Horizontal cylinder advantages
Horizontal cylinder advantages
Author
Discussion

windtalker

Original Poster:

3 posts

221 months

Monday 23rd April 2007
quotequote all
Hello all..
Well id like to know what advantages there could be for a cylinder reciprocating in the horizontal plane.

If we were to take a normal 4 cylinder inline engine and rotate it by 90 degrees so that the piston reciprocates in the horizontal direction,would there be any savings in power(that is frictional power)??

Thanks

MTv Dave

2,101 posts

273 months

Monday 23rd April 2007
quotequote all
I'd have thought there'd be problems with wear on the lower half of the cylinder, leading to possible leaks on the top half, but I expect if an engine designer chose that route, they could accomodate that.

Not sure about any beinifits, other than from a packaging point of view with the small possibility of getting the bonnet line lower (maybe even higher with ancillaries attached), just problems...

windtalker

Original Poster:

3 posts

221 months

Monday 23rd April 2007
quotequote all
what about from balancing point of view?
wont the flywheel mass reduce since it does not have to take care of vertical motion of piston?

munter

31,330 posts

258 months

Monday 23rd April 2007
quotequote all
I think you'd have all sorts of problems taking a vertical inline 4 and trying to run it horizontally. However boxer 4's are horizontal and they seem to work ok having ben designed to do it.

windtalker

Original Poster:

3 posts

221 months

Monday 23rd April 2007
quotequote all
well yeah..but still would it result in any frictional power reduction if you were to run a motoring test on it?

Buzz word

2,028 posts

226 months

Monday 23rd April 2007
quotequote all
As far as im aware the only advantages for different cylinder orientations are packaging related or to do with CoG.
With the boxer design the CoG will be lower as the engine isnt standing up. If that is worthwhile is another question as it could give you issues working on it.
The reason the boxer would have cylinders to the left and right is to balance the engine. in a normal I4 two pistons are at TDC when two are at BDC so any inertia impact can be balanced. this is never going to pan out perfectly and some use balancer shafts to overcome other planes of vibration. My main concern with running an I4 sideways would mainly be an issue like that. the inertial would not be balanced around the crank instead it would be all on one side. there could also be issues with things like low pressure oil drain and oil pickup as the parts wont be in the right place. i think if you want a flat engine it would be best to buy one.

wildoliver

9,172 posts

233 months

Monday 23rd April 2007
quotequote all
there is one engine at least that has all the cylinders to one side, the fiat 126 motor.

Not the nicest!

tribbles

4,101 posts

239 months

Monday 23rd April 2007
quotequote all
I think one of the biggest problems with getting a standard engine and turning it is the oil - it's designed to be at the bottom because that's where gravity pulls it - the pump would be sucking it in mid-air if you'd turned it too much. Plus the cylinders would be filling up with oil.

As said, use an engine already designed for it (VW Beetle is one of the more obvious choices, as well as Porsche).

Mr2Mike

20,143 posts

272 months

Monday 23rd April 2007
quotequote all
It would make absolutely no difference to balance whatever angle the engine is run at. All forces are constrained within the engine block, it can't magically get better or worse simply by tipping it on it's side.

The effect of gravity on the pistons in a horizontal configuration is negligible to the thrust they experience on compression and power strokes, so it's most unlikely that this by itself would cause more wear.

grahambell

2,720 posts

292 months

Tuesday 24th April 2007
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Agree with Mr2Mike. If you have the cylinders horizontal you'll still have the same friction to deal with and the engine's internals will still have the same inertia and still require the same size flywheel.

Only advantage - as already posted - would be lower engine/bonnet height. Mercedes 300SLR had engine canted at 50 degrees for that reason.

There was also one front-engined Indianapolis racer that did have the engine 'on its side' though the main reason for that was to run the drive shaft down one side of the cockpit rather than down the centre. Meant they could sit the driver lower, giving lower frontal area.

Pigeon

18,535 posts

263 months

Wednesday 25th April 2007
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Someone wanted me to look at the tappets on a Shitroen van once. I neshed out when I discovered that its inline four was laid more or less flat on its side on top of the gearbox, with the rocker cover hard against the bulkhead.

Mr2Mike

20,143 posts

272 months

Thursday 26th April 2007
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Pigeon said:
Someone wanted me to look at the tappets on a Shitroen van once. I neshed out when I discovered that its inline four was laid more or less flat on its side on top of the gearbox, with the rocker cover hard against the bulkhead.


Some of the earlier Peugeots (e.g. 104) were like this, major PITA to get access to do the valve clearances as you note.

chuntington101

5,733 posts

253 months

Thursday 26th April 2007
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just flicking through some WW2 aircraft stuff. found that some of the german engines where like upside down V12s! and one engine used in a bomber was two of these strapped together!

anyway back to topic.

Marquis_Rex

7,377 posts

256 months

Friday 27th April 2007
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Interesting to note that the 996 Turbo Porsches have a dowled compression ring in the piston.
I think this is to reduce the likelihood of all the piston ring gaps lining up and getting blue smoke on start up.
I've heard it can be common for Boxer motors to scrape oil into the combustion chamber initially, when left standing a while.
That said, I've never had any problems with my 993 and my father never had any problems with his VW Beetle.