Fast or Slow Coolant Flow
Hello! I work with my dad's racing team on the engine side, researching/suggesting components and specifications to ensure the engine holds up, cools well, and makes good power. As such, I enjoy reading Circle Track, it gives me some good insight on the parts, technology, and theory as it applies to cars specifically designed for this type of racing.

But, your Nov. '12 issue has a very glaring error, I hope it's corrected for December. Jim Mcfarland wrote "Cooling for parts life and power." Unfortunately, he included the misguided theory that you can move fluid too fast through the radiator. While I may be nobody in anyone else's eyes, I know this is incorrect. It flies in the face of the realities of the cooling system.

In any case, instead of me arguing it, and explaining the physics, I will point out for your review, that on this very website exactly one year ago, Jeff Huneycutt got it right. I would suggest you have Jim read that article. He might even want to talk with the folks over at Stewart Components to get an even better understanding of why there is no such thing as moving coolant too fast (obviously, as long as the pump isn't cavitating).

I'd appreciate it. This myth has gone on for far too long, and too many people still believe it.
-Dorian Yeager

We certainly are investigating this and I will give you a little history of where it came from. And by the way, I took thermodynamics in school some time ago, so I have somewhat of an understanding of heat exchange.

Years ago, Smokey began experimenting with improving cooling in his race engines. Remember that radiators were not as well developed in those days as they are now. He would restrict the flow of coolant and lo and behold, the coolant temperature went down.

I can tell you that in my Jeep, when I get in it on a hot day, if I put the temperature on high and the fan on high, the output is warmer than if I slow the fan speed down. That means that more heat is being removed from the air passing through the cooling radiator of the air conditioner when the air is moving slower.

It's no different in a radiator in your race car. It is true that there might be an optimum speed for the coolant to travel and if you run it through too slowly, the coolant in the engine might gain more heat and be harder to cool. But on the other hand, if you run it too quickly than optimum, it won't have the time to exchange that heat to the outside air before it re-enters the engine block and begins the re-heating cycle again.

What I am saying is that the question is a good one and the answer may not be cut and dried. We need more information and it may be as simple as, our radiators are now so efficient that we can move the coolant more quickly through the radiator than ever before. But I can tell you unequivocally, that at some point in the past, this was not a myth and it definitely worked.

Concussion Response
I just got done reading your article on Jeff ("One Hit Too Many," Oct. '12). Thanks to both of you. That's very good information. I'm an SCCA road racer and suffered a traumatic brain injury (TBI) in 2008 and have been able to get back to racing.

We don't crash as often in road racing but we still crash. I know this, but continue to race. I now have a full containment seat, HANS, changed the design of my rollcage, quality belts, and more.

I started a website that deals with TBI, I use my racing to give hope to others with TBI. Racing is my life as well. My TBI changed my entire life. I ended up divorced (my choice) but have been lucky enough to continue my job.

I would like to hear your and Jeff's comments about my situation and website.

Thank you,
-John Mills

Thanks for writing. Yours is not the only letter I received on this subject and it is the focus of my comments in this section this month.

I think we are all different in our physical makeup and some will be able to deal with concussion better than others. We must evaluate our own situation and make decisions that are right for us. We are not trying to say that everyone will progress into what Jeff has experienced. What we are saying is that it is a possibility and if we can educate drivers to the exact symptoms and progression of those symptoms that may lead to cronic post concussion syndrome, then we will have accomplished our goals.