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Discussion Starter #1 (Edited)
While I'm on the subject of CAIs with my last couple of posts I thought I'd start a thread with this head-in-the-clouds idea I had a while back.

Can you route some piping from your A/C ducts to your CAI? Like, say cut a hole in the CAI near the filter and route some more pipe from the A/C duct to the hole and blow super cold air directly into the intake (while literally closing off the ducts to the vents to get all the air from the A/C fan to the intake)? I wonder what benefit that would have. I guess the extra power gained by the colder air would be offset by the extra strain the A/C compressor puts on the engine, kind of like that supercharger inefficiency effect.

I don't know. I thought it was cool (pun intended). Let's see some feedback from someone who knows what the hell they're talking about.
 

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Doodeee doodee doodee doo
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i don't know what i'm talking about, but...

your problem would be that the AC runs at a constant speed, and you would want to keep from choking the engine with too much air at idle. tried to figure the same thing out before, but the best i could figure is that you'd have to have a non-exclusive intake pipe... (er, the air would go into the car or somewhere else when the engine is idling.) ... so the most you could expect is a CAI effect at low speeds... i don't think it would be strong enough to count as supercharging though.

besides, what happens if you're running your ac and fan at full blast while your engine revs up to 7000? won't that kill your compressor?

why don't you try it? if it works, hell, tell US how to do it! :cool:
 
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Car is slow enough with the air off. Why turn the air on and make it slower?
 

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Discussion Starter #4 (Edited)
The idea was the increase in power from the really cold air from the A/C. The problem was whether the increase in power would be offset by the fact that the A/C compressor robs the engine of power, like a supercharger that runs off the engine belts. It provides power but steals power at the same time. That's what I meant. I think you misunderstood me. It's not a supercharger, it just brings literal meaning for the phrase "cold air intake." Cold air, right from the A/C, but whether or not the increase in power is offset by the loss in power from the running A/C compressor is the big question.
 

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Doodeee doodee doodee doo
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okay, question now is: how would you connect it and still make the car usable? would you have to poke a hole in the firewall, or would you run the tube straight from the compressor/fan? seeing as how its on the underside over on the right, where would you route the airtube?

there will most likely be a big change in the way your engine runs, but there is still the problem of the fixed fan speeds. plus, you have to find out what the compression rate of the AC is.
 
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Umm...if you want a cooler, denser air charge, wouldn't it be easier (and less expensive) to just install an intercooler into the air intake ducts.

No A/C parasitic losses either!

If you really want to get crazy, set up an injector to spay alcohol on the intercooler. The evaporation will draw a ton more heat out of the intercooler than just plain airflow.

Jeff
 

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dont forget u got to compress the air also
wont work
just spray your cai with this spray that freezes shit up:)
 

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Discussion Starter #8
I guess it's too impractical to actually accomplish but I thought it was a neat idea. Isn't that how most inventions are made? Some tool thinks up some crazy idea that everyone laughs at then when it works they go, oooo, ahhh.
 

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DON'T DO IT!

Hey dudes, FINALLY SOMETHING I KNOW SOMETHING ABOUT!! well anyway, sounds like a ood idea BUT in short it isn't, let me explain....
I had a mate who came up with the same idea and went ahead with it, it did work, in fact it worked quite well with a fair bit more power, especially on hot days. This is where things went bad... After having it in for a few months we went for a cruise down south for a few days, it was quite hot and the car was running good and we were passing this car but when we had done passing and he took his foot off the gas, it kept going. What had happened was that the cold air had caused ice to form around the throttle butterfly and he had jammed the throttle full open. It was damn lucky it was a manual cos he just popped it in neutral (let it rev it's nuts off) and hit the brakes and pulled over to the side. Long story short, save yourself the time, don't do it.
 

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Discussion Starter #10
That's awful. Maybe we can comprise a way to keep condensation from freezing on the throttle plate.

Electric heating pad wrapped around the throttle body? :D
 

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Re: DON'T DO IT!

i_wanna_riot69 said:
Hey dudes, FINALLY SOMETHING I KNOW SOMETHING ABOUT!! well anyway, sounds like a ood idea BUT in short it isn't, let me explain....
I had a mate who came up with the same idea and went ahead with it, it did work, in fact it worked quite well with a fair bit more power, especially on hot days. This is where things went bad... After having it in for a few months we went for a cruise down south for a few days, it was quite hot and the car was running good and we were passing this car but when we had done passing and he took his foot off the gas, it kept going. What had happened was that the cold air had caused ice to form around the throttle butterfly and he had jammed the throttle full open. It was damn lucky it was a manual cos he just popped it in neutral (let it rev it's nuts off) and hit the brakes and pulled over to the side. Long story short, save yourself the time, don't do it.
I find several flaws in your story.
1. I ain't never seen AC blow air so cold it would form ice, especially AC on a 4 cyl engine.
2. On a hot day like you described under hood temps get way over 100 degrees
3. TB has coolant hoses running thru it, to prevent TB plate from freezing during the winter
4. You will loose more power with AC on coldest setting, then gain with cold uncompressed air setup. I live in New England and drove at night during 10 - 20 degree weather with HS CAI. While gains where noticeable then on regular warm day, it wasn't any thing spectacular.
 

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either way this has gotten a good amount of people thinking about it seriously and to me that's pretty good, if someone could extrapolate a setup which acts in a similar way gives a reasonable boost in power yet isn't in the same price range as a turbo, well it'd be good, the more people thinking the closer everyone is.
 

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Discussion Starter #16 (Edited)
I got it.

Tap into the tach system. Replace the A/C fan with a variable speed fan that will increase the fan speed as the RPMs go up and decrease it as the RPMs go down. I'm sure the stock fan has plastic fins, so find an aluminum one. I don't care so much about getting positive PSI numbers like a turbo for pressurizing the intake charge because any N/A engine runs at 19 inches of vacuum anyway so there's no need to force the air in. Just slow the fan down at low RPMs so you're not trying to shove in so much air, but speeding up the fan to let the cold air keep up with the higher RPMs. Well-engineered CPU fans for computers have variable fan speeds for temp changes on the die, why not be able to do it here? I'm sure it can be done somehow. If the tach guage can read engine speed, why can't a fan?

Remember guys I wasn't trying to invent an A/C turbo or something like that, I just wanted to take CAIs a step further and find a way to get the intake charge super cold. My original post said leave the CAI itself alone, but just fabricate another tube that injects more cold air into the CAI system. I didn't mean for the A/C to be the only air intake.

Relocate the A/C compressor to its own power source? If you can do that, run multiple compressors? Trunk mounted A/C?

I don't know dude, I'm just throwing out crazy ideas. None of it makes sense. This is fun anyway, keep thinking about it.
 

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scotts link

something to think about on scotts link.

there is a guy here in Austin running the chevy cyclone truck and he puts a block of dry ice wrapped in a towel on his intake as well as his IC befroe he drags and he claims it works.

Could it be possible to get plastic tubing and wrap your CAI? Then hook it to a small water pump and connect it to a small ice chest full of ice cold water? this would lower the temp of the CAI there for the air would actually lower as well.

The A/C Turbo has been on my brain for a while as well but you really dont need to run all your vents in to the CAI just have a supplemental hose into the cabin with a filter near your floor vent and when you want turn on the floor vent and let it suck in the air it needs at a cooler temp than the outside air all you would need is a 1 1/2"or 2" tygon tube and a small filter (to be safe)and run it through your fire wall.

Dont know just thought I would throw in my two cents as well
 

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niky said:
it would STILL be colder direct from the AC. And we don't want to redirect all the air, maybe just feed off the stream.
That won't work.

Follow the link in my previous message and read the posts by morepower2 and bahearn for more information.
 
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