idea, 4 cylinder to 2 cylinder engine conversion

[BlueFoot]

I had a 2002 ford focus that somewhat frequently shot the spark plugs out. The last time it happened to me I decided to just drive home on it. I thought I was only misfiring on one cylinder but when I got home I looked at it and saw that the spark plug that shot out had pulled off the plug wire from another spark plug as well. So I was running on 2 cylinders for approximately 20 miles. Top speed I could hit was about 60 mph. Power was very lacking. It definitely runs rougher on 2 cylinders and doesn't have enough power. On 3 cylinders, when it happened previously, it actually wasn't horrible for power, I had no problem going 65, but it did run rougher than on 4. If it was done well a 3 cylinder conversion would probably work ok. 2 would really be pushing it.

I was just reading about this 2 cylinder engine that gets better mpg than my honda fit, and has only slightly less horsepower. 56 mpg and 105 HP. Green Car Congress: Fiat introducing new 2-cylinder 0.9L Turbo TwinAir in 2014 MiTo mini

[euromodder]

Originally Posted by BlueFoot

I was just reading about this 2 cylinder engine that gets better mpg than my honda fit, and has only slightly less horsepower. 56 mpg and 105 HP. Green Car Congress: Fiat introducing new 2-cylinder 0.9L Turbo TwinAir in 2014 MiTo mini

IRL the TwinAir's numbers aren't all that impressive unfortunately

[oldtamiyaphile]

I can hit 100mpg (imp) with mine and some dedication. Currently on the biggest factory alloys, I have a set of base model steelies and hubcaps ready to swap on and get a good 10mpg.

[euromodder]

Originally Posted by oldtamiyaphile

I can hit 100mpg (imp) with mine and some dedication. Currently on the biggest factory alloys, I have a set of base model steelies and hubcaps ready to swap on and get a good 10mpg.

I can hit infinite mpg - even without dedication.
Too bad it doesn't last for a full tank ...

Sorry, but your best tank average on the Twin Air is currently 50 mpg US / 60 mpg Imp
That's a LONG way off 100 mpg - US or Imp
And still 15% below EPA - let alone NEDC - consumption numbers.

[oldtamiyaphile]

Originally Posted by euromodder

I can hit infinite mpg - even without dedication.
Too bad it doesn't last for a full tank ...

Sorry, but your best tank average on the Twin Air is currently 50 mpg US / 60 mpg Imp
That's a LONG way off 100 mpg - US or Imp
And still 15% below EPA - let alone NEDC - consumption numbers.

I did 100mpg Imperial on a dedicated 'see what I can get' run over about 25km, starting and finishing at the same point so as not to be (con)descending the whole way. I even had to use the A/C a bit.

I share the driving 50% so the numbers don't tell the whole story. Quoting my signature to me is a bit daft, I'm pretty sure I've seen it. There's obviously no EPA figure for a car never sold in the US so whatever that 'let alone NEDC' comment means.. lol

If I get to just shy of the official NEDC figure, it will be in the Ecomodder top ten, so it really doesn't matter what the NEDC says, I'll have a top ten car even if I can't match those figures. The car's still only got 8000km on it, and there's a lot more to come as the car breaks in.

[Arragonis]

I could get Mrs A's Prius to 99.99 MPG regularly over 30-50 miles.

Longer or for a full tank was more of an issue.

[cRiPpLe_rOoStEr]

Originally Posted by BlueFoot

I had a 2002 ford focus that somewhat frequently shot the spark plugs out. The last time it happened to me I decided to just drive home on it. I thought I was only misfiring on one cylinder but when I got home I looked at it and saw that the spark plug that shot out had pulled off the plug wire from another spark plug as well. So I was running on 2 cylinders for approximately 20 miles. Top speed I could hit was about 60 mph. Power was very lacking. It definitely runs rougher on 2 cylinders and doesn't have enough power. On 3 cylinders, when it happened previously, it actually wasn't horrible for power, I had no problem going 65, but it did run rougher than on 4. If it was done well a 3 cylinder conversion would probably work ok. 2 would really be pushing it.

Since the Focus has a 1.6L engine available in overseas markets, including a detuned version available in Europe, a 3-cyl 1.5L would be perfectly reasonable. The lesser weight and the decrease on internal frictions from having one less cylinder would eventually compensate for the 100cc reduction.

[PremierSprinter]

Admittedly, I skipped through the whole thread, meaning this may have already been covered… but OP, you could achieve what you are trying to do without too much work.. if you have a lot of time and a little money, it would b interesting to try. Some people have mentioned that their cars lacked power pretty badly when they were missing, though they still have compression strokes and valvetrain loss being wasted.

You would be best off working with the outer two cylinders to help with vibrations and to keep cyl#1 TDC as a reference. You could strip the rods and pistons from the center cylinders but you would then need to drill the oiling holes on the crankshaft and tap them for an NPT plug. It would be a good idea to neutral balance the crankshaft after this. From there, you could pull the valves and springs on those cylinders, again drilling and tapping the holes from the valves for plugs. Take the intake and exhaust manifold gaskets and cut out steel spacers without openings for the center cylinders and then use two gaskets… You could then just unplug the injectors and coils (or wires) for the center cylinders. Without the dud compression strokes, power wouldn't be so bad and the idle would be much improved.

[PremierSprinter]

Admittedly, I skipped through the whole thread, meaning this may have already been covered… but OP, you could achieve what you are trying to do without too much work.. if you have a lot of time and a little money, it would b interesting to try. Some people have mentioned that their cars lacked power pretty badly when they were missing, though they still have compression strokes and valvetrain loss being wasted.

You would be best off working with the outer two cylinders to help with vibrations and to keep cyl#1 TDC as a reference. You could strip the rods and pistons from the center cylinders but you would then need to drill the oiling holes on the crankshaft and tap them for an NPT plug. It would be a good idea to neutral balance the crankshaft after this. From there, you could pull the valves and springs on those cylinders, again drilling and tapping the holes from the valves for plugs. Take the intake and exhaust manifold gaskets and cut out steel spacers without openings for the center cylinders and then use two gaskets… You could then just unplug the injectors and coils (or wires) for the center cylinders. Without the dud compression strokes, power wouldn't be so bad and the idle would be much improved.

[cRiPpLe_rOoStEr]

I'd rather attempt to physically remove the disabled cylinders, and for that matter a boxer engine seems to be more suitable. Many Volkswagen air-cooled engines underwent such procedure to be used in ultralight aircrafts.