Ahhh, there's that chemistry.

 

Got any pics of what your shroud looks like?
I tried one and it ran hotter on the highway. Took it off and it's back to normal.

 

This fan is quite special, imho, it is a brushless digitally controlled constant speed fan 16" 2800CFM fan. No matter the voltage or airflow, the fan speed will not change. It also draws considerably less current than any fan of equal CFM, especially when on the freeway,... if there is enough flow through the radiator to turn the blades, the current drop is significant, and its EMI output is considerably less then brushed fans. This is important for systems like mine that have EFI and are susceptible to EMI.
Its also considerably quieter than the old Spall fan that I had. And less than half the weight!!

http://www.deltapag.com/Technology.html


http://www.deltapag.com/uploads/Delt...n_Brochure.pdf

 

Yes...you are correct. BUT...the 'heat' being discussed in this post is the 'heat' that we want to get rid of and control it to a point where the engine will perform correctly and stay 'balanced' within an operating temperature. Which...if the coolant temperature is left unattended/controlled...can cause an engine to 'melt down' if it gets hot enough. And...'melt down' is not literally meaning that it turns into a pile of molten metal...but ...those who have had this happen to them ...know what I mean by it. Either way...it is NOT a good thing.

Case in point: ( When I watched a show on TV about it being built) The Bugatti Veyron...when being dyno tested to achieve the 1000+hp. It actually produced 3000hp....and 2000 hp were lost due to heat in the exhaust.....which was SO HOT...that it set the roof stacks of the dyno building on fire. It has NUMEROUS radiators to control this heat issue.

DUB

 

The heat is a by product. In our standard Corvettes, it is wasted energy.

 

I respectfully have to disagree. By far, the single greatest issue with electric fans is improper ducting of air (and controlling it) through the entire surface of the radiator. I roll my eyes when I see a car with a round caged fan held to the radiator with through the radiator zip ties. No wonder these cars overheat. A properly shrouded electric fan works fine, provided the wiring is in order. I'm running a dual Ford Probe fan setup cooling a 550 hp LS3 in an old C3. The computer's PCM controls both of them. Never overheated once, and it's cooling a much larger engine than it was designed for. All about DIRECTED air.

 

was curious on that so I did some research. there is very little difference assuming they are made with same materials and same surface area. the difference is that the cap is on the low pressure side on a side flow vs. the cap being on the high pressure side (on top by design) of a top flow. the cap will vent sooner and overflow on a top-down radiator as a result, whereas a sideflow can be sealed.

 

That may very well be true...but what are you going to do.

So many scenarios in life cause for 'things' to be wasted. Peeling apples to make and apple pie..I am not going to worry about the peelings. And worrying about lost heat energy of a normally aspirated internal combustion engine that is driven on the street. I really do not give it much thought. One of the few thoughts that I do pay attention to get trying to get the exhaust system to get the heat out and not suffocate it.

Obviously...to each his/her own....but... I have learned to not get 'caught up' in the numbers....and the 'what if's' When engines are being dyno tested and tuned. Trying to get every last bit of power out of the engine....which I am all for that. And the owners are on a mission to achieve 'numbers' that will make them happy. I have come to find that a vast majority of these owners never utilize the potential of the engine that they are building to these 'numbers' once completed. Which is their choice and is fine by me. People can spend their money on what makes them happy....but I try to get them the best 'bang for their buck'.

And like I try to tell them that on the street...20 hp and 30 lbs/ft of torque gain is something that you really can not feel.....depending WHERE this improvement is in the curve....and what the initial hp and torque was before it gained by the example above of hp and torque.

DUB

 

Good stuff Dub.
I guess I just wanted to point out what the heat is in this example. Physics teaches us that in an energy conversion, you will always end up with less usable energy than you started with. Generally the wasted energy is given off as heat. The higher the energy efficiency, the more useful work we are getting for the same amount of energy being put in. There is no such thing as a 100% efficient energy transformation.
That's what I was talking about. It's all good and I can tell you know a lot...

 

Saw something odd this weekend at a Pontiac car show. None of the '66/'67 Catalina's and Bonnevilles had any fan shroud at all, just a little guard at the top with a warning sticker. They all were automatics, had clutch fans, but no A/C

 

a lot of old cars didn't have fan shrouds, especially 50's/60's. radiators were a lot bigger, there was a lot more room under the hood, grills were larger and unobstructed, plenty of airflow, air conditioning was rare...the list goes on.

my '73 spitfire did not have a shroud, instead, there were 2 pieces of cardboard bolted to eac side of the radiator to act as an air duct. yes, I said cardboard...gotta love the brits'...

 

They were V8 cars, and the radiators actually looked pretty small, and the Pontiac nose blocks the center of the radiator. Just saying......

 

That reminded me.... my 72 AMC Jeep CJ5 304 V8 ...had no fan shroud at all.... never had a problem....I believe the 304 was rated around 150hp, and 245tq

Well, That was until we put in a full roller AMC 360 450hp 475tq to take its place....
now we seem to need a fan shroud:-)

 

That is one of the first things I learned, when I first started crewing on road race cars in the early 80's.

I was taught to think of air like water. Just like water, air will take the path of least resistance. If you want air to go through a radiator, oil cooler, trans cooler or rear end cooler, you have to make the air go through it. To make a radiator cool effectively without a fan, you have to force the air through it, and the same is true, if you want a fan to draw air through a radiator effectively. A properly designed and sealed shroud is needed for any fan, electric or engine mounted, to operate effectively.

What people tend to overlook, is that Corvettes have a very small grill opening, especially when the headlights are closed. Corvette radiators get most of their air from under the front bumper. Before playing with electric fans and other fixes, the first thing people need to do is check to see if the front spoiler is there and in good condition, along with the valance panel and all of the radiator seals.

 

I understood where you were going with your comments and trying to communicate. I knew what you meant and were saying about heat in the issue of lost power. And I am glad to read in your reply comment that you are not one of those people who are hell bent on having an epiphany.... and figuring out how to 're-invent the wheel' and find a way to ACTUALLY get 100% efficient energy transformation.

AND... if you do.....heck...let me know. Because I can keep a secret......because if it got out that you did.....you would be....uhhhhh......ummmm......'probably' be getting the attention of many people who would not want this to come out.....if you get what I am trying to 'say'.

DUB

 

Bingo ......nailed it