Evans NPG+ coolant
04-24-2011, 10:04 PM
#3
04-25-2011, 04:58 PM
#4
Le Mans Master
Thread Starter
I made the investment in this stuff based off word of mouth prior to my own research.... shame on me. 
So I did the conversation as Evan's specifies and am now seeing 225deg in 80deg weather in stop-n-go traffic where before I'd see maybe 205deg on a bad day.
Car definately warms up faster than before and under some hard pulls the car heated up faster than the norm to my surprise.
Once back at a steady cruise temps would drop to the 190-194 range where I normally was @180deg.
The reason I went with this fluid was for the additional protection under hard pulls not because of "avg" driving coolant concerns.
Anyone else think I should just go back to my old mix or is there still some "protection" qualities in this stuff one would want on a hot summer DE day?
So I did the conversation as Evan's specifies and am now seeing 225deg in 80deg weather in stop-n-go traffic where before I'd see maybe 205deg on a bad day.
Car definately warms up faster than before and under some hard pulls the car heated up faster than the norm to my surprise.
Once back at a steady cruise temps would drop to the 190-194 range where I normally was @180deg.
The reason I went with this fluid was for the additional protection under hard pulls not because of "avg" driving coolant concerns.
Anyone else think I should just go back to my old mix or is there still some "protection" qualities in this stuff one would want on a hot summer DE day?
04-25-2011, 05:42 PM
#5
Race Director
Never heard of it. What is it??? For a mix use a very low percent of anti-freeze.
04-25-2011, 05:52 PM
#6
Le Mans Master
Thread Starter
As of now I'm a bit dissappointed I did this but hoping something can give. I know once on the track I'll be pushing the coolant system without a DeWitts or Ron Davis at my hp level so thats why I've ventured out for solutions in the coolant dept alone.
80% water + 20% prestone coolant + water wetter had my car running cooler than ever even in 30min stop-n-go traffic and some short hard pulls. My concern lies within that mix on the track for 20min sessions all wkd. I'd like to save myself the headache of overheating AGAIN this year. *Last year it was because of the EWP I had. Couldn't keep up with high hp and high revs for long.
Last edited by LEAVINU; 04-26-2011 at 12:45 AM.
04-26-2011, 05:41 PM
#8
Le Mans Master
Thread Starter
Got this back from Evans tech support today...
"...what you have to understand is how our coolant works. I do not tell anyone that by putting our coolant in you will see lower temps. How our coolants works is internally. When you have a motor running a water based coolant, the internal metal temps can turn water to steam vapors which cannot re-condense back to water fast enough to pull heat away from the metal. Since our coolant has such a high boiling point, ours stays a liquid all the time which in turn pulls more heat from internal metal. You also have to understand that most all sending units for the temp gauge is near the outlet of the manifold to the radiator. So if the coolant is pulling more heat, naturally the sending unit will see higher temps on the gauge. But you are also gauging temps of the coolant as it is leaving the motor, not whats in the block. The temps of the internal metal is 30-40 degrees cooler than what the gauge is reading."
"...what you have to understand is how our coolant works. I do not tell anyone that by putting our coolant in you will see lower temps. How our coolants works is internally. When you have a motor running a water based coolant, the internal metal temps can turn water to steam vapors which cannot re-condense back to water fast enough to pull heat away from the metal. Since our coolant has such a high boiling point, ours stays a liquid all the time which in turn pulls more heat from internal metal. You also have to understand that most all sending units for the temp gauge is near the outlet of the manifold to the radiator. So if the coolant is pulling more heat, naturally the sending unit will see higher temps on the gauge. But you are also gauging temps of the coolant as it is leaving the motor, not whats in the block. The temps of the internal metal is 30-40 degrees cooler than what the gauge is reading."
04-26-2011, 06:24 PM
#9
Got this back from Evans tech support today...
"...what you have to understand is how our coolant works. I do not tell anyone that by putting our coolant in you will see lower temps. How our coolants works is internally. When you have a motor running a water based coolant, the internal metal temps can turn water to steam vapors which cannot re-condense back to water fast enough to pull heat away from the metal. Since our coolant has such a high boiling point, ours stays a liquid all the time which in turn pulls more heat from internal metal. You also have to understand that most all sending units for the temp gauge is near the outlet of the manifold to the radiator. So if the coolant is pulling more heat, naturally the sending unit will see higher temps on the gauge. But you are also gauging temps of the coolant as it is leaving the motor, not whats in the block. The temps of the internal metal is 30-40 degrees cooler than what the gauge is reading."
"...what you have to understand is how our coolant works. I do not tell anyone that by putting our coolant in you will see lower temps. How our coolants works is internally. When you have a motor running a water based coolant, the internal metal temps can turn water to steam vapors which cannot re-condense back to water fast enough to pull heat away from the metal. Since our coolant has such a high boiling point, ours stays a liquid all the time which in turn pulls more heat from internal metal. You also have to understand that most all sending units for the temp gauge is near the outlet of the manifold to the radiator. So if the coolant is pulling more heat, naturally the sending unit will see higher temps on the gauge. But you are also gauging temps of the coolant as it is leaving the motor, not whats in the block. The temps of the internal metal is 30-40 degrees cooler than what the gauge is reading."
04-26-2011, 06:34 PM
#10
Le Mans Master
Thread Starter
He suggested using a laser temp gauge on the heads and see what it reads. I'd love to have a stock car with no cooling mods next to mine with both reading above 200deg and see what the head temps of each are. If mine show lesser than the other then I'd feel confident about his point as well.
05-03-2011, 10:51 PM
#11
Drifting
I have used their product in my 06 z06 especially for track days. It helped hold down the temps until I really blistered about 4 laps, then temps were every bit as high as previous water/antifreeze mix. Found out later I was supposed to only be using water at the track, so switched to water wetter and water, and frankly think this works from a temp standpoint just as well. The two benefits I can think of that make evans an item to consider is that it doesn't pressurize like water, so the chances of blowing a hose are minimized. The other benefit is the lack of cavitation in the system which has to be good. Just my .02 Jerry
05-04-2011, 12:45 AM
#12
Drifting
Got this back from Evans tech support today...
"...what you have to understand is how our coolant works. I do not tell anyone that by putting our coolant in you will see lower temps. How our coolants works is internally. When you have a motor running a water based coolant, the internal metal temps can turn water to steam vapors which cannot re-condense back to water fast enough to pull heat away from the metal. Since our coolant has such a high boiling point, ours stays a liquid all the time which in turn pulls more heat from internal metal. You also have to understand that most all sending units for the temp gauge is near the outlet of the manifold to the radiator. So if the coolant is pulling more heat, naturally the sending unit will see higher temps on the gauge. But you are also gauging temps of the coolant as it is leaving the motor, not whats in the block. The temps of the internal metal is 30-40 degrees cooler than what the gauge is reading."
"...what you have to understand is how our coolant works. I do not tell anyone that by putting our coolant in you will see lower temps. How our coolants works is internally. When you have a motor running a water based coolant, the internal metal temps can turn water to steam vapors which cannot re-condense back to water fast enough to pull heat away from the metal. Since our coolant has such a high boiling point, ours stays a liquid all the time which in turn pulls more heat from internal metal. You also have to understand that most all sending units for the temp gauge is near the outlet of the manifold to the radiator. So if the coolant is pulling more heat, naturally the sending unit will see higher temps on the gauge. But you are also gauging temps of the coolant as it is leaving the motor, not whats in the block. The temps of the internal metal is 30-40 degrees cooler than what the gauge is reading."
The higher operating temperature you are seeing is proably due to the products lower specific heat. You will see the same effect if you operate your cooling system with a mostly water mixture then shift to a 100% ethylene or propylene glycol cooling medium.
In high pressure steam generator applications water will exist in a liquid state beyond 700 deg F. Google ASME steam tables and see for yourself.
The best thing you can to to enhance cooling system's abilty to cool the engine without modifying your existing system is to run straight water with a additive package containing a corrosion inhibitor and a lubricant for the water pump internals.
Last edited by ipuig; 05-04-2011 at 12:54 AM.
05-04-2011, 08:50 AM
#13
Le Mans Master
Thread Starter
Ironically, the car is now running cooler than ever with a mix of Evans and water. 
The system was 100% evans but a small leak came about so in my attempt to correct the leak I had to dump a ton of evans, seal the thermo housing and refill. Well, after experiencing some odd overheating issues after the fix I got tired of paying $30/gal for evans. I called evans and asked what would happen if I went back to water and there was still some of their product in the system. He said "nothing, our product mixes with water fine but reduces our advertised boiling point benefits."
So in went about 1.5 gallons of water and I've been driving around town and beating on it ever sense. Car seems to be liking it so far. Have a small track day next month and an airstrip race this month so we'll see how it does with back to back 7k rpm runs.
The system was 100% evans but a small leak came about so in my attempt to correct the leak I had to dump a ton of evans, seal the thermo housing and refill. Well, after experiencing some odd overheating issues after the fix I got tired of paying $30/gal for evans. I called evans and asked what would happen if I went back to water and there was still some of their product in the system. He said "nothing, our product mixes with water fine but reduces our advertised boiling point benefits."
So in went about 1.5 gallons of water and I've been driving around town and beating on it ever sense. Car seems to be liking it so far. Have a small track day next month and an airstrip race this month so we'll see how it does with back to back 7k rpm runs.
