Intake

[cookie]

we should get lost? OK.

[slo5oh]

a quick google search... and

 

Stolen from http://www.newton.dep.anl.gov/askasci/eng99/eng99234.htm

 

 

All substances, gases, solids, and liquids, including water, are compressible. Some substances just require more pressure per change in volume to compress than others. The numerical value of the compressibility depends both on the temperature and on the pressure too. That is how hard you have to squeeze at one pressure to obtain a certain fractional decrease in the volume is different than at some other pressure. The same for two different temperatures. Under most "normal" lab conditions however solids and liquids are usually considered to be incompressible.

 

 

Some of you seem to be experts on the subject. Some seem confused. Inside your combustion chamber will be both air and fuel. If a little water slips in you will be fine and it will turn to steam either before, during, or after the ignition of that cyl. If more gets in it will "bog" your engine down and the mixture will not ignite correctly. If quite a bit gets in you will seize the engine. It takes quite a bit. Depending on the size cc of the heads, and how the piston is seated in regards to the top of the block you will have more or less space known as your combustion chamber. If you exceed the size of your combustion chamber you will hydro lock. I've personally poured a mixture of brake fluid and water down a carb on a chebby 350 to clean the carbon from the tops of the pistons. I wouldn't do it now a days since it would probably destroy the o2 sensors. But, holding my idle at 3000 rpm I poured an entire 44oz cup down the carb in about 60 seconds.

 

 

And as for an exhaust valve being bent by this situation... It does sound far fetched, but I've seen stranger things.

[legacy2.5]

an internal combustion engine will not make enough p.s.i. to compress water.

[THAWA]

While that may be true, it doesn't make water incompressible

[slo5oh]

While that may be true, it doesn't make water incompressible

I repeat...

Under most "normal" lab conditions however solids and liquids are usually considered to be incompressible.

So unless you have one of those machines designed to turn coal into diamonds... water can not be be compressed. I don't care to hear about scuba diving... heavy water... whatever... for those of us not related to superman water can not be compressed. Even if you made your engine out of titanium you still could not compress water with it.

[Nug]

I'm chiming in...

 

Valves won't bend because a cylinder is full of water.

 

I could see a valve warping because of thermal shock from water hitting it, especially exhaust valves.

[THAWA]

So unless you have one of those machines designed to turn coal into diamonds... water can not be be compressed. I don't care to hear about scuba diving... heavy water... whatever... for those of us not related to superman water can not be compressed. Even if you made your engine out of titanium you still could not compress water with it.

You can say that all you want, you can't change the laws of physics, water is compressible.

[Chip]

All this talk about how the engine might destroy itself because of water entering an aftermarket intake makes one wonder why they'd want an aftermarket intake in the first place !

 

A cold air intake will NOT give you the power gains they advertise...Not even close. You will NOT save enough gas to get a return on your investment.

 

If cold air intakes were such a great modification, the car companies would design/install their own.

 

Don't be suckered in by the "10-15HP increase" claims. Save your money and get something more useful....like fuzzy dice.

[oddcomp]

no offense chip.. but can i ask how much background research you have done

on the topic of cold airintakes and other such items relating to the induction of fuel and air into a motor..

oh and please do not take my poor typing skills as a sign of inteligence

[cookie]

engine to do damage. As someone mentioned before taking a garden hose and trickeling it into the carb used to be a common method of getting carbon out.

Also folks have used water injection to reduce pinging and gain power.

But when you do get enough in it really hashes everything.

The only time I have heard of engine damage is in fording streams.

[kingbobdole]

I'm gonna agree with the last two. Firstly cold air intakes (fair to good quality ones) DO in fact give you good power increases. Also they do give you better milage, but one point about that is that one has to drive consistently to notice such fuel increases. When I first got my intake on the Focus I thought it killed the MPG but in facct my foot had gotten heavier. Secondly, Hyrdolocking is not very common execpt in extreme conditions such as fording rivers or streams. I might make a note though as not all rivers or streams are permenent, all people that drive colorado springs when it rains knows what I mean. The drainage there is bad, not to mention when it rains, it RAINS. Water drops by the barrel and floods everywhere. Just a few weeks ago I was driving through this terrible strom, stuck in traffic. I got to the front of the line to see some joker in a honda hatch thought he would just drive through this puddle. Well, the road had sunk under this "puddle" and he was in up to the windows. Wonder if his engine locked. Ohh and to define "fording", the first thing I thought.

FORDING: Process by which a Ford eventually takes its self off of the streets.

And a ditto on my typing skills.

Phil

[cookie]

it gets to the intake. Old Jeep sixes sometimes saved them selves by having the distributor on the side. If they entered the water slowly and cautiously the electrics would die before the water got to the intake.

If it goes in slow you can drain the water and dry it out ad be fine.

This is the first time i have really thought about bent exhaust valves in flooded engines and on furthur reflection I think you might get them because of the broken pieces of piston, or the fact that when a rod breaks the piston often flies to the top of the bore. If the broken piston hits the next valve that opens it will be the exhaust.

[THAWA]

a cone filter doesnt also increase performance and gas mileage. It totally depends on the situation. And in this situation it doesnt do either. There's a lot of engineering placed behind our intake setup.

[Chip]

no offense chip.. but can i ask how much background research you have done

on the topic of cold airintakes........

I'm sure the automakers have done more research than anyone on air intakes and other "cheap and easy" modifications. Don't you think that if Subaru could get an extra 5-10 "free" HP out of a motor they'd do it ?

[slo5oh]

You can say that all you want, you can't change the laws of physics, water is compressible.

I'm starting to feel like I'm running in the special olympics... even if I win I'm still retarded for arguing with you.

Whatever... you think you can compress water, go ahead and live in your fantasy world.

 

As for the most recent posts.

#1 Yes, you can see gains by using an aftermarket intake (cold air or other) but only if you have increased overall HP of the engine first. All manufacturers spend big $ to (usually) match up everything - intake tubes, intake runners, combusion chambers, intake and exhaust valves, header or exhaust manifold sizes and designs etc to make the most power, performance, and mileage out of the lowest cost parts. If you have built up your engine and are making 50% or more power then OE that's when you can make decent gains with a larger intake tube.

 

Also folks have used water injection to reduce pinging and gain power

This is correct. 1/4 mile guys have been doing this for year... going back into the 70s and maybe earlier. It was common back then for the water injection to leak while the car was off, after several big racers bent rods and destroyed cranks many would pull the spark plugs out if the car was going to sit for more then a couple hours. That way when they jumped in to fire it up it would simply shoot the water out the spark plug hole. Put the sparkers back in and they're off and racing again.

[THAWA]

I'm starting to feel like I'm running in the special olympics... even if I win I'm still retarded for arguing with you.

Whatever... you think you can compress water, go ahead and live in your fantasy world.

the 1990's called, they want their joke back

 

you should feel retarded if you think water is incompressible though.

[Setright]

Cookie, if we are not in agreement, make a useful suggestion or lay down an indisputable theory.

 

Snotrocket's idea of thermal shock is the first plausible one I've heard. Hats off!

 

 

As for the old discussion as to why OE intakes aren't drawing cold air: Well, many of them are! Have you looked under the bonnet of a gen3 Legacy? Air is drawn in from above the grille. Gen1 and 2's drew from inside the fender cavity.

 

Heck, even a Volvo 340 - ca. 1985 - has a factory cold air intake. So it works. And it doesn't mean instant hydro-lock.

 

 

Why then, are some of our Subes drawing from inside the engine bay, and losing potential horsepower? Noise. Some of it forced by legislation, some because it's easier to sell a silent car. Maybe even to save fuel, since less dense air will take less fuel along with it?

[kingbobdole]

Agreed,

That Honduh I drive for work I always pull the intake resonator tube out of the filter housing. Gives me some more power, but damn its loud.

the 1990's called, they want their joke back

wow, thats great. This little side conversation is very amusing to me. not only the lenghts that you two go to, but damn. My opinion, not to spray fuel on the fire but.... anyone that stayed awake during physcics class knows that water and other liquids ARE indeed compressable and not only in labs. Even in an engine right before that rod snaps, the water compresses. Yeah, not much, but it does. heres the home experiment. go get a plastic bottle. fill it with water and cap it good and tight. A 2 litre works best. now.... jump on it. hopefully you had a good cap. What happened? Did the bottle explode? Did the cap fly off?, go get a better bottle. Usually with a good bottle magically the mystical liquid will compress. Not trying to be an rump roast. well... not trying hard at least...

Phil

[THAWA]

thank you, I'm glad there's at least one other person here that actually cared enough about science and the basic laws of physics to pay attention during school.

[blitz]

Manufacturers ARE beginning to include cold-air intakes that draw from the fender well.

 

All too often it's the aftermarket big thinkers that do a lot of the developmental footwork with interesting innovations, then the manufacturers just take it.

 

The three stages that truth passes through:

 

1. First it is ridiculed.

2. Then it is violently opposed.

3. Finally it is accepted as self-evident.

 

Oh well.

[THAWA]

That's so true cookie. And it's not just with automotive stuff. People have been like this since forever. Remember, people used to think the earth was the center of the universe, the sun and all the planets rotated around it, the world was flat, maggots came from meat, there were only 4 elements, etc. It's funny how people are.