The key to proper heat transfer is to allow the coolant to just enter the nucleate stage when the engine is under severe or heavy load. Then have the system pressure move the boiling coolant away from the site, taking the heat along with it, and recondense back to a liquid as it is pushed away. This cycle of heating, nucleate boiling, release from the site, and recondensing goes on continually in the cylinder heads’ water jackets and is responsible for the consumption of the chemical-additive package that is included in traditional engine coolant. This is why anti-freeze wears out and needs to be changed.

Products that are designed as an engine coolant include anti-corrosion inhibitors along with elements to make it more slippery. This is represented using a metric of dymes/centimeter. It is a measure of the surface tension of the coolant. The lower the surface tension the liquid has, the easier it will release from the water jacket casting in the cylinder when nucleate boiling occurs. It can then recondense and remove the necessary heat. A liquid that likes to cling may have the ability to absorb heat but will negate that benefit by refusing to leave the nucleate boiling site. It will then enter crisis boiling and become worthless as a coolant.

For many years it was believed that water was the best engine coolant since it has a specific heat rating of one, but it is a poor choice. Even if you do not consider the corrosion it causes, the low boiling point even when used with a radiator cap, and the high surface tension means that it will not do an effective job of removing heat from the cylinder head when compared to an application-specific engine coolant, no matter what the dashboard gauge states.

Advanced Chemistry

While other areas of engine technology have dramatically improved in the last decade, engine coolant (usually a mixture of ethylene glycol and water in a 50/50 solution) has remained the standard. There is no denying that traditional water-based coolant worked—there are not cars overheated all over the road—but a better chemistry was needed for engines to become more efficient and to address environmental concerns.

Here’s the analogy: The old bias-ply tire held air and got the vehicle down the road, but it cannot be compared to the performance, wear, and overall improvement of a modern radial. Just think of the Evans NPG-C coolant as a modern radial tire and traditional water-based anti-freeze as a bias-ply design.

Evans NPG-C gets it name from being a non-aqueous glycol that has no water mixed with it. A side benefit of the elimination of the water from the chemistry means that corrosion and cavitation in the cooling system and engine is completely eliminated, and there are no additives that deplete. The Evans NPG-C is a lifetime coolant.

The real benefit of this modern chemistry is that it does not boil until 375 degrees F, virtually eliminating any chance of overheating in the radiator. This high boiling point is responsible for a drastic drop in the metal-surface temperature of the combustion chamber in the cylinder head over traditional water-based coolant. Since it will refrain from boiling, more heat transfer occurs.

Once the coolant enters the nucleate stage, the fact that it has a much lower surface tension as measured in dynes/centimeter (it is more slippery) means it releases from the water jacket with less system pressure and allows fresh coolant to come in contact with the region. Thanks to Evans NPG-C unique chemistry, the system operating pressure is lower since it does not expand at the same rate as conventional coolants nor does it ever freeze. All of these attributes allow for a more aggressive fuel mixture and ignition curve (or boost pressure) since heat-induced detonation will be eliminated in performance use.

When Evans NPG-C is employed in a passenger car or heavy-duty application, it will promote increased longevity for the engine and its components, the ability to use lower octane fuel, and reduced maintenance costs.

To convert from traditional coolant to the Evans NPG-C, all that is required is the complete removal of the old coolant and a refill with the Evans product. The Evans website goes over the procedure in great detail.

For those who want the most from their engines, it is this author’s opinion that the choice is clear. Get the water out and pour in the Evans!

Evans Cooling Systems
255 Route 41 North
CT  06069