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Old 04-14-2006, 07:10 PM   #37
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Quote:
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Leaner mixture gives more power?? Freeing up h orse power?? Go for a run around the block. Now tape your mouth closed and plug one nostrel and go for the same run. That's the same effect the engine has when breathing through a resticted air-intake. Get back to the basics gang, and richer mixtures give more power.
a leaner mixture will give more power, try running around the block with your mouth full of water & then try it without, which is easier?

the combustion of air & gasoline causes the rapid expansion of gases (fumes) that cause the piston to be moved down, the more gases in the camber already the less the have to be "created" by combustion. That's why Turbos & S/C can work on a un-tuned car, but to keep a Soitch AFR you have to add more fuel to match the amount of air. it all has to do with compression, more air in the camber, then it can compress, In short, a leaner Stoich mixture will give more power.
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Old 04-14-2006, 07:41 PM   #38
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My experience with racing (granted it was motorcycles with carbs not FI), was that you would run the engine as LEAN as possible, without detonation.
That's why we did repeated plug chops. A lean mixture meant more horsepower. Is modern FI running on some principle I don't understand????? Please note ........ I didn't tune the engine, I only rode the thing.
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Old 04-14-2006, 11:01 PM   #39
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Stoichiometric AFR or 14.7:1 gives the best performance with the lowest produced emissions. The best economy can be obtained with AFR around 16 to 18:1. Leaner mixtures produce higher temps, burnt pistons and valves. The best power is usually obtained with AFR around 11.8 to 13.0 and that's the facts. More fuel, more power.
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Old 04-15-2006, 03:14 AM   #40
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more fuel only results in more power, because you can shove more air into the combustion chamber to burn the fuel. that's the basis of my understanding. too much fuel, and it doesnt get fully used in the combustion chamber, and you lose power. an 11.8-13 AFR sounds like something that a car with forced induction would want to be tuned to, ideally, to provide some headroom for detonation on a hot day, etc etc.

yes, leaner mixtures result in higher temps. but burnt pistons and valves, no. only if it is TOO lean, not tuned properly, and running outside of the parameters set by the ECM. when you run too lean and get detonation, the knock sensor picks that up and retards your timing, so you lose power.
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Old 04-15-2006, 08:05 PM   #41
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I am not referring to what the sensors and ECM do etc. The ECM will strive to keep to 14.7:1 which you should know is the best AFR for performance and emissions. I am only stating the fact and not looking for any arguments that a richer mixture produces more power. Thats why performance cars smell like a gas station when you are next to them.
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Old 04-16-2006, 08:59 AM   #42
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We're a little off topic. This is about the cold air intake right. I'm guilty of it too, but we should be posting about any new info regarding cold air intakes.
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Old 04-16-2006, 11:07 AM   #43
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I will be making a custom one for mine that will kinda look stock but it won't be.

Like this


there is a tube that you fabricate to run down and suck in the air coming in fender and then you upgrade the tube going to the intake to a silicone one that drops temps and is bigger to suck in more air.

Last edited by birdy; 04-16-2006 at 11:32 AM.
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Old 04-16-2006, 01:37 PM   #44
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Right on Birdy! Stick a K&N in there when they are available and remove the HC screen. Also you can replace the silencer mesh behind the TB with an O ring, or just cut the mesh off of the existing one.
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Old 04-16-2006, 01:47 PM   #45
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I will be making a custom one for mine that will kinda look stock but it won't be.

Like this


there is a tube that you fabricate to run down and suck in the air coming in fender and then you upgrade the tube going to the intake to a silicone one that drops temps and is bigger to suck in more air.
Cool! Let us know how it works.
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Old 04-16-2006, 11:21 PM   #46
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what is the impact of the different temperatures on a cold air intake?

can cold air be too cold?
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Old 04-17-2006, 06:27 AM   #47
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what is the impact of the different temperatures on a cold air intake?

can cold air be too cold?
No, not really. Colder air is denser, so more air can get in the cylinder if it's colder. That's why a snow machine runs so much better when it's -30 than when it's -10. Someone else could prolly put it a little more technical. I'm a little groggy this morning.
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Old 04-17-2006, 07:43 AM   #48
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Nice Idea birdy, I like the Short Ram Intakes myself, & a (functional) hood scoop, but just a small one.
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