Carb sreens; a different theory of vaporisation

O.k., stop beating your head against the wall.I should have said 'enough of a restriction to seriously effect driveability, etc'.

And I take your point re: overcarbing as well. I guess what I was asking, is if you had a carb that was "just big enough", like the stock 1 bbl. and you put a screen in it, it might be enough of a restriction to adversely affect performance. If you put a larger carb on it, would that tend to correct that problem.Seems like it would.On these engines that came with a 1 bbl stock, people are putting 2 and 3 1bbls on them, so obviously the engine can take a lot more than Ford was giving them.Different intakes, of course, and theyre not improving the mileage!

On the 'hot spot', thats exactly where I intend to put the air diverter, thats going to (hopefully) turn the a/f mix 90 degrees, just before it hits the screens.Actually, thats something else I'm not clear on;On the 215's and 223's, the 'hot spot' was sufficient. On the 262's, they had problems with carb icing, and had to add a coolant heated carb spacer.It is said that when gas vaporises, it "Gets cold", and you can certainly feel it, with gas on your skin.And yet thermodynamics says thats crap.Heat, like light, is energy.Cold is the absence of energy, just as dark is.On the other hand, if someone turns out the lights, it sure seems like it "gets dark". So, what is happening, acording to thermodynamics.Is the gas, on vaporising, 'shedding' the heat in it, or is it that because its vaporising, its expanding, and can therefore absorb more heat, or what."Heat is energy, and only heat can move, not cold". Anyway, been wondering about that for some time. :unsure:
 
Divco man":2xw200xf said:
.... if you had a carb that was "just big enough", like the stock 1 bbl. and you put a screen in it, it might be enough of a restriction to adversely affect performance....

Yup. The stock Carter YF will feed a stock 300 up to about 3000 rpm, after that even a bone stock 300 will make more power with a bigger carb.

The theory of vaporization is properly studied as refrigeration; this is what makes your air conditioner work. When a liguid changes state into a gas, it uses a certain amount of energy (heat) that appears to be lost in the process. This is known as the "latent (hidden) heat of evaporation". The heat is taken from one source (your skin when you pour gasoline on it) and is transferred to the evaporated substance. You could Google it or try Wikipedia for a better description, but that is the gist of it.

Having driven old trucks, etc. I can tell you that they indeed had problems with carb icing. Folks just got tired of it and the engineers finally designed stuff to correct it. Heated air into the carb does FAR more for controlling icing than does the hot spot manifold. Think about it; the carb is ABOVE the hot spot, far, far away from the venturi that creates the pressure drop which causes the icing. The hot spot doesn't do anything until long after the fact. My 81 F-150 has the proper stock manifolds and it had serious icing problems until I got the air cleaner completely back to correct function of ALL the hot air equipment (removed by a previous owner).
Joe
 
Back
Top