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19

Lean ≠ More Air I believe the source of the misunderstanding is in how the term "lean" is being interpreted. A lean mixture doesn't indicate the presence of more air. It indicates the presence of a higher proportion of air compared to fuel (air-fuel ratio, or AFR). Quick example Mixture A has 1,000 g of air, 80 g of fuel. AFR = 1000/80 = 12.5 ...


16

Does this mod ever give a measurable increase in power? tl;dr: yes, sometimes it works well. But... Your picture is a good illustration of some of the problems with just saying "cold air intake" and expecting that to mean the same thing to all people. Let's break down the pieces of the puzzle and talk about how those might help or hurt: Filter: ...


10

It will have no affect on the longevity of the engine or components as long as you get one with a decent filter on it. You'll have to check reviews on different elements to ensure you are getting one which is good. We'll not mention which ones I think are better, as that gets into the realm of both shopping and opinion. In and of themselves, CAI's will not ...


9

MAP = Manifold absolute pressure and is a sensor to measure vacuum, the computer calculates the engine air flow based on the vacuum, throttle position, and intake air temperature. The computer also measures the barometric pressure using the MAP sensor before the engine cranks, this lets the computer compensate for altitude, or how dense the air is. Typical ...


8

Normally the idea is to get more air into the engine using a less restrictive air filter. As an engine is basically an air pump, getting more oxygen and more fuel into the engine usually equals a bigger bang and thus hopefully more power. That said, in order to get a meaningful improvement using a performance air filter, the main restriction needs to be the ...


8

Variable-length intakes increase the pressure of the air entering the intake manifold thanks to a physical phenomenon called Helmholtz resonance. It's also known as dynamic supercharging since it avoids the use of a mechanical device (compressor/blower) to boost intake air pressure. How the Helmholtz does it increase air pressure? Without getting too ...


8

The point is to feel like you've done something cool to your car and freed it from the shackles of The Man/the OEM intake. The primary benefit of Cold Air Intakes is to the bank account of the kit manufacturer, the secondary benefit is your car making a nicer noise, if you like the sound of an aftermarket intake. There's been a few debunkings of CAIs over ...


8

It's not that the catalytic converter can't handle more air per se, it's that running lean increases the temperature of combustion (I actually don't know why, but now I'm curious) and the catalytic converter needs to run inside it's chemical operating range. Something to do with the chemistry that I also don't know. As for advantages for turbo boost and ...


8

Some people think that a cold air intake will generally improve engine performance, allowing fuel to combust at lower temperatures, increasing fuel efficiency. They believe the lower temperature is actually better for the engine. Performance air filters, if you get a good quality one, might typically allow more air flow while reducing foreign particulate ...


7

It depends. Just because an intake can flow more air mass doesn't guarantee that the engine will utilize it. The intake is part of a system of components. The engine produces power by managing air flow into and out of the combustion chamber. There are usually other actors involved: Intake side. Carburetors, throttle bodies, intake manifolds, intake ...


7

The 'floating' intake runners are moved by a mechanism, coupling and decoupling them from the main intake runners to increase the overall length for better low RPM performance. This process was recently discussed here: mech.SE on inlet runner length I don't see that having the extension pieces in the decoupled position would have any effect of the resonant ...


7

I agree with @JPhi1618 that it is related to the MAF sensor. From the picture you provided in your comment, it appears your (really good looking) MSR intake comes with its own MAF sensor housing. I too am unfamiliar with this car, but the MAF housing on your new intake is likely a different diameter than the OEM housing. This causes problems, as your OEM ...


7

I don't have any empirical evidence for this, but would say no for two reasons: An air filter will collect more dust, dirt, and debris until it gets so full that it starts pushing the older dust, dirt, and debris through the filter, which is what you are trying to prevent in the first place. As the air filter collects more dust, dirt, and debris, the ...


7

It all depends on what you mean by getting better. It is possible that, as the very small holes in the filter that let air through start to trap particles, the places where air can get through will get smaller and smaller. Therefore the filter will start to trap smaller and smaller particles. The air filter may get more efficient at filtering, but it will ...


6

First of all by "most production motorcycles" I am assuming commuter level motorcycles used in South and South East Asia its not true that all production motorcycles have intakes facing backwards, its more or less a ergonomics based design decision , some motorcycles have intakes facing 90 degrees to the side. Some have them facing towards the back as you ...


6

The oil stuff is more than likely caused from what the intake pulls out of the crank case through the PCV. If you can get a hold of a couple cans of Seafoam, this should take care of the residue about as easy as you can do it without taking the engine apart. Use the rubber hose to the right of the photo to introduce it into your system. As an engine gets ...


6

Lean operation vs exhaust catalysts: The three-way catalytic converter fitted to gasoline vehicles can't operate under lean engine conditions because the reaction of NOx to nitrogen and oxygen is a reduction reaction, and for this to occur there needs to be a corresponding oxidation. In the three-way catalyst that is the oxidation of CO and hydrocarbons to ...


6

I believe that what @JPhi1618 stated is a major factor in your rich condition: Could the different air flow path cause issues for the MAF which would have been tuned specifically for the stock intake? And that this statement that you made to counter I believe not to be true: BMW uses the same Bosch `MAF` sensor on all turbo cars. I highly doubt they ...


5

tl;dr: your car will be more vulnerable to hydrolock. Don't use full throttle in deep puddles. In the rain, you should be fine in most situations. All that said, you'll still be able to ruin your car if you try hard enough. If you submerge a running car in water, it's going to damage the engine, cold-air intake or not. One of the worst possible ...


5

depends on if you have carburetors or fuel injection If you have a carburetor Cons You will make the bike have a lean condition Backfire on deceleration More oxygen will create more engine heat and this will cause additional wear on components You could burn your exhaust valves Pros You could buy a jet kit and pipe to go with it and get a few extra ...


5

It sounds as though you did suck up some water and were on the verge of hydrolock, but didn't quite get there. I also doubt you have caused any damage to the engine, in fact, you may have inadvertently helped your engine (though I wouldn't suggest you do this again!!!). The extra sputtering may have been a case of the filter on your CAI getting soaked with ...


5

Specifically a foam filter for a lawn mower needs oiled, but just lightly. A foam filter lacks the ability to stop small particles as compared to a paper filter. The oil is added to make the filter "sticky" to these small particles giving the foam filter better filtering capability. As far as major engine damage, probably not. Worst case scenario the engine ...


5

The length of the intake runners have certain affects on the engine operation. For example, longer intake runners are used to improve the bottom end torque (torque at low RPMs) while shorter intake runners will improve top end power (horsepower at high RPMs). The lengths will vary from engine to engine as well as what the goals of each vehicle the engine ...


5

If the prints are just on the seal, I wouldn't worry about it. You could possibly take some gentle cleaner (Windex or Formula 409 or the like which will clean grease) and make it pretty again. It won't, however, decrease the function of the filter in any way. If they got a bunch of oil on the element itself, you might want to think about it. Really nothing ...


5

This is a variable-length intake Variable-length intakes increase the pressure of the air entering the intake manifold thanks to a physical phenomenon called Helmholtz resonance. It's also known as dynamic supercharging since it avoids the use of a mechanical device (compressor/blower) to boost intake air pressure, which means the air enters the cylinders ...


5

A few things to consider if you end up doing this: A longer shaft will reduce the speed that you can safely spin the turbos up to It's got to do with something engineers call rotordynamics, although I highly doubt you would need to spin something up to 125,000 RPM for a turbojet application :) You may also find that the existing journal bearings are not ...


4

If this is the V6 Accord, it very well could be an issue with carbon buildup again. It seems there was a tech bulletin which was issued by Honda about it for the 98-01 Accord and 99-02 Odyssey. I found a pretty write-up of how to get it really cleaned up, as getting it into a good state is quite a bit of a job. Here is where the write-up can be found with ...


4

Doesn't it suck up only as much as engine speed and throttle position allows? No, throttle position and engine load determine the quantity of air consumed. It can be quite hard to understand at first how a naturally-aspirated engine can ingest different quantities of air at the same RPM. Here's what the Engine Management Fundamentals chapter of the ...


4

The manual you linked to explains what they're used for. The AACV is the main idle speed control while the FICD is used to supply additional air to the engine when the AC is turned on. AACV (Page EC-GA-117) This system automatically controls engine idle speed to a specified level. Idle speed is controlled through fine adjustment of the amount of ...


4

Would there be a substantial enough of a horsepower boost to be noticeable? The most you could see from such a modification is 15hp. This would not be enough for the seat dyno to register, unless there are plenty of hemorrhoids to detect it. More then likely you'd see a measly 5-10hp, and then only at the higher RPM levels would this be apparent. You ...



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