What's your answer to this question??

[lineslinger]

Originally Posted by Naumoff

The answer is three.

And cold doesn't exist. It is only the absents of heat/energy.

Tony, I'm with you on "cold", but..
Are you telling me that the downstroke of the piston doesn't create a vacuum? That no suction is present?
That with the sudden drop of the piston there is no reactive effect to fill the void that is created?
The intake valve does not open at the bottom of the stroke, it opens before the bottom of the stroke.

[Naumoff]

Originally Posted by lineslinger

Tony, I'm with you on "cold", but..
Are you telling me that the downstroke of the piston doesn't create a vacuum? That no suction is present?
That with the sudden drop of the piston there is no reactive effect to fill the void that is created?
The intake valve does not open at the bottom of the stroke, it opens before the bottom of the stroke.

At sea level there is atmospheric pressure or psia(absolute) of 14.7.
When you see a Gage reading zero that is not true pressure that is Gage pressure. There is pressure pushing down on everything all the time.

The air/fuel mixture needs time to move into the cylinder. Opening on the down stroke gives it time to move in nice and smooth. As the piston goes down it does not let the air underneath it fill the cylinder so the valve opening lets the pressure in the top of the carburetor go through it and into the cylinder.
Nature is only trying to maintain balance.

Water seeks its own level.
Stick your finger over a straw and plunge it into a glass of water. What happens? the water does not go up the straw. Why? Are you pushing pressure in the straw or are you pulling a vacuum on the top of the glass?
If I haven't confused you enough keep asking question. I will get you there sooner or later.