I used to run the mcmaster type nozzles with my old kit and judging from testing them out of the car the ones that snow uses atomize better (especially the 15GPH mcmaster type...that thing was pretty bad).
Snow nozzles are rated at 60 psi.
FYI, Snow is notoriously conservative with nozzle size/flow rate. I get the impression they think us monkeys can't tune so they sell us small nozzles that are easy to tune thru.
I'm not monitoring my pressure. No need. I have a wideband staring me in the face. If the pressure takes a dive I'll see the AFR's suffer. Shurflo pumps are adjustable. When you get the 220 psi pump out of the box its set below 220 (for ?warranty? reasons or something like that) and you need to turn the allen wrench adjustment thru the roof to peg it out. That and hotwire the pump motor so the pressure switch isn't in the circuit (and it never throttles back).
How does it cool better than gas you ask? This is easier to steal off the net than to type out...keep in mind when you read this that you have to inject ALOT more Methanol than gas to get the same AFR.
Quote:
Closely related to volatility is a quality called "latent heat of vaporization". When a liquid is at its boiling point, a certain amount of additional heat is needed to change the liquid to a gas. This additional heat is the latent heat of vaporization, expressed in Btu/lb in Figure 2-2. This effect is one of the principles behind refrigeration and the reason that water evaporating from your skin feels cool.
Referring to Figure 2-2, gasoline has a latent heat of about 140 Btu/lb; methanol, 474 Btu/lb; and ethanol, 361 Btu/lb. In an engine, vaporization of the gasoline fuel/air mixture results in a temperature drop of about 40 degrees Fahrenheit. Under similar conditions, the temperature drop for ethyl alcohol will be more than twice that of gasoline, and for methanol the drop will be over three times as great. These temperature drops result in a considerably greater "mass density" of the fuel entering the engine for alcohol as compared to gasoline. The result is a greatly increased efficiency for alcohol fuels. To visualize why, remember that at a given pressure, the amount of space a gas occupies is directly proportional to the temperature. For example, if one pound of a gas fits into a certain container at a given pressure and the temperature is cut in half, the container will now hold two pounds of the gas at the same pressure. In an engine, a stoichiometric mixture of methanol and air would be over three times colder than the same gasoline/air mixture. This means that there is now over three times (by weight) as much methanol in the cylinder. Now, even though methanol has only half the heat value of gasoline, the net gain in "volumetric mass efficiency" is over three times. So, for example, if the gasoline/air mixture in a given engine cylinder produces 100 Btu on each stroke, the same engine would produce 150 Btu per stroke with methanol. This power gain due to increased volumetric mass efficiency is the primary reason for the popularity of methyl alcohol as a racing fuel. With ethanol the effect isn't quite as dramatic, but the greater heat value partially offsets the lower latent heat. Overall, this power increase with alcohol fuels considerably mitigates the liability of low heat value.
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