Air Intake Temperatures

[Archive]

On Rob's old website there was a discussion about the effects of air intake temperatures a few months ago.
Four Wheeler magazine had an interesting article on page 62 of their August issue. Although it's about improving mileage on a gas powered Ford, I think their data can be useful to us Cummins owners.
http://www.performanceunlimited.com/projectmpg/airtemp.html shows a chart comparing a stock and K&N air filter and the resulting tempurature drop when insulating the air cleaner and ducts. You can find more information by browsing around this website. The insulating tape they used on the air cleaner and intake ducts was made by http://designengineering.com . The Four Wheeler article (part of a series called "Project MPG") made for some interesting reading. I could quote the results of their tests, but it would make for a very long posting.
What I'm wondering is: will insulating the air cleaner and intake ducts make any difference on our trucks, or does the intercooler work so efficiently that it wouldn't make a difference?
Comments?
Andy


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'97 CC 4X4 5-speed, too much to list here, on cover & pg. 91 of TDR issue 24.
Be sure to visit Northwest Custom


[This message has been edited by Andy Perreault (edited 08-27-1999). ]

 

[Archive]

I think the only part of the intake you would want to insulate would be pre-turbo.
My reasoning is as follows:

Air going to the turbo is at ambient temperature plus any heat it has absorbed while being in the engine compartment/air cleaner, and air hose to turbo.

Compressed air leaving the turbo has been heated (by compression and the heat of the turbo itself) to over 200 degrees. It then travels to the intercooler where it is cooled to around 145 degrees then to the intake manifold.

So as I see it, once the air leaves the turbo it is actually hotter than the surrounding air of the engine compartment, so heat absorption by the engine compartment should be encouraged, and insulating the hoses after the turbo would actually keep the air hot vs. helping it cool off.

Of course, this assumes the the engine compartment temperature is cooler than the temperature of the air after it leaves the intercooler. If this is false, then I would prefer my crow be served well done with worcesteshire sauce.

-dm

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98. 5 24v 5-spd std cab dually
What Dale Earnhardt did to Terry Labonte was WRONG!

 

[Archive]

Good point, DM. You're absolutely right. I wasn't thinking about the temperature-raising effect of the turbo compressing the intake air. On the study I mentioned involving the Ford, the underhood temperature was 157 degrees when the ambient air temperature was 70. That's a whole lot less than the 200+ degree temp of the turbo-boosted air that you mentioned. Insulation would be counterproductive. One thing I was wondering about was would it help to insulate the tube that leads from the downstream side of the intercooler to the intake manifold. It's right in the path of hot air coming out of the radiator. I'd like to install a temperature gauge to measure the air temperature at the intake. It would be interesting to see if insulation would make a difference. Another one of those "one of these days" projects!
Thanks for your reply.
Andy

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'97 CC 4X4 5-Speed, on cover & page 91 of TDR issue 24.
Be sure to visit Northwest Custom

 

[Archive]

Andy, I'll try and find where I saw those numbers... I am positive that the temp out of the turbo was around 245 degrees, I just can't remember if the intercooler cooled the air down TO 150 degrees or cooled it DOWN 150 degrees. If the latter is true, and ambient underhood temp is 150-170, then insulating the post intercooler tube would help.

Unfortunately, I have more ideas than money..... Anybody out there want to sponsor a research project?????

-dm

 

[Archive]

Andy

I like to debate this same subject. I have been against using a hole saw to cut holes in the airbox since this would eliminate the increasing positive pressure as your vehicle speed increases. Also the additional air would show some heat gain from the rad. and intercooler, not to mention the engine.

Discussed this with one of my hp gurus a while back and he reveiled his testing data
showed little post intercooler change either way. In other words deviation in temp at the airbox didn't translate to commensurate temp. diffs. at the intercooler outlet.

He suggests swiss cheesing the box and take your performance gain from improved air supply imparticular prior to the turbo spooling up.

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98. 5,24v,3/4 ton,2wd,lsd,5sp
blue box hp enhancement

 

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Hvac, this situation sounds like a perfect thing to be tested with one of BMann's in-truck dyno's.
Andy

 

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I encourage the development of the dyno (Drag Racer?) mentioned. I would be a candidate. What do you suppose the parameters would be for accuracy. If I may answer my own question, I suppose that remains to be seen. I guess my point was that some (a lot) of this stuff is subtle in hp gains. KN verse OEM, for example. The large holes in the airbox is directed at low vehicle speed air supply, not peak power.

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98. 5,24v,3/4 ton,2wd,lsd,5sp
blue box hp enhancement

 

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Well, I was close, actually bmann was suggesting the dyno idea, not drag racer.
I just don't see how we can fit a chassis dyno inside the cab?

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98. 5,24v,3/4 ton,2wd,lsd,5sp
blue box hp enhancement

 

[Archive]

The "In Truck Dyno" will be very small. It's the LSI chips and programming that make it work.

Take a look at http://www.performanceunlimited.com/projectmpg/summary.html .

I will NEVER complain about fuel mileage (repeat 500 times)


Ben

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2000 BLACK 3500, CTD, 4x2, Quad, SLT+, Tow Package, Camper Package, Sports Package, Sure Grip, Sliding Rear Window, 3. 55, Auto