure inline four engine owners have our own basket of troubles...:p
 
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saz468

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Just from a LEGO perspective I made this vw engine and I’m guessing an inline four would’ve been a lot easier...I had to scrounge through A LOT of pieces. So with that in mind manufacturing costs would be kept down with increase ease of assemble and less parts.

B098E2EF-9FE5-43B6-AF5E-709C066754AE.jpeg


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That’s definitely cool :thumbsup:
 


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saz468

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I heard on some generations of engines either valve cover or head gaskets seem to be something Subie owners need to address more frequently than non flat four engine owners. But I’m sure inline four engine owners have our own basket of troubles...:p
I think the earlier gold wing flat four had that same problem by 1980 I think they solved it
 
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saz468

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Love to see Honda make a sports car for the masses. CTR is a great car performance-wise... but a FWD 4-door 2+2 hatch doesn’t quite fit the bill for me. The Acura costs as much has my home.
I agree like the 2000s ?
 

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Here is one good reason why:
https://www.roadandtrack.com/car-culture/a19431845/why-front-engine-boxers-are-rare/

Today for some makers there seem to be only one way out of the flat front engine or diesel mistakes without too much egg on the face: electric.

The only advantages are purely in the car driveability area. The flat engine itself in cars at least, is a dead end.
It’s like the star configuration engine for aircraft: you wouldn’t put it in a car. Upside down cylinders and each at a different angle are engine-ering nonsense. But it makes sense in aircraft, obviously only because of its symmetry.

Do horizontal cylinders and two heads instead of one work? Yes.... but it’s disturbing for an egineer.
 
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saz468

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Yeah.... the 90s and roaring 00s were pretty ok.
Yeah I keep putting the s in the wrong spot the s2000 that like when I post or talk about the BMW 2002 l have to say the 2002 model if I don’t people are thinking year not model
 


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Here is one good reason why:
https://www.roadandtrack.com/car-culture/a19431845/why-front-engine-boxers-are-rare/

Today for some makers there seem to be only one way out of the flat front engine or diesel mistakes without too much egg on the face: electric.

The only advantages are purely in the car driveability area. The flat engine itself in cars at least, is a dead end.
It’s like a star configuration engine for aircraft: you wouldn’t put it in a car. Upside down cylinders and each at different angle are engine-ering nonsense. But it makes sense in aircraft, obviously only because of its symmetry.

Do horizontal cylinders and two heads instead of one work? Yes.... but it’s disturbing for an egineer.
Yes there are complications to this design and as it makes since in a aircraft it also makes since in a motorcycle Honda proved this in their gold wing but Subaru comes into play before Subaru became strictly AWD they where FWD And AWD was a option ( it was call 4wheel drive years ago) and Subaru AWD is still base off a FWD platform this platform has been Subarus success for many years and don’t see a change in their design. the subaru ad posted is for their 1976 line up of front wheel drive cars with the Flat four

Honda Civic 10th gen Wonder why Honda didn’t go with a flat engine in cars 58AD409A-54D1-4113-9BE0-DF17FE24FCAC
 

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I think the bigger question is why no V4's? has the benefits of size (HxLxW) & rpm(degree dependent) over both flat & inline. Its space in the engine bay stays relatively the same irrespective of orientation.

One thing that unfortunately doesn't translate from motorcycle to automobile engines are the compromises required for 2 wheels. Even tho a goldwing is a massive motorcycle, it is still dwarfed by even a small car in both mass & size. so whereas a bike engine may be of similar displacement, the engine architecture wouldn't support needing to move car levels of mass.

Now are we actually talking about flat engines or boxers? the 2 are not the same. the Ferrari listed previously isn't a boxer even though it is 180°. The crankshaft arrangement is still like a V engine.
 
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I think the bigger question is why no V4's? has the benefits of size (HxLxW) & rpm(degree dependent) over both flat & inline. Its space in the engine bay stays relatively the same irrespective of orientation.

One thing that unfortunately doesn't translate from motorcycle to automobile engines are the compromises required for 2 wheels. Even tho a goldwing is a massive motorcycle, it is still dwarfed by even a small car in both mass & size. so whereas a bike engine may be of similar displacement, the engine architecture wouldn't support needing to move car levels of mass.

Now are we actually talking about flat engines or boxers? the 2 are not the same. the Ferrari listed previously isn't a boxer even though it is 180°. The crankshaft arrangement is still like a V engine.
Actually Saab had a V4 it was in the 96 and sonnet

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saz468

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Also to add once again Honda motorcycle ST 1100 also had a V4 engine design

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Yeah I keep putting the s in the wrong spot the s2000 that like when I post or talk about the BMW 2002 l have to say the 2002 model if I don’t people are thinking year not model
I got what you said. I think the human mind can unjumble words that are misspelled or something like that.

Funny you mention those cars. locally there’s a guy with a bmw 2002 with an s2000 drivetrain in it.

When I think of the genre of “sports cars” from Honda, from the 80s/90s the Acura Legend coupes were cool. I sorta look at them as sports cars even though they are more in the luxury car genre. I used to work at an Acura dealer in the early 90s and the 1989/90 Legend coupes were cool when they had custom wheels and the early 90s Legend coupes especially in GS form were nice. Both could be had with a V6 and manual transmission. Not super fast but quick for the time. The GS only had 230hp but nice torque.

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