cold air...?
#26
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That's not an implication, it's an assumption that could only be made by a very ignorant and/or stupid person. I have trouble believing that many people are stupid enough to believe a "cold air intake" will reduce intake temp below ambient. I know there are lots of idiots modifying cars, but only a very small and insignificant number of people are going to think that, and who cares about them anyway? The vast majority of people are going to realise that "cold" simply means "colder than the engine bay". I've certainly never seen anyone in this forum suggest they thought anything else.
At least in the 80's the high performance filters were marketed by their improved flow rate, which is actually true in almost all cases, despite being barely measurable on an otherwise unmodified engine.
Yes, those lame internet tests tend to show that. Fortunately, that correlation is actually quite applicable for the majority of the readers. I guess it just bothers me that all other aspects are ignored while the articles focus on their simplistic agenda.
#28
I'm a boost creep...
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Yes, those lame internet tests tend to show that.
#30
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The implication is that the aftermarket "cold air intake" will supply the engine with colder air than the stock intake.
Designing the right cai placed in the right spot should work better then the complete stock intake system. Im not saying you will gain much or anything to notice, but in theory, should work better at getting the outside air into the intake then the stock system.
#31
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Also, my original quote in this particular thread was "The implication from the naming convention is that an aftermarket "cold air intake" would supply colder air than the stock intake. With a Honda, that may be true. With an FC RX-7, that is not true".
The tests I'm referring to are far from what I'd call lame. I'm referring to the ones done by Autospeed. Using sensitive pressure testers (a water manometer or a Magnehelic gauge) to measure the pressure drop at various points along the intact tract is a perfectly valid test. What exactly is your criticism?
2. Their testing does not follow SAE guidelines.
3. Their testing assumes stock engine flow rates.
4. Their testing of only one parameter while ignoring and not even controlling the other parameters is just plain lame.
While I understand that magazine type articles need to be brief and dumbed-down for the general public, and it is not practical for the journalist to consult a scientist or engineer in the subject's field, it does not mean that I will give them the same value as an SAE paper or similar well-written technical journal.
At least the Autospeed articles are not as bad as that hideous Revspeed air filter infomercial running around the internet.
Yes.
#32
I'm a boost creep...
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2. Their testing does not follow SAE guidelines.
3. Their testing assumes stock engine flow rates.
4. Their testing of only one parameter while ignoring and not even controlling the other parameters is just plain lame.
Your comments are very broad and don't actually explain what's wrong with the way the testing was done. Are you saying the results are worthless? Are you saying they proved nothing? So many people make baseless claims about the effectiveness of the mods they perform. You should be encouraging people to test their work, not rubbishing the practical methods for doing so.
Let's not forget that I brought up these tests because they all shows that the pressure drop through the stock filter was tiny compared to the rest of the system. Are you disputing that? Do you have better evidence to the contrary? Evidence the SAE would accept?
While I understand that magazine type articles need to be brief and dumbed-down for the general public, and it is not practical for the journalist to consult a scientist or engineer in the subject's field, it does not mean that I will give them the same value as an SAE paper or similar well-written technical journal.
#33
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The stock system works just fine. Its main problem is that it has some pressure issues just like every other stock intake, as already stated by NZConvertible. The pressure issues become more of a problem as the engine's flow rate increases. For those of you reading this who do not have a strong background in this subject, you can think of it the same way a square-shaped car would have no problem traveling along at 10mph, but when you try to take it up to 150mph the drag is going to become a big problem. Just like there is no point in adding fancy aerodynamics to a 10mph vehicle, there is no point in adding a fancy intake to an engine with a flow rate that is within the efficiency range of its stock intake system.
I would like to see a comparison of the pressue drop in the stock intake vs a well designed custom cai on a stock port n/a engine with stock exhaust and a stock port n/a engine with a high flow exhaust. Considering with a high flow exhaust, the engine is able to injest more air, the pressure drop may increase to a point where replacing the stock intake setup may actually give you a little gain.
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