Honda 2.4 inverted mounted engine.....

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I know in my 7th generation Accord, the engine (K24) is mounted "backward" from the usual layout. I have wondered, why did Honda choose to do this? Do other car companies do this, and what benefit is there, if any? Also, is the engine truely mounted backward, or is the engine engineered to "spin" the opposite way. Which begs the question...does the crank spin toward me, or away. I was just watching a review of the 2013 Accord and it looks like the 2.4 in it is mounted like other 4 bangers. This is all for curiosity sake of course.
 
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Old Honda engines spun backwards - it's what happens when you evolve from motorcycles to cars. They then started building engines that spun the normal direction because they wanted to sell engines to other manufactures (like the V6 in the Saturn SUV)... I have no idea what the current state is.
 
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Inverted? That's upside down. Honda and Mitsubishi had their engines mounted on the left side of the car, possibly because in a righthand drive car it makes for easier mounting of brake and steering controls. Mitsubishi added and extra idler gear to get the correct rotation of the drive...Honda ran the engine anticlockwise. Mitsubishi changed to a righthand engine mounting in about 1995 - park a 1994 and 1995 Diamante side by side and they are a mirror image of each other. Honda made new engines and driveline when they flipped over.
 
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Originally Posted By: Skid
Old Honda engines spun backwards - it's what happens when you evolve from motorcycles to cars.
So motorcycle engines spin backwards ? Which side of the bike are you standing when you see that?
 

gregk24

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Your right, guess I should say...backwards mounted engine. Either way, does anyone know if the 7th gens had there enigne mounted backward, or they were designed to "spin" backward when compared to other car makes.
 
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Yes, your k24 is backwards as in the exhaust is near the firewall and the intake is in front near the radiator. No, this is pretty uncommon for transverse 4 cylinder engines. It was new, the F23 before it was the normal layout. When they did this is was in the press release but I don't remember why. So no, the 7th gen had the exhaust near the radiator like most cars. I really doubt it matters much, a little less cooling and a little shorter exhaust. It's no different than the rear bank of a transverse v6.
 
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gregk24

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Originally Posted By: bepperb
Yes, your k24 is backwards as in the exhaust is near the firewall and the intake is in front near the radiator. No, this is pretty uncommon for transverse 4 cylinder engines. It was new, the F23 before it was the normal layout. When they did this is was in the press release but I don't remember why. So no, the 7th gen had the exhaust near the radiator like most cars. I really doubt it matters much, a little less cooling and a little shorter exhaust. It's no different than the rear bank of a transverse v6.
What? You said it both ways? Mine is the 7th gen 2.4.
 
Originally Posted By: bepperb
Yes, your k24 is backwards as in the exhaust is near the firewall and the intake is in front near the radiator.
The position of the intake and exhaust has nothing to do with what the OP is describing. My mazda 3 has the exhaust in the back, which is pretty common nowadays as it allows for the cat converter to be close to the exhaust manifold/ header. What OP is referring to is that the early Honda models had the transmission positioned on the passenger side, where the conventional way is to have the tranny on the drivers side. I think the crank rotation was still clockwise, but I'm not sure.
 
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In Europe since 2000 engines are mounted in standard way at least on Civic. In past they mounted them in oposite way since they are right hand market primarily. Today they sell large number of cars in NA and Europe so they adopted more usual way of mounting engine. On my 93 Civic Vti ABS unit was on the oposite side of master brake cylinder simply because there was no room for it. And for last 15 years crash test are more stringent so that overlap collision is probably easier to meet with small gearbox in front of the driver.
 
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The original claimed reasons usually revolved around getting the exhaust manifold as close to the catalytic converter as possible, for quicker light-off after a cold start. Putting the exhaust at the rear of the engine better facilitated that. I personally prefer this layout, as the exhaust manifold typically requires little-to-no servicing during the life of the vehicle, and it's packed away in the rear where it's out of the way. The intake manifold, however, sometimes has butterflies that may need servicing or PCV or breather valves that sometimes need servicing, and it makes sense to have these in the front of the engine. Now that exhaust manifolds are commonly integrated into the cylinder head, and catalytic converters are smaller and bolted straight to what is essentially an enlarged cylinder head, it's more common to see the exhaust on the radiator side of a transverse engine. I still don't like that. Related anecdote: My 2011 Camry's AR-series engine had the exhaust on the radiator side and the intake on the firewall side. Guess how long it takes to replace the PCV valve on that engine. It's a 4-6 hour job (by the book) and requires complete removal of the entire intake system. There may be noise benefits to putting the exhaust at the front. Not worth it to me, though.
 

gregk24

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Originally Posted By: Hokiefyd
The original claimed reasons usually revolved around getting the exhaust manifold as close to the catalytic converter as possible, for quicker light-off after a cold start. Putting the exhaust at the rear of the engine better facilitated that. I personally prefer this layout, as the exhaust manifold typically requires little-to-no servicing during the life of the vehicle, and it's packed away in the rear where it's out of the way. The intake manifold, however, sometimes has butterflies that may need servicing or PCV or breather valves that sometimes need servicing, and it makes sense to have these in the front of the engine. Now that exhaust manifolds are commonly integrated into the cylinder head, and catalytic converters are smaller and bolted straight to what is essentially an enlarged cylinder head, it's more common to see the exhaust on the radiator side of a transverse engine. I still don't like that. Related anecdote: My 2011 Camry's AR-series engine had the exhaust on the radiator side and the intake on the firewall side. Guess how long it takes to replace the PCV valve on that engine. It's a 4-6 hour job (by the book) and requires complete removal of the entire intake system. There may be noise benefits to putting the exhaust at the front. Not worth it to me, though.
Wow, thats a pain. I was able to replace my PCV in about 5 minutes.
 
Yup, count me in as well for not liking the exhaust on the radiator side. Here in the rust capital of Canada it can present a host of other problems. Simple pan drops or changing the rusted oil pans can be a major work due to the exhaust routing, not only because you have to remove the exhaust, but a lot of times it's severely rusted as well.
 
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Are we discuss here of engine head crossflow direction or the way that engine/gearbox assembly is positioned in car engine bay? I thought it was second.
 
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I'm speaking with my North American bias here. My thought on this Honda "Backwards" engine issue has to do with the layout of the engine and transaxle. If you compare Honda to other FWD cars in NA, you'll see Honda placed the engine on our drivers side. Most others place the engine on the passenger side. I suspect this is because of the Japanese origin where the drivers side of the car there is the RHS. Here in NA, the drivers side is the LHS. Makes sense from a balance perspective if you live in Japan. If the driver is on the RHS, put the mass of the engine on the LHS for better side to side balance. Now the question is, does the engine need to rotate the other direction if the layout of the engine/transaxle goes L to R instead of the more common R to L for NA cars? Honda: Mazda Protege:
 

gregk24

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Originally Posted By: javacontour
I'm speaking with my North American bias here. My thought on this Honda "Backwards" engine issue has to do with the layout of the engine and transaxle. If you compare Honda to other FWD cars in NA, you'll see Honda placed the engine on our drivers side. Most others place the engine on the passenger side. I suspect this is because of the Japanese origin where the drivers side of the car there is the RHS. Here in NA, the drivers side is the LHS. Makes sense from a balance perspective if you live in Japan. If the driver is on the RHS, put the mass of the engine on the LHS for better side to side balance. Now the question is, does the engine need to rotate the other direction if the layout of the engine/transaxle goes L to R instead of the more common R to L for NA cars? Honda: Mazda Protege:
Well the 7th gen Accord is set up with the engine on the passenger side with the intake facing forward like that Mazda.
 

gregk24

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Now that I look at some pics of the older civics, I see that the intake is mounted on the front, yet the engine is on the drivers side, yet the Accord K series has the intake on the front, and is mounted on the left side.
 
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At least with a manual transmission the engine would need to turn in the same direction as the wheels to minimise the gearsets required. The transmission reverses the engine direction, then the final drive reverses it again, back to the same as the engine.
 
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Originally Posted By: gregk24
Now that I look at some pics of the older civics, I see that the intake is mounted on the front, yet the engine is on the drivers side, yet the Accord K series has the intake on the front, and is mounted on the left side.
Position of intake/exhaust have nothig with way engine is mounted in car. On crossflow head manufacturer can put intake in front or back. Usually exhaust is in front on a FWD car to reduce noise in car and heat in engine bay. There is also more room for manifold mounted cat.
 
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Originally Posted By: KrisZ
older engines could be bump started spinning the opposite of normal operation. Though it's not likely anymore. It's purely up to the engineers which way the crankshaft spins.
Only two strokes and old direct reverse diesels using a sliding camshaft with forward and reverse lobes. A four stoke will not run with the exhaust stroke preceding the compression stroke.
 
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