[killerbee]

Overheating season (for all HD trucks) is upon us again, and there has been some interesting developments over the winter. MIRACLES have evolved.

Including one unnamed who says, just getting rid of the fan allows him to run a grade at twice the speed he used to be able to. Yup, you heard it, doubled his HP by just eliminating a parasitic drag. And he has no explanation for it, except going to electric fans must have somehow been responsible for this.

Please, please, I am getting emails about this now, and I would like everyone to please use common sense.

Electric fans, for all the complexity it creates, has one, and really only one main advantage. Helps keep hot air out of the intake. You can do this by adding a good CAI, and simply increasing the size of the fan pulley on the stock truck.

The smaller LLY fan pulley is a tragic production mistake. The fan drive ratio was increased out of optimum, by an engineer who needs to go back to school. The highest fan speed when engaged, is a realized reduction of airflow, and increase in parasitic drag, compared to the LB7 pulley. Replacing it will net fuel economy benefits in all regimes, and is one of the main reasons for observed mpg decreases in LLY vehicles.

The fan is suppose to be an axial device, pulling air through in a straight line. the increased speed of the LLY fan makes it perform more like a centrifugal device, shrouded by an axial shroud design. The net effect of this is heaps more turbulence, and centrifugal overflow of this high pressure heated air, right into the low pressure intake. The result of preheated intake air is left for separate discussion, but it is key to the D-max heat issues.

This was all concluded about 2 years ago. A side note: even claimed Cold Air Intakes, are somewhat victimized by this fan. This was a tough lesson to learn.

 

[TxChristopher]

This is gonna be fun. opcorn:

 

[Guest]

Lets keep personal flames and name calling out of this thread. Either bring pertanent information, backed up by facts...to the table...or back away.

 

[TxChristopher]

Before anyone could possibly argue a point they would need another basic but key component: history of the subject at hand

The truck in question pulls the exact same route every year at the same time to be at a yearly convention. The owner is very familiar with the truck in question, it is his third Duramax truck no less. Three times as many Duramax trucks as Killerbee has owned, he is on his first.

With this SAME EXACT TRUCK in question, in stock condition, the owner would experience overheating and continuous fan up the entire extended grade. Floored the best the truck could do was hold 25 mph as long as the grade persisted. Even in 50 degree weather this was the case.

A known baseline existed. So the question was, how to change this?

 

[TxChristopher]

Lets keep personal flames and name calling out of this thread. Either bring pertanent information, backed up by facts...to the table...or back away.

I got it, its cool, thank you for keeping this on track. I have a whole lot more coming. This "myth" is not a myth at all but rather a well thought out and planned accomplishment that is wrongly being dissed by an uninformed commentator. :Thumbup:

 

[killerbee]

Yes, start with the basics.

Power required=acceleration + drag(wheel and wind) + elevation change

We tow trailers at nearly constant speeds, so this reduces to:

Power=drag+elev change

Wind Drag is mainly going to be dependent on Cd and vehicle speed, increasing with the square of the speed IIRC. Wheel drag is around 10-15% of this and relatively insignificant.

For the second half, elevation change, all that matters is weight and rate of climb. Going from 30 to 60 on the same grade, represents twice the required power to do so, as you cover twice the altitude in the same unit of time. There is "no free lunch".

To double speed on a grade you would need more than double the available HP because of the square relationship of wind drag. Example There is 36% more drag at 70 mph than at 60, and the force needed for that added 10 mph represents the same power needed to go 35 mph. doubling speed fropm 30 to 60, represents a 400% increase in power required to overcome that added drag.

So eliminating a fan does squat for forward speed and HP, unless claiming it sucks down over 200 HP to drive it.

I honestly don't have time to play games with you, AGAIN. If claiming 100% speed improvements on grades, by merely removing 20 HP of parasitic fan drag, on a 270 HP vehicle, maybe I am confused.

We benefit today from REAL pioneers, like Newton who helped us understand the gravitational constant, and trying to rewrite the proofs of pioneers is always a hard sell. Amusing to watch regardless.

I love my fan! Now that the TD-EOC has silenced it. But for some reason, I can't tow at twice the old speed! I have had bad diesel batches, I have had restricted fuel filters, I have had 200 degree intake air, and conquering each one helped me double my speed. Maybe I need an electric fan, maybe it is like the blades of one of those everglade boats.

Maybe your friends brakes were dragging. That seems epidemic out there. I don't know, and I don't hardly care.

 

[TxChristopher]

Put your vendor status here on the line if you are so confident what WAS done CANNOT be done. You don't even come close to knowing about what was done or how it was done, that is very obvious.

So, don't talk in circles, don't talk in parables, leave out Newton because he has no info on what was done either....... talk facts like the man said. Or back down.

I like the part about you putting your vendor status here on the line. Are you confident and man enough for that??????

 

[TxChristopher]

Put up or SHUT UP. I prefer PUT UP you take SHUT UP

First I apologize for anything taken wrongly about anything I said.

Look guys, its never my goal to cause your board trouble. You have a really nice place here, and a great policy for keeping members protected from bashing. I like and respect that.

However, you have chosen to allow Killerbee to be a vendor, and as such his opinions will tend to carry more weight than the average member. As a vendor he is supposed to know and even assumed to know what he is talking about. With that understanding he cannot be allowed to fire off on other peoples products without some real proof to back it up. Its just not professional to do so and reflects poorly on your site. I am not a vendor here, but STILL it is unprofessional to bash someone elses stuff arbitrarily.

As for the truck that doubled its speed with the same load..... did it have double the power? More than double? Maybe so.

Here is why:

1) Pull was made at 1800 rpm which is where 55mph lands at, truck makes 605 lb/ft of torque at this rpm and since hp = torque x rpm / 5252 so we are only talking 207 horses to start with. Thats flywheel rated, industry standard is 85% to the wheels so we are at 176 to the rear wheels.

2) We have measured the amount of power full lockup fan takes, it is roughly 40hp at the wheels and as much as 65lb/ft of torque. Thats 22% of the pie right from the get go, as was stated the truck previously had full lockup fan during the climbs. 176/2 is 88 horses, we lost 40 of them right off the bat.

3) The key term is that the truck was OVERHEATED on every previous attempt. This truck has not only an electric fan kit on the main rad, it also has a V2 with fan below. So it was no longer overheating. I have EFI Live and can tell you that with the truck overheating the ECM defeuls like crazy to try protect itself. From tables in EFI Live: "Once the engine coolant temperature reaches 244°F / 118°C then the ECM will start to reduce the amount of fuel injected in an attempt to reduce power.
The values in this table show the amount to reduce the final injection fuel quantity by, not the final fuel quantity figure, the values in this table are then further adjusted by {B0746} "Engine Overheat Fuel Quantity Multiplier".

Key term here is it will "reduce the amount of fuel injected in an attempt to reduce power"

Its fairly common knowledge that every engine already makes less power when it is hot, this one deliberately reduces power. We are only 48 horses away from being at half the power, or 28% if we stick to the math. Reasonable to believe it lost 8% to running hot and another 20% to defueling itself?


4) None of the above matters or even CAN be argued, or needs to be calculated or argued because we do know one thing for sure: The truck topped out at 25 mph previously and hit 55 mph easily on the last pass. Doesn't matter any of the rest, thats it, those are the results

Hopefully this issue is settled and we can all still be friends and move on to better things. :Thumbup:

 

[TxChristopher]

From myth back to reality

Any other questions? opcorn:

 

[mckey73]

Any other questions? opcorn:

Why does my head hurt?

 

[fingers]

2) We have measured the amount of power full lockup fan takes, it is roughly 40hp at the wheels and as much as 65lb/ft of torque. Thats 22% of the pie right from the get go, as was stated the truck previously had full lockup fan during the climbs. 176/2 is 88 horses, we lost 40 of them right off the bat.

That is an interesting statement. The attached pic is of a 10 HP electric.

Regardless, an interesting thought. So this truck overheated even with the V2?

 

[TxChristopher]

That is an interesting statement. The attached pic is of a 10 HP electric.

Regardless, an interesting thought. So this truck overheated even with the V2?

No, it overheated before the V2. Now it doesn't anymore. First we put on the V2 with fan and eliminated the overheating, then replaced the stock engine fan with electrics too.

The fan is chewing up tons of power Fingers, we spent a week planning on it and then a whole day doing tests to see how much power it eats. It is substantial. There are extensive test results on my forum. The lockup fan cost the truck over a second in the quarter mile and over 2 mph towing a moderate load versus the Fan Damn electrics.

Its kinda obvious the fan eats way more than any 10 horses, as any owner knows acceleration of a stock truck towing much of anything up a grade is over with if the fan engages full blast. The truck literally falls on its face.

 

[TxChristopher]

Why does my head hurt?

Have you seen it? LOL

 

[TxChristopher]

That is an interesting statement.....

Also, it took a 65 horse tune added to a comparison truck that we also repeatedly tested the same day for it to equal the acceleration of the otherwise stock truck with only the Fan Damn electrics.

 

[mckey73]

Have you seen it? LOL

nice :Thumbup:

 

[TxChristopher]

nice :Thumbup:

Its the same thing I tell wifey when she says her head hurts. :damnit

"Well look at it. If I had a head like that I am sure it would hurt too!" LOL


She doesn't seem to be as amused as I am about it even after the 2,493rd time

 

[TxChristopher]

Lets be clear everyone, horsepower is highly dependent on RPM, it has to be because its a straight function of it. The FAN in the picture Fingers posted is not a 10 horse FAN. The MOTOR in Fingers picture is rated at 10 horsepower yes, but that is if it is allowed to turn at a certain RPM. That motor only has so much torque, and if the resistance is enough to slow the motor down it will no longer be a 10 horsepower motor. It can only power that huge fan because there is massive gear reduction involved, there is a very small pulley on the motor and a giant pulley on the fan blade.

So that picture is not an example of "a 10 hp fan", do not be misled by that or confused into thinking our engine fan cannot eat more power than that big fan. Take away the pulleys and hook that motor directly to the fan and it likely will not be able to get the fan going, and if it did the motor would be pulling huge amperage and would not last long as it overheated. If you were to run the fan directly off the motor shaft you would have to shrink the fan way way WAY down. Everyone on the same page?

Its the high torque that generates any reasonable horsepower at lower RPM.

 

[swatkins]

Overheating season (for all HD trucks) is upon us again, and there has been some interesting developments over the winter. MIRACLES have evolved.

Including one unnamed who says, just getting rid of the fan allows him to run a grade at twice the speed he used to be able to. Yup, you heard it, doubled his HP by just eliminating a parasitic drag. And he has no explanation for it, except going to electric fans must have somehow been responsible for this.

Hi folks...

I happen to be the "one unnamed" mentioned above... After reading the whole statement he posted I must say it is full of inaccuracies and if you would like to ask any questions and get the information "from the horses mouth" I am here and ready to answer your questions first hand.

Here are some of the reports I posted to give you an idea of what really went on

This is a repeat of the trip I took to San Diego last January...Same truck, same trailer same route and same time of year...

This time I have added 60 gallons of diesel and about 300 lbs of generator to the load... I will be weighing in at 21,000 lbs and hauling butt.

This time the factory fan is sitting in the closet of the 5er!!!!! I expect to not hear a peep out of it and I hope it enjoys the ride up the hill!

So far, so good!


Made it to Van Horn Texas today... That's 648 miles, with no stupid fan noise and 8.9 MPG! I can make it into El Paso without having to fuel!!!

Did I mention I was doing at least 70 all the way?

I also went through the same route Tx is showing in his overheating video, pulling a higher load and about the same weight... I was doing 70, with the AC on, and talking to my wife in the back seat without having to shout! It was only 72 outside but the speed was making up for it

The V2 fan came on for about 2 minutes, only at the top of some really long climbs. When it came on both rad fans shut off really quick and only started back up , they are set to run at 190 degrees, when the v2 fan went off

I checked in on the factory fan every 2 hours just to make sure it had not committed suicide. I was afraid it would be so depressed from being made the second string (and soon to be cut all together!) fan, that I placed it on suicide watch.


Tomorrow gets me closer to that BIG HILL!
So far, so good!

Ok,, I'm plugged in!

It's really nice to see so many parks serving free wifi that will reach inside the RV.. Makes life on the road a lot easier when you depend on the Inet so much. In fact if the trend keeps up I may have to rethink wanting one of the Data Storm Links on top of my RV.............................. NAW

Tonight I am 20 miles south of Phoenix sitting in at a park inside the Y made where I-10 and I-8 split.... Too bad I don't know where KB lives or I could drive by and show him what a real cooling system looks like

Today I started the run at Van Horn and drove the 505 miles to this location.... Once inside New Mexico the speed limit went up to 75 and so did I Guys I know this sounds stupid and I am not sure why it is but when I go faster than 70 this truck gets better mpg's! Today I was going 70 for 120 miles and then 75 the rest of the way. Same wind conditions as yesterday, hardly any, and I used 53 gallons to go 505 miles... 9.5 MPG ! That's even better than yesterday..... Hauling ***. BIG tall trailer, over 21,000 lbs and riding in style What a life !

On to the report....

Started the day off in about 50 degree temps... Got warmer as we went until I saw 82 near Benson AZ... Now for the good part... For the first time on this trip I saw the factory gauge move It was on a long 4 mile climb , maybe a 4/5/6 % combination climb with the outside temps at 82... The factory gauge went to 210 while the top rad hose gauge climbed to 220 by the top of the hill.... Of course this was while I was still cruising along at 75 MPH passing all the other poor slobs and people pulling 5ers up this hill with this surprised look on their face as we waved to them

Once I topped the hill the temps dove back down and the fans started shutting off...


Tomorrow I have a date with a hill... Maybe it will be hotter, I hope so... Last year it was in the 50's when it brought me to my knees.. To count it as a success I want to be able to power up the hill... 25 MPH was the best I could do last year. Make no mistake it's mean hill and I might not be able to go over 50 without getting it too warm, but 50 is one hell of an improvement and I will still be able to listen to the radio on the way up

The one thing I am impressed with is the ability for this setup to recover... From all of our summer testing we know it can't stop a temp rise if it's a balls to the wall screaming climb. I hope to prove it's more than able to do a respectable job on a regular controlled climb.

Today I arrived at the HILL...

Outside temp was 72,, about 20 degrees higher than last year when I could only go 25 MPH up the Hill.. This sign greeted me at the bottom of the hill.....

The climb starts out below sea level and ends up at 4150 feet after about 8 miles... There were no grade signs posted on the up hill side but the down hill side had warnings of 6% and the climb up had some that were much steeper that the down hill side.

On the way up I saw one pickup with a small trailer pulled over at one of the emergency water stops the state placed every 1/4 mile on the hardest parts of the climb.... Steam was pouring out of the hood area so I guess that he forgot to turn off his AC.....

Then Disaster hit!

When I was getting ready for the trip I was checking all the wires and forgot to tie one back up

Halfway up the hill I lost the right side rad fan and the temps shot up to a coolant hot warning! I pulled over and waited for about 2 minutes for the traffic to clear and I watched the temps... Within 2 minutes the two remaining fans brought the ECT temp back to normal levels! I figured out that the wire I forgot to tie up had rubbed on one of the pulleys and shorted out! I taped it and replaced the fuse, Got back into the cab and kicked that hill's ***!

I started from a dead stop on a 6% grade.... Pulled into the main lanes and by the time I topped the mountain was back up to 55 MPH !

All of this in weather that was 20 degrees warmer and pulling at least a 1000 pounds more than last year!


Oh, I must have forgot to turn off the AC at the bottom of the hill :evil:

Quote:
Originally Posted by TxChristopher
So it sounds like the old 25 mph record on "the HILL" was beaten soundly? Was the ECT manageable up to the point of the swatkins induced REAL LIFE TEST?

.

My reply
Yes they were,,,, Keep in mind it was only 71 or 72 outside so I left the AC on and was not trying to really baby it up that hill...

I had POWER!!! Last year was a totally different trip! No power, Fan roaring so loud I could not hear anything and 25 mph up the hill... Once I got behind a truck that was going even slower and once I slowed down to his speed I could not go any faster when the opportunity to do so came about.

This year I could have gone even faster it I wanted to


What this setup will do in the heat, on this hill, is really unknown... I wish it was hotter but It is what it is... With all the driving and testing so far I can say I would have not worry if I had to tackle this hill in 95 degree heat. If worse came to worse I could pull over, or reduce the fuel input for a few minutes and then continue after the fans did their job

Well that just some of the report, I though it might help clear this matter up.. If you have any questions I will be happy to answer them and give you any information I have

 

[swatkins]

Here is my rig

Here is a picture of the rig....

It's not a baby trailer

 

[swatkins]

A few pictures of my rig

Here is a picture of what I use to measure the temps of my engine..

This is a very nice Trippin mount that I modified a bit

It has an auto meter water temp gauge on the left. This gauge is not tied into the trucks system and uses it's own sensor mounted inside the coolant stream at the inlet to the main radiator... It has been checked with digital measuring equipment and is accurate.

The Gauge on the right is an auto meter oil temp gauge and it is also not tied into the factory system. It's sensor is mounted in the oil filter housing BEFORE the oil goes into the factory oil cooler...

This Gauge is the BIGEST WASTE OF MY MONEY on the truck! I bought it to once and for all check the oil temps and see if I needed to add an oil cooler... I do NOT need an oil cooler... The fact is the factory oil cooler is more than adequate at keeping the oil nice and cool... I never see the oil over 40 degrees above the engine coolant temp. Most of the time it is 20 degrees above engine coolant temps as measured by the stand alone gauge mounted beside it.. The factory oil cooler is able to keep the oil temps very well under control.


This is a picture of the prototype fan system on my truck..

It is a little different that the production model... First it is using a different shroud... I made this one in an effort to improve the performance,, Turns out it did no better than the production shroud.

I had a 1956 chevy that was running hot,, 350 engine, small rad... so I built this one for it It is using 14 inch Spal fans
where as the one on my truck used the long life 16" Spal fans..

The only other difference in the prototype and the production model is the electronic control system.. The prototype is using two electronic controls instead of the production systems one.. This was done for testing purposes and gave greater control over the system for testing.. The one I made for the 56 chevy uses the standard Spaul controls that are on the Fan Damn system.

The three green light on the right of the gauge mount are indicator lights for the fans... There are three fans... On is on the V2 mod and one each for each of the fans on the main radiator... When the fans come on I see the LEDs light up..

The two SPAL main fans have been running 100% of the time since installed last summer. Sort of a long endurance test if you will... The V2 fan never runs unless I am towing and so far has ran very little even then..

I am seeing a very nice increase in MPG. MPG before the fans was 15.2 to 15.4 with a mix of city and freeway driving while not towing.. {I drive 70 or a little faster on the freeways ) ... That increased to 16.8 ( and sometimes better) after the fans were installed..



More later,, My fingers are tired