I see a silicone air intake coupler that replaces the acccordian style rubber one from GM. It claims to smooth out air flow and increase volume.
Is this just a gimmick (which I assume it is) or any real advantage to add this to a stock system?

 

From what Ive heard the less turbulent the air the better the MAF is supposed to work. Unless you have other mods though I probably wouldnt get one unless you just want it to look a little nicer. It seems to work better on after market CAI's for fitment in my experience.

 

i just bought one, not installed yet. i have an attack blue filter and also a ported throttle body, so wanted to finish it off. I'm sure it won't work any miracles, but hey...y not?

 

The MAF is ahead of the coupler on an LS3 so it won't smooth the air out any for that, it might smooth it out going into the throttle body though.

 

And the hose can be bought at ANY hydraulic hose shop

 

What is the diameter of coupler?

 

No. The size is different on each end.

 

Actually, the MAF works better if the air is turbulent. If you run the numbers, you'll find the air flow is either turbulent or transitional anyway, not laminar (which you don't want).

 

It's Sunday, I'm lazy,and I don't feel like "running the numbers". Since you made the statement "Actually, the MAF works better if the air is turbulent" why don't you publish your "running the numbers" to enlighten us.

From Jegs website. The Facts about Cold Air Kits

Does your application require a "Cold Air" calibration? This page will answer that question, as well as educate you about how a cold air kit will affect your mass air meter.

A cold air kit is a simple and effective way to increase horsepower. Cold air kits direct cool air from outside the engine compartment to the engine's induction system. Our "Cold Air" mass air meters have a special calibration meant to be used with these kits. Our "Cold Air" meters also come equipped with an air inlet screen. This will be explained later on this page.

First, lets go over the different types of cold air kits:

Type 1: The first, and most common cold air kit, has an elbow attached to the front of the mass air meter. This elbow directs cold air from outside the engine compartment into the mass air flow meter inlet. Our "Cold Air" meters are specially calibrated for this type of cold air kit. If you are using this type of cold air kit, you should order a meter with a "Cold Air" calibration.

Type 2: The second type of cold air kit positions the mass air meter out in the fender well, with a conical filter attached directly to the front of the mass air meter housing. This type of cold air kit requires no special calibration for the mass air meter. If you are using this type of cold air kit, you should order a meter with a normal calibration.

Type 3: The third type of cold air kit consists of a conical filter attached directly to the front of the mass air meter housing, and an enclosure around the filter. This enclosure is ducted into the fender well, and supplies cold air to the outside of the filter, which will be drawn into the filter, and of course the engine. This type of cold air kit requires no special calibration for the mass air meter. If you are using this type of cold air kit, you should order a meter with a normal calibration.

Type 4: The forth type of cold air kit is not really a cold air kit at all, although they are commonly advertised as such. These kits consist of a conical filter attached directly to the front of the mass air meter housing with no ducting of any kind to retrieve air from outside the engine compartment. Since the engine is still drawing air from the engine compartment, this can in NO way be considered a "cold air" kit. This type of kit requires no special calibration for the mass air meter. If you are using this type of cold air kit, you should order a meter with a normal calibration.

Mass air meters with special calibrations intended for cold air kits have existed for quite some time, although they have commonly resulted in a rather high rate of return. That is, customers commonly return them as "defective" due to idle and drivability concerns. We've solved this problem. Our testing has revealed that this is not due to the meters actually being defective. The problem lies with the variables associated with a typical installation. That is not to say that the customers have installed them incorrectly. The fact is that there are too many factors that are not under our (or your) control.

These factors include:
1. There are numerous different shapes of inlet elbows being sold by the different cold air kit manufacturers. The shape of the elbow greatly affects the calibration of the meter.
2. The distance of the elbow from the inlet of the MAF meter affects its calibration.
3. The orientation of the elbow (in other words, the direction the elbow points in relation to the meter) also affects how the meter should be calibrated.

We've discovered a way to negate these factors. As mentioned earlier, our "Cold Air" MAF meters are shipped with an air inlet screen. If the meter has a flange, the screen is incorporated into a gasket to be used between the flange on the front of the meter, and the flange on the cold air kit. If the meter does not have a flange, then the screen is incorporated into a "band" that will be installed on the front of the meter. The silicon hose that attaches the cold air kit to the front of the meter is to be installed over this band.

So why the screen? Our testing has revealed some interesting facts. Let's look at the factors that affect the meter's calibration again:

1. There are numerous different shapes of inlet elbows being sold by the different cold air kit manufacturers. The shape of the elbow greatly affects the calibration of the meter. --- Here's why... The use of an elbow causes the air to "roll" as it comes around the turn. This rolling air creates pockets of turbulence that pass by the MAF sensing element. This turbulent air creates an inaccurate voltage output, which is interpreted by the PCM (engine computer), as an inaccurate amount of intake air. Other mass air meter manufacturers have attempted to solve this problem through "Cold Air" calibrations, but the fact is, there are too many variables for that method to be consistently effective. Different elbows with different shapes will cause different levels of turbulence. The air screen solves this problem. As the turbulent air passes through the screen, the air is "smoothed", eliminating the turbulence. This allows the MAF meter to generate an accurate voltage signal to the PCM based upon an accurate measurement of the air mass passing through it.


2. The distance of the elbow from the inlet of the MAF meter affects its calibration. --- The longer the distance between the elbow and the MAF meter, the more time the air has had to settle down. Again, this factor is rendered irrelevant by using the inlet air screen.


3. The orientation of the elbow (in other words, the direction the elbow points in relation to the meter) also affects how the meter should be calibrated. --- The direction of the elbow determines the direction of the "roll" effect in the air. MAF meters supplied by other manufacturers are greatly affected by as little as a few degrees in rotation of the direction of the elbow! Again, since the screen eliminates this turbulence, the direction of the elbow has no significant affect on the MAF meter's calibration.

Other Facts of Interest:
1. You might assume that the screen would be somewhat of a restriction. Our testing has confirmed that, in "cold air" applications, the meter will actually flow considerably more air with the air screen than without. When turbulence is present, the air is scattered in many directions, which will serve to fight the flow of air through the meter. The air screen removes this turbulence, allowing the smoothed air to flow more freely, which results in improved air flow.


2. Due to the smoothing effect of the air screen, signal "noise" is also virtually eliminated. Other companies MAF meters calibrated for use with "cold air" kits will have an undesirable amount of this "noise".

Some additional reading....http://www.pvca.org/PVCA_A_MassAirFlowSensor.asp






Since Fuel injected engines are so sensitive to air/fuel ratio, knowing how much of each component is entering the engine at any given time is essential. This is possibly the most important measurement inside the PCM. A mass air flow sensor is used to determine the mass of air entering a fuel-injected engine, and is necessary for the engine control unit (ECU) to balance and deliver the correct fuel mass for the fuel injectors.

The MAF is located between the air filter and the throttle body. In the simplest of terms, a mass air system uses a sensor that directly measures air mass flow into the engine. How you ask, the MAF uses a very fine wire electrically heated up to a temperature above the ambient. Air flowing past the wire has a cooling effect on the wire. As the electrical resistance of most metals is dependent upon the temperature of the metal, a relationship can be obtained between the resistance of the wire and the flow velocity.

There are two basic types of MAF sensors; one that uses a standard 0 to 5 volt output, and in the case of the Corvette (and all GM engines) a 0 to 12,000Hz frequency. In either case, both work well.

If you have a keen eye, you will notice two things about the MAS. First, most MAF’s are sized to be slightly smaller than the rest of the inlet plumbing. This is an effort to control velocity and increase accuracy. Second, there is a screen or flow element in front of the sensor. This flow element is designed to reduce turbulence entering the MAF and promote laminar airflow and accurate readings. A common mistake made by most enthusiasts looking for extra power mistake this laminar flow element for a genuine restriction and removes them. Benefits of removal rarely justify the loss in metering accuracy and throw the calibration out of whack.

Another common mistake the search for extra horsepower is replacing the air filter or adding a cold air induction system. A very important change is made when we add/change these components. Even though the same amount of air may be flowing, the frequency reading out of the MAF to the PCM may change slightly. This is possibly the most important measurement inside the PCM. Everything that happens in the PCM is based on grams of air as measured at the MAF. Getting the MAF right is a critical step in keeping your fuel trims closer to zero, having better drivability at part throttle and hitting the right AFR at wide open throttle. Technically, after making these changes, the MAF, AFR and timing should be recalibrated.

The MAF can be tuned for partial and wide open throttle and will increase drivability and provide crisper throttle response. There are two sources that the vehicle’s computer uses to determine how much fuel is injected based on air flow; the Mass Air Flow and VE (Volumetric Efficiency) tables. The object is to modify these tables so that there will be less error for the computer to trim out with the long term fuel trims. However, we C6 owners don’t have a VE Table. The C6 is equipped with a “virtual” VE table, which obviously cannot be tuned accurately. However, you can set up MAF to strictly use the MAF sensor as the only option to tune with. (That’s another article).

I spent the better part of an afternoon calibrating my MAF for partial throttle. It is recommended that steady state testing like this is done on a dyno for best (faster) results, but you can do this on the road. You won’t exceed 40 MPH for the most part, and it’s definitely cheaper. This is a process of collecting data, making adjustments, collecting new data and making more adjustments. You can achieve better fuel trims by performing this process over and over again, but keep in mind you can reach a point of diminishing returns.

MAF calibration for wide open throttle tuning should be done on the dyno for best results. The purpose here is to ensure the MAF sensor is calibrated properly for WOT operation. WOT operation is generally referred to as “dynamic” airflow, as it is constantly changing due to the WOT and the rising rpm’s. However, I have done the data collection at the drag strip and have made some minor changes. To do this properly, a wideband O2 sensor is required to gather important A/F ratio data. Doing anything that leans out fuel ratios without your knowledge can be very hard on valves and pistons.

Even more info....http://www.steeda.com/news/steeda_ne...air-intake.php

Turbulence

This is perhaps one of the MAJOR differences in Cold Air Intakes as it is most often overlooked by other manufacturers – it is what separates Steeda from all other systems you can buy. Any bend, restriction, rough surface, or change in the inlet tube diameter will create a change in flow turbulence. Excessive turbulence hurts flow velocity which, in turn, makes it more difficult to pack air into the cylinder. Also, turbulence in front of the MAF sensor can cause erratic airflow signals to be sent to your engine's electronic control module – resulting in an incorrect air/fuel mixture being delivered into your engine. At Steeda, we minimize turbulence with the design of our billet aluminum MAF tube, velocity stack, and intake elbow to ensure that the airflow into your engine is as smooth as possible. Even the air filter has a converging spike to reduce turbulence. We go to these extremes because you deserve the best!

 

Well, I don't feel like rerunning the numbers either. But since you don't believe me, you really should.
What most people don't understand about fluid flow is that laminar flow is not even all across the duct. Flow is near zero at the walls, and increases as you get closer to the center. The distribution changes with velocity. In turbulent flow, the velocity distribution is much more even across the duct.
I won't get into the screen vs. no screen argument, but I think the screen serves to break up any resonances across the tube to even out the DISTRIBUTION of the flow at the maf.
The discussion about elbows is largely addressed at fixing the velocity distribution across the duct.

 

What is the size?

 

About 3 3/4 and 4 inches.

 

I was thinking about this myself, replacing the waffle type duct on my 2005 C6 with a smooth one. Is there an advantage over looks and if so where can you buy one. Mine has some type of sensor in it so it will have to have a place for that also.

Yes I have read the post but some say it helps some say it does not, so what is the bottom line?

Thanks guys and girls.

Rick

 

 

The proper size is 5"long x 4 1/2"oval x 4" @ throttle body. BTW, I made one first, took a 250 mile trip, & increased my gas mileage by two miles per gallon. The car was on cruise @ 70mph. Just as I normally do on this trip every month. So apples to apples,& very precise, no funny business. A new aftermarket coupler is on the way to be installed this weekend. EBay sells them in red & black for $34 - free shipping !!!!

 

This theory is really wrong when based on a MAF sensor and a running engine. You do not want ANY turbulence. The maf sensor is reading airspeed through the intake which in turn is calculated into G/SEC in the ECU. If the air is turbulent you will get a mis reading of the g/sec and the car will start fueling erratically which in turn will also cause the car to start surging as engine torque is increased and decreased at a fast rate. In the automotive field turbulence is not a good thing unless it is inside the radiator.
Justin

 

I read all of the theoretical air movement info. But after the MAS comes the curved duct. And then the air runs smack into the accordion connector. Now it gets moving in all directions again before entering the throttle body. Don't you agree that all around smooth surfaces inside the aftermarket reducer duct will tend to keep the air flow at a more constant speed & uniformity to the 8 cylinders it is trying to keep the same. You can't make any electronic adjustments after the MAS makes it's final readings, so any mechanical help after that has to do some good. You agree or not ?

 

been looking for one of these to replace the accordion looking tube. cant find it on the auction site.

 

You have to type in the following....corvette c5 smooth air coupler....there is none for a c6 as the sizes are not the same. I can't see buying the more expensive black bell style, because the $33.95 one looks smoother & a more constant taper. Good luck with it.

 

The item # on EBay to type in is....141098583082....$33.98...Red or Black