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Civvy
04-10-2005, 12:06 PM
Been thinking the last couple of days bout this and i havent managed to figure it out for myself so thought id ask.

Our engine firing order is 1-3-4-2. Which to me means (imagining piston 4 is in the same position as piston 1), when cyl 1 fires, cyl 4 isnt on its power stroke and therefore ONLY piston 1 is turning the full engine ( and the other 3 pistons at that given time).

Now. Question is, why didnt they design both pistons (two at a given time) 1 & 4 & 2 & 3 to fire together thus doubling the power of the engine???????

Forget the ignition & cams for now.

MrBen
04-10-2005, 12:53 PM
Second question, why is this in Off Topic? :huh:

Moved to General

AccordNut
04-10-2005, 01:02 PM
i thought it was 4-2-1-3? coulda sworn it was that order

ICEMAN707
04-10-2005, 01:08 PM
Been thinking the last couple of days bout this and i havent managed to figure it out for myself so thought id ask.

Our engine firing order is 1-3-4-2. Which to me means (imagining piston 4 is in the same position as piston 1), when cyl 1 fires, cyl 4 isnt on its power stroke and therefore ONLY piston 1 is turning the full engine ( and the other 3 pistons at that given time).

Now. Question is, why didnt they design both pistons (two at a given time) 1 & 4 & 2 & 3 to fire together thus doubling the power of the engine???????

Forget the ignition & cams for now.

i think it has to do with cams and ignition, but like you said, forget that. but the reason for that mainly is, the a20 isn't meant to be a high power, gas guzzling engine. i mean, your theory could be possible if the cams and ignition timing were according to that, but honda didn't design the a20 to be a race engine. instead, just a 30 mpg economy engine. in a way it's the same principle as honda's newer v6 engines, where it runs on 6 cyl at acceleration but cuts down to 3 cyl at cruising speed by shutting off ignition and fuel to the other 3 cylinders.

carotman
04-10-2005, 01:23 PM
This is a 4 stroke engine... if 2 pistons fired at the same time, you would basicaly end with an engine that doesn't fire half of the time.... With the 1-3-4-2, you get an explosion on every engine revolution. This gives a smoother engine

Reptile
04-10-2005, 02:08 PM
Wow, that is a good question.

'89AccordLX(Rus)
04-10-2005, 02:47 PM
I agree with Carotman here, in addition, even if one could design a four cylinder engine that would have combustion in two chambers simulataneously, the engine would need a heavy flywheel to carry it through to the next combustion cycle. Furthermore, if you think about it, producing power on every second revolution instead of every revolution would probably cut down on power output (torque).

BlueBead
04-10-2005, 05:37 PM
This is a 4 stroke engine... if 2 pistons fired at the same time, you would basicaly end with an engine that doesn't fire half of the time.... With the 1-3-4-2, you get an explosion on every engine revolution. This gives a smoother engine
werd... its called a two stroke and is otherwise known as a weedeater....lol

gp02a0083
04-10-2005, 07:06 PM
nah called a rotery engine lol contunious powerstroke lol well kinda

Civvy
04-11-2005, 02:50 AM
89 accord... Furthermore, if you think about it, producing power on every second revolution instead of every revolution would probably cut down on power output (torque).[/QUOTE]

So we would design it with a short stroke.
I'm beginning to think this is a two stroke engine, so then why not have a shorter stroke and use 4 cylinders? Thought two stroke bikes were quicker than four strokes in the olden days?
So, if we were to have 8 cylingers and make up the same cc. and we had two pistons at a given time on the power stroke we would gain more rite? ...because two seperate explosions would be better than one? no. nevermind. :uh:

Vanilla Sky
04-11-2005, 03:06 AM
one reason two cylinders don't fire at once is because of the severe shock it would cause... don't expect that engine to last...

and this is a 4 stroke motor... intake, compression, power, exhaust... takes 4 strokes to complete the cycle...

on a 2 cycle, there are 2 strokes to each cycle... http://science.howstuffworks.com/two-stroke2.htm explains this better

with a 4 cyl motor with 2 cylinders firing at the same time, you would essentially have a 2 cyl motor...

no matter how many cyliners a 4 stroke gasoline motor has, it has sequential firing, not simutaneous like you've described in your question

Oldblueaccord
04-11-2005, 12:46 PM
Thats why V-8 have an advantage they almost have 2 cylinders firing at the same time very close in fact. So there smother and more balanced motor.

Just a guess is why you dont see to many 4 cylinders over 2.2 -2.4 liters.

Very good observation BTW civvy.

wp

Strugglebucket
04-11-2005, 05:16 PM
i thought it was 4-2-1-3? coulda sworn it was that order
same thing as 1-3-4-2.