Cooling: The other half of the story

[Kenny]

We are often concerned with high engine coolant temps and everyone has seen part of my cooling answer.


There is much more to the story. Most car guys use lower temp aftermarket t-stats to reduce underhood temps to improve intake charge and therefore power. We don't have to worry with that on the Raptor

The higher factory setting is for improved emissions and cylinder wall wear. We routinely run race engines near 230° as long as we can keep it stable. You lose less power to the cooling system and cylinder wall wear characteristics can be improved, but oil temps are another story, and probably more critical. Cooler oil not only helps reduce the load on the cooling system, the gains in component reliability can be astounding. One of the things we want to avoid with the coolant temps is big swings in temp, which is hard on head gaskets. We wanna keep a nice even average temp. Reducing oil temps will go a long way toward reducing spikes.   

Valvesprings are VERY sensitive to temperature and their lifespan directly correlates to operating (oil) temps. Clutches, wristpins, pin bores, piston.....basically everything in the engine will see improved lifespan. Then you have the benefit of a cooler piston that reduces the chance of detonation. There's not much reason to keep the head temps below 230° to avoid detonation when the bottom half of the combustion chamber (piston) is 300°. Your oil will also be in much better condition when you do an analysis. You can use anything from a universal power steering "plate" style cooler to a dedicated Setrab unit.

What is hard for people to understand is the cooling system cools the outer shell of the engine, but cooling the critical internals is handled by the oil. The cooling system doesn't do much to help average oil temps. There is a good bit of empirical info on ideal oil temps. Add the fact that our clutches are the same design and materials as an automatic trans...... we need to gather that info as well. What we end up with is a very specific temperature range to stay in. There are many oils that will tell you that they are stable over 300°, but they don't tell you that oil breakdown and component operating temps are two separate issues that affect longevity.

The first thing we wanna do is get the oil up to 150° before leaning on the motor too hard...... maximum component and oil life will be between 180-210°, now we consider the auto trans style clutches start to show excessive wear above 190°. Keep in mind that temps lower than 180° don't do a good job of evaporating moisture that is a by-product of combustion that contains acids. So engine life can go down below those temps. That gives us a narrow "ideal" operating range.

Trans life


Engine life


Now here is something really interesting..... Notice that 5w-20 has higher viscosity at 180° than 15w-50 has at 270°. Why wouldn't I run 15w-50 and say screw it? Without the cooler you will see these peak temps, but then the thick oil throws the double whammy on you because it takes longer to transfer heat than thin oil, and when temperatures aren't up to peak, the heavier oil has far more parasitic drag. Now let's add the fact that oil's enemy as far as viscosity breakdown and overall protection value is heat. You could probably run thinner oil all season with controlled temps, and have better protection than you would with changing oil every race that gets outside the ideal range. You can see where an oil cooler quickly becomes better than the sum of it's parts.


Everyone probably already knows that I am obsessive about engine longevity.  It costs us almost as much to build our engines as it does for a V-8..... we should have the same reliability. That is why I had torque plates built.

Here are some more products that I think are worth looking into.....I think these are a MUST HAVE for XC, circle track and turbo guys. It's an awesome addition for trail/duner builds........Probably not the best money spent for guys that are strictly drag racers

Raptor 700 Oil tank - $129.95 : Joker's Vault, Custom ATVs and Accessories

BIG oil tank


Super durable cooler


5.6" fan for cooler


Of course there are many cool accessories as well, like thermostats and braided lines to make a simply awesome looking install. Once the oil temps are under control, the oil lasts WAY longer between changes...... So if you do this right, you can have better engine life and a way cool looking setup that pays for itself by not changing $10 qt oil as often. The biggest thing is you get to keep this nifty looking hardware instead of just throwing your money out with your oil. The first time you don't have to rebuild or have a catastrophic failure will certainly pay for it. Extended clutch life is a nice bonus too 

[Peelz]

Do you ever sleep? Or is it quad engines 24/7? One helluva writeup.

[Kenny]

Do you ever sleep? Or is it quad engines 24/7? One helluva writeup.

What is this sleep you speak of?

[Kamakazi]

why cant you sell suspension kenny?  i need to invest money into my suspension before i invest money into the engine again 

[Colorado700R]

Your stirring my coolaid kenny, and I like it


The stock Raptors Thermal Efficency is approximately .30-.32 @ sealevel, .28-29 @ 5,000ft ASL. Increasing the TE to .34 based on Carnot Efficency (1.00= perfect) can increase HP 30%.

If you require a major headache, read up, all this is tied to the second law of Thermodynamics.

This would be a pretty handy piece of Software to have for a designer/builder http://www.auto-ware.com/software/eap/eap.htm

[Kenny]

why cant you sell suspension kenny?  i need to invest money into my suspension before i invest money into the engine again  

That is kinda strange since motorsport chassis engineering and fabrication were my main study courses in college. I spent a good deal of time as a shock specialist building, dyno testing and maintaining AFCO,Bilstein, Ohlins and Penske for circle track and road course cars. I loved doing digressive valving......you would think this is a natural extension. It is really hard to find someone that understands that the spring controls the vehicle and the shock controls the spring. I am definitely better at chassis work than I am with engines  

Your stirring my coolaid kenny, and I like it


The stock Raptors Thermal Efficency is approximately .30-.32 @ sealevel, .28-29 @ 5,000ft ASL. Increasing the TE to .34 based on Carnot Efficency (1.00= perfect) can increase HP 30%.

If you require a major headache, read up, all this is tied to the second law of Thermodynamics.

This would be a pretty handy piece of Software to have for a designer/builder http://www.auto-ware.com/software/eap/eap.htm

Thermodynamics is a very cool subject to be sure, but it is easy to find yourself lost. Smokey did a lot with adiabatic engine design, but could not make it work on a broad scale. The main thing holding us back are the thermal barriers we have at our disposal.
http://en.wikipedia.org/wiki/Adiabatic_process
http://schou.dk/hvce/
http://www3.interscience.wiley.com/cgi-bin/summary/117937348/SUMMARY?CRETRY=1&SRETRY=0

[Krandall]

http://schou.dk/hvce/

If this motor is the saving grace to this world. why haven't we heard more about it? Seems like snake oil. or a good old fashion tornado intake

[Kenny]

http://schou.dk/hvce/

If this motor is the saving grace to this world. why haven't we heard more about it? Seems like snake oil. or a good old fashion tornado intake

Smokey had this dude working in a satisfactory way for a hotrodder...... Too much maintenance for the average Joe. Again, the current breed of thermal barriers just couldn't get the job done. With the advances in "nano" technology, someone concentrating on this design could probably make a gas powered engine as energy efficient as an electric motor without the weight and obvious environmental problems that batteries are gonna cause. You can see that one coming a mile away

[Krandall]

Gotcha,

I just don't know what the holdup is.. Seems in todays age, if there was an engine that was the "Saving Grace" of the motor/mileage world, we'd know and also hear more about it. I'm a firm believer in the oil company conspiracy theories. They have so much money I'm sure they have their hands tied all over keeping certain "projects" under wrap so their beloved oil keeps selling.

[Kenny]

 I think human nature has more to do with it than anything. People tend to do nothing unless forced to do so, and this is a case of "out of sight,out of mind". This car was coming to fruition when gas was $1.25 a gallon. Nobody cared. Hotrod guys think it's OK to get 60MPG if it happens on their way to the horsepower promised land, and environmentalists will not drive a 300hp car that gets 60MPG, unless you first kill 280 of those hp. You could easily reduce the cost of the system through mass production, but who wants to be the car company that has to convince the public that this is a good thing? I would estimate the cost difference to be $2,000 or so on each vehicle in mass production and $10,000 for a one off. We are only seeing about 30% of the total energy an engine makes because of thermal losses, so the science is legit. As we get coatings that are truly effective, you will see this filter into OEM applications as increased fuel efficiency and emission standards become more strict

[preddy08]

Kenny, whats your thoughts in engine ice, water wetter and alike?

[Colorado700R]

Kenny, whats your thoughts in engine ice, water wetter and alike?

Oh no you didn't.............

<Kenny cracking Knuckles, snapping neck, and jamming one letter at a time on the keyboard like a madman>

Enter.....The Vapor zone

[preddy08]

Kenny, whats your thoughts in engine ice, water wetter and alike?

Oh no you didn't.............

<Kenny cracking Knuckles, snapping neck, and jamming one letter at a time on the keyboard like a madman>

Enter.....The Vapor zone

I dont much care for that crap, but others seem to like it.

[Kenny]

  It works by reducing the surface tension of water. If you take a glass and fill it with water, you will notice that you can actually overfill the glass a little.....making a water dome of sorts. That is the molecular chain in the water that holds it there. If you put a drop of dishwashing soap in it, the molecular chain breaks down and the excess water will drain right off. You will find many localized areas of boiling water in an operating engine. Of course every area that has this going on is dry. when you break down the molecular chain, it allows these areas to be more thoroughly "wetted". It does have some effect and it usually has a good water pump lubricant that is an improvement over distilled water alone. I can't imagine that it does anywhere near what they advertise....... and you damn sure can't cool 195° water to 175° if you have a 195° thermostat. It can help transient temps though. I run it (the cheapo wal-mart version)....... I personally believe that anything that helps bring things to an "average", instead of wild swings is a good thing no matter how insignificant. Little things with seemingly little significance may have a cumulative effect and become significant.

To put that in hillbilly perspective: If you sling enough shit, some of it is bound to stick

[Alkire193]

Got mine, looks great!



You dont have to modify the mounting brackets for the radiator to install this!