Use your A/C to cool your engine!
 

I was just daydreaming about ways to increase engine cooling in my 3.2, and I'm wondering about the potential effectiveness of using the A/C blower output in various ways, such as:

1. Redirect the blower output from the smuggler's box to the front oil cooler instead of the car's interior.

2. Relocate the AC evaporator/blower to the engine compartment where the heater blower normally is. Since you don't need heat in the summer, that stuff can come out anyway. Connect the blower output to the heater tube connected to the fan shroud. Not only would cold air be added to the fan’s airflow, but the blower draws hot air out of the engine compartment and circulates it through the evaporator.

3. Do #2 above, and also add Grady's Rubbermaid Solution by inserting a misting nozzle into the cold air stream as it enters the shroud area. And since your smuggler's box is now empty, use it to house the Rubbermaid water supply.

4. Instead of blowing the cold air on the engine, instead connect the blower output directly to the horn on the airbox cover, thereby feeding it cold intake air even on a hot day.

The A/C plumbing for the evaporator relocation would require a short 3' run from the compressor to the evaporator, and a longer run from the front condensor to the evaporator.

Any of these ideas have potential?

dave..tell the truth..your unemployed right now, man..;)
ryan

... in this house, we obey the laws of thermodynamics! ...

(no AC, but installing a fan on the oil cooler is workable)

(added thought - we keep calling our cars air-cooled, but are they not oil-cooled?)

Really think so huh, why don't you disconnect your air cooling fan for some more horse power, and your car will be faster! Let us know the results :rolleyes:

Can I disconnect my oil cooler then?

sure..the auxillary!:D
ryan

Re: Use your A/C to cool your engine!
 

am I correct to assume your engine is hotter than you'd like especially when zipping through the mountains ?

Describe a scenario.

...I think #3 has good bang for the buck.

But consider going with a nalgene-tank of say, 12 - 15 gallons...That would increase your capacity. It would eliminate the cords (bungee) especially if it was a factory look molded fabrication - fitting the 911 bonnet shape perfectly.

BTW, there are many more threads on this board 'inviting' more heat - not less. Hopping up a motor almost always produces more.

If you dissassemble the motor and drop the compression from 9.8 to
9.0 - you would achieve some benefit in cooling the motor. A few guys here would be unhappy at 8.5 or 8.0. UNLESS, they lost a MAJOR amount (3-400) pounds out of the car. Probably, you could live quite nicely running 8.0 to 1 compression at 1800 lbs.

What 911's really need is a kind of ultrahightech solar 'still' that could help replenish some of the supply of water for your mist. From what I know of stills, they tend to produce only a few ounces of water at a time.


Phil
_________

'74 fiat 128
'80 928
'82 Targa - sold

Guys,

Give Dave a break for “thinking outside the box.” This is where wonderful ideas come from.

I think all the engineers should calculate the HP benefit from cold intake air compared to the HP cost of running the A/C in reverse. My gut (thermodynamic) reaction knows the answer but I would like to see it on paper before dismissing Dave’s proposal.

Of course my two favorite (sucessful) solutions are the engine cooling fan ratio and the “Rubbermaid Solution.”

Best,
Grady

You can generate a refreshing breeze in a hot gymnasium by running some laps. ;)

dave..have a box 'o brakes on me..:)
ryan

http://forums.pelicanparts.com/uploa...1143237382.jpg

There's a real shortage of hot tea while I'm driving - how about using the oil-cooler's heat to boil some water that's accessible from the cabin, while simultaneously running my engine cooler?

Babak

Yeah, and increase the car's weight by 100-125 lbs!

ianc

a little over 2 hours and we STILL have failed to re-engineer the car's ability to dissipate heat to any appreciable degree! we must need more minutes..we'll get there..;)
ryan

I suspect driving technique is a possibility. I had to learn to adjust gearing during Rocky Mt rides. A CHT was a big heads up that registered way before oil temps. Once the oil was hotter than desired it was a pia to cool down.

umm..yeah..i crunched the numbers..and..uh..what jim said! ;)
ryan

Thanks for the support Grady. Actually, I have a few more "outside the box" ideas but I don't want to risk any further ridicule! One of them involves using the ice maker from my fridge.:cool:

what about my question.. huh?

You guys are ruthless! This is were some the best ideas come from...:D ducking... You know Edison had an idea....

Yeah, you tell 'em. Einstein's school teacher told his parents he'd never amount to anything because he was dumb! Or something like that.

If conventional wisdom and popular notions were never challenged, there would never be any advancement. I challenge conventional ways of thinking all the time. Ya win some, ya lose some.:)

Oh...I never have any cooling problems in the mountains. The only time cooling becomes an issue is when I'm burnin' up the track on a hot day. That's the scenario I had in mind when I was trying to think of a way to cool the thing down some more. I want to keep the stock front valance so a front-mounted oil cooler is off the table.

I'm probably going to try the Rubbermaid Solution this summer just for giggles. If it works, maybe Grady and I can put it on a dyno and document the advantages of it on a 3.2 Carrera.

And Ryan....unemployed? Never! I'm just, um...resting between jobs.:p

Einstein, Da Vinci and the Wright brothers were in the first group.

My Dad always drove Detroit V-8's. One thing he told me, when teaching me how to drive, was to turn on the heater full blast if I'm in a situation where the engine is heating up, that this might slow the temp.rise untill I could stop safely and see what the problem was.

I know it worked in his 51 Olds 88, because it happened to me and it got me to a country gas station 10 miles or so down the road w/o burning up the engine. Seems to me that might work even more effectively on an air/oil cooled engine.

Boxes
 

"Genius is one percent inspiration and ninety-nine percent perspiration." Thomas A. Edison.

Edison tried all kinds of stuff "outside the box" . .. and threw it in the bin.

There is a difference between discovery and engineering, BTW. Both methods may lead to a solution, but, the engineer is well versed in previous discoveries . .. AND how to optimize their effect(s). --That's a pretty big box!

island, that's the first post from you I recollect seeing in a helluva long time! Have you been hibernating?

Good to see it,

ianc

thx for reply.

Have you ever checked your spark plugs after these hottie runs ?
If not it may be advantageous to monitor them ?

Personally I'm combustion neurotic in a learning sort of way.

also another oil cooler can go under left fender.

:)thanks.
Just waaayyyyy too absorbed in too many projects. Busier than I want to be.

. .and I'm really kicking myself for not having time to see all those cool engines at Waynes open house. You Californians have got it good!

On our air/oil cooled motors, this could actually hurt. The air for the heat comes off of the front of the fan shroud, so turning on the heat will reduce the amount of air going over the heads and cylinders, although I suppose it may cool the exhaust (moot point). On earlier cars w/o an auxiliary fan, this effect may be more pronounced, because air is being drawn from both sides of the motor.

To keep the motor cool when temps are rising, Grady Clay has suggested keeping the rev's up to keep a large amount of air flowing over the cylinders and heads. A front mount cooler is really key in this situation so that you can use speed (and reduced engine load) to reduce temps, on cars w/o front mount coolers it is hard to reduce oil temps once they have risen, because the engine mounted cooler is all there is.

you and me both, buddy..SmileWavy
ryan

Air is always being blown through the heat exchangers; its path is determined at the heat flapper valve. If you have the heat on, the air is blown into the cabin, assisted by various blower fans. If it's off, the hot air is exhausted out the bottom of the car at the valve. There is no throttling mechanism at the fan shroud. Granted that if the blower fans are on, more air will be drawn through this route, but cooling the heat exchangers has a beneficial effect on engine cooling as well.

I read this too, but God help me, it may be the one time that I dare disagree with Grady. My experience shows that with increased RPM's, so come increased engine temps, so you don't really gain much. I believe Ryan tried this at Grady's suggestion before he fitted a front cooler (you did do that, didn't you Ryan?), but didn't find any benefit from it in the hot Arkansas summer. Am open to more discussion, and of course, YMMV,

ianc

Banks tech talk
Cool Air Equals Power

Cool air is good for making power, but could hot air be even better?
http://www.bankspower.com/tech_coolair.cfm
http://www.bankspower.com/tech/cool-...v10-engine.jpg
The Banks Super Scoop, as shown on this Ford V-10 gasoline engine, provides both cool air and a mild ram-air affect. The Super Scoop also incorporates a water drain to separate any rainwater from the airflow entering the scoop.

Greater fuel than should be necessary for power will cool the heads. It's not so much that the fuel absorbs heat as we would simply think. It's that the greater fuel slows the speed of the flame combustion event producing power at the piston. This could also be created by retarding the ignition timing instead of dumping fuel. So instead of cooling the heads from greater oil cooling a wrench could install maybe $8k of EFI.

Meanwhile hot heads at high hp output makes denotation a possibility. Burned exhaust valves is bonus coupons.

Grady's thoughts relate to cooling the heads. If it can't be done simply by greater air flow then it has to be done another way.

I think, technically, it's both. After all, the car isn't going to last long without either an oil cooler or an engine fan, right???

And what about cars that have a radiator and an oil cooler??? Are they both water cooled and oil cooled as well???

Ok, this thread is getting too philisophical for me. ;)

It's simple. You need combustion for power. Combustion needs an environment. You engineer the environment.

>"The world is divided into two groups: those that believe in the impossible >and those working on the improbable. Pay attention, so you end up in the >second group."

Now's a fun time to point out that thermodynamics only applies to systems in equilibrium... and thus definitely not to our cars. In a non-equilibrium state there are plenty of examples of the "laws" being broken. Keep the ideas coming Dave!

Babak

hi ian...yes, i tried this last summer and you're correct..it didn't work. driving the car in 4th gear instead of 5th saw my temps creep up..how much so, i can't recall off the top of my head.
ryan

ianc,

Pelican kobaltblau and I are going to repeat ryan’s experiment this summer. I’m going to measure the head temperatures and the temperature of the oil as it is first pumped out of the engine. We are going to try this with fairly controlled road conditions and on track.

Aside from the speed issue I want to have some quantitative data using the Rubbermaid Solution.

Once we have that repeatable, Andy wants to change the crank pulley to turn the fan 1.82:1. We will then repeat the measurements.

Best,
Grady

Hi,

Just to add to the quote contest:

One should always keep an open mind, but not so open that the brain falls out.

>Only if you fail to define a control volume.

Jim, did you know Jarzinsky when he was at Los Alamos?

grady,
looking forward to the results of your more controlled study. btw, i never did change my fan ratio..of course it being winter, i'm happier with my 'slower fan' for the time being. :) but just wait until july..then august..:(
ryan