Quote:
Originally Posted by Muscle Master
Hmm..... I had a dream last night, it was a X-ray view of a 4 banger but it was odd, I notice there was another cylinder and it was a little bigger than the other 4
Maybe this is a sign that I should build an engine like this
Is it possible to build an ( example of what I am talking about) 5 cylinder engine, but have a the 5th cylinder larger than the other 4 and it is only activated when the engine needs more power, kind of like AFM but....not
And here another question, how come automakers don't use cylinders with an odd number, like V3, V7, V9, V11, etc
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ooooooooooooooooooooh, this is a good one. believe it or not ive thought about this before. and discussed it seriously with a couple engineers i work with.
Quote:
Originally Posted by Shadowsong
Could always go with an inline, or a flat, or a straight 3/5/7/9
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inline would be the best bet to deal with the balance issue
Quote:
Originally Posted by Wm Holden
I think the real revolution could be in "5" strokes instead of 4..
inject water into the cyl on the 5th stroke and utilize the energy that is usually wasted as heat in the radiator....it's been done by a guy who build cams for hi po engines...and it works and the engine never gets to hot to lay your hand on it.
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6 stroke motors are in work as well:
http://en.wikipedia.org/wiki/Six_stroke_engine
and flat engines are also a good viable option for this setup:
http://en.wikipedia.org/wiki/Flat_engine
Quote:
Originally Posted by DGthe3
well, I suppose its just as hard to get it to eactly 90.000 degrees apart as it is to get it to 102.857 . . .
And I can't imagine any sort of V configuration working with an odd number of cylinders. Inline makes sense, and I remeber hearing about 7 and 9 cylinder radials from 1930's era aircraft
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you could do it, but you'd have to cheat using the design from the pic in post 14. you would technically only have 3 pistons, but one would be oval and would offset the balance.
Quote:
Originally Posted by Muscle Master
Thoses are good canidates but been done before, I also want this 5 cylinder to get 30+ MPG with a kick
the only hard part about making this engine, that is the engine architect it self, this is going to get complicated my brain hurts
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its not difficult to imagine it to look at, but the inner workings are crazy to think about. the problem of balancing is not that difficult to overcome with weights on the crankshaft. and even the power that is given by that particular piston during the combustion cycle would not be too hard to overcome. the real problem would be driveability in a motor. everytime that larger cylinder fires, you are going to get a surge in torque. for those of you out there who have a car with a large cam and an auto without a stall converter can attest to the surging you get when you are at a stop. however, this could be overcome by limiting the length of the stroke that the larger piston has.
by limiting the stroke, you are also limiting the power you are wanting to gain by doing this type of setup but it wont be a large loss. however, you will still get a lot more down-low torque. which if you work in AFM with this, and have that cyl deactivated during idle and during cruising, it could be a phenomenal motor. you would get your down-low torque to get the vehicle moving from a stop (which is beneficial to fuel economy, being able to keep the rpms low while still being in your powerband) then deactivate it when cruising with AFM to keep fuel down again, however, it would be the opposite of AFM at idle, as you would more than likely not want the large cyl firing at idle causing surging. however, it is possible... im adding a quick illustration that i made in MSpaint for everyone to imagine this.