My new B-Line Motorsports True Cold Air Intake

[CL65 Captain]

Since the Downforce scoop has a relatively air tight seal to the stock airbox, it can potentially have a ram-air effect and increase power at speed.


0.02

Not even at Veyron speeds. :tongue:

"test NACA did in 1948 provided both the math and the test results to show that the Ram Air effect is nearly useless below about 320 mph. It seems that Ram Air is a dynamic function that is proportional to the square of the air velocity. As such, at 75 mph the gain in air density is about 7/10ths of one percent, or .007 percent. At sea level you'll be getting 14.8 PSI instead of the standard 14.7 PSI. But that's in a perfect world. Ram Air is generally considered to be only about 75% efficient, so in truth at 75mph you are gaining only about 1/2 of one percent. This begins to ramp up as you get faster. At 150 mph the density increase is 2.75% (2.06% adjusted) which is probably helpful in some way but is still in the "nearly impossible to measure" category. At 350 mph the increase in density is in the 15% range and this is where Ram Air becomes usable."

 

[LMR]

Below are 2 emails from one of my brothers who was a mechanic for many years and raced competitively for nearly 30. The first was after he read all the posts about water getting on the filter and second was after I asked him a question about the HKS setup that was on my car from the PO and to compare it to the OEM air box as well as the new setup I have now.


The first one.
I saw the pics & it really is a good looking system. From the pics, I can see the way the filter is positioned (pointing downward). That is actually good because unless the filter is actually flooded (broken levy) water would probably never enter as a liquid. A little water with a lot of air would most likely turn the water to vapor. If a little water did enter as a liquid it would fall to the bottom of the filter (heavier than air) & stay there until it evaporates (vaporizes). A small amount of water vapor entering the engine is not a problem. What do these guys think happens on a humid day? In the days before electronic engine control there was a device called water injection. It sprayed a water mist into the carburetor to cool the air/fuel mixture to stop pinging.

The one guy is right about using a screen. A fine-mesh screen will stop water but not significantly reduce airflow as the side vent is large enough as compared to the intake tube size. If the screen is completely covered with water & the airflow draws it in, it will enter as water droplets & will not harm the engine. Besides, the droplets will probably vaporize by the time they reach the engine (it is a long intake tube). Remember the muscle cars of the 60s & 70s that had functional hood scoops? They used screens for that exact reason. A hood scoop would get more water than your side scoop, don't you think?

Anyway, just being out there & having no problems over time will be the best selling point. If these guys can't recognize a good product, it is their loss.


The second one.
It really comes down to air temp vs. intake restriction. A long tube especially with bends will create some restriction to the airflow. So will the filter. Taking the air from the engine compartment obviously causes higher temps. Its a trade-off. Which method wins? I would say, it depends. The tube design is very important for CAI systems. Proper sizing & minimum bends are critical. Some cars are better suited than others, depending on the intake location & where cold air is available. A bad design can easily nullify any gain from cold air. The normal underhood temp. is also a factor. Most rear & mid engine cars suffer from higher underhood temps. than front engine cars because the front engine cars have cold air from the grille to help cool the engine compartment. Its still hot but not as hot, making CAIs helpful,but less so on front engine cars.

Both air restriction & temp. are somewhat less critical on supercharged engines. Superchargers make their own vacuum so intake restriction can be overcome. Still, less is better, of course. Inlet temp. is probably more important because compressed air entering the cylinders will by nature be hotter than uncompressed air. Still, supercharging can overcome much of this condition simply because it supplies more total air, therefore more power even with the hotter air. Of course, the colder the inlet temp., the more power. There is a reason that one of the parameters used by the ECM to determine fuel amounts is inlet air temp. Colder, denser air will burn more fuel making more power.

In your case the HKS setup was less restrictive & probably had a more efficient filter but took in hot air. The stock setup got colder air but was probably more restrictive(than the HKS). Because you have the supercharger, I would guess that the stock setup would be better. Either way, the new system would beat them both.

Well that was a long answer!

Gotta go,
Ken

I hope this info from my brother will help some of you to decide if my new setup will be a good fit for you too:smile:

He will be seeing it in person soon and going for drive so there may be more input from him that I will post.

Les

 

[Hapa88]

Good summary Les.
I've had experience with a number of different intakes from a wide range of cars. The position of yours will lend itself to a lot of dirt coming into the front part (the rear of the filter will remain relatively clean). Over time the front will become black and will trap large particles in the folds of the filter. The screen covering will help prevent the large particles from getting trapped and thus make it easier to clean later.

You could put the screen on the backside of the vent too, but then the big particles will be trapped there where they're more visible. . It's totally up to you.

In Southern California you don't have to worry too much about the water issue. It doesn't rain that much and the intake is too high to ever suck up enough water to cause engine damage (The water level would have to be past your door - see the NSX Submarine video on YouTube ). The filter should be serviceable and cleanable so there isn't much to worry about if it does get dirty. It's also in a pretty good location where you can see how dirty it's getting fairly easily. Lastly, there should be nothing to worry about in terms of tires kicking up dirt into the filter because of the wheel well liner protecting it (unless you completely removed yours, which I hope you didn't :smile

For light water, K&N style filters are pretty good because they have an oil based coating which repells water to an extent (not sure if this filter is a "dry" one or a "wet" oil based one though).

Overall I think you made a good decision. Product looks very high quality, the only thing I would do is put a screen on that filter, and that's mainly to make it easier to clean later down the road.

 

[stuntman]

Again I see this true for a Naturally Aspirated motor. But again, as i stated before, LMR's car is SUPERCHARGED, so comparing airflow for a system with a pressure gradient of a N/A motor to one that is Supercharged is difficult to do here.

The supercharged motor has a ~6psi difference between the atmospheric pressure and what's going into the motor. If you believe that the throttle body is the bottleneck in the system and thus the restriction of power gains, how does the Supercharger generate an additional 6psi (or more) of pressure within the motor? It does so by pulling additional air in via a belt driven fan (so to speak). The air comes from the same place the N/A motor is getting it from (through the airbox/filter or intake).

Secondly, you're also forgetting the restriction level of the filter element and the surface area of the filter. If you take two identical systems, both with the same tubing size and one has a filter on it, and one does not. Which will flow better? The bottleneck therefore becomes the filter, not the tubing size. Getting bigger piping, a larger filter surface area, and a freer flowing filter is used to counter this inherent reduction in airflow so that the restriction is now more on the throttle body and not the intake system.

It’s all about CFMs. Increasing the CFM of a system increases power, whether that’s done through porting the heads, cams, increasing the size of the throttlebody or intake tubing, OR forced induction, more CFMs = more power.

Air Flow (CFM) = Velocity x Duct Cross Sectional Area

Pressure = Velocity^2

The bottleneck in any system will be the restriction/limitation on power. Racing sanctioning bodies use “restrictor plates” to restrict the cross sectional area and thus CFMs going to the motor thus restricting the power levels. Regardless of air filter size or air inlet piping, the restrictor plate dictates the power level. NASCAR does this (NA) and ALMS uses this for all cars including turbocharged cars (but they also monitor boost pressure and make sure that it is constant because despite a restrictor, more boost pressure given a constant restrictor size = higher velocity and thus more power… to an extent).

In regards to FI compared to NA: FI compresses air and increases CFMs going to the cylinders to increase power. Given the same throttle body, it is able to make more power than NA by increasing the VELOCITY (sucking) through the TB. Now entering a variable into the system like increasing the boost pressure will increase velocity = increased CFM = increased power (while everything from throttle body, restrictor plate, air filter, etc... remain constant).

In either a FI or NA application; if the throttle body is the restriction in the system, then any changes to the air intake system will make minimal to no effect on CFMs or power. Similarly if the airbox and or the intake manifold is the restriction of the system, then increasing the size of the throttle body will have no power gains.

Lastly, the Ram-Air effect, though could work on a N/A system, is practically gone with a forced induction system. Any additional "ram-air" flow is negated by the turbulence created by the turbo or supercharger rotor/screws.

Not even at Veyron speeds. :tongue:

"test NACA did in 1948 provided both the math and the test results to show that the Ram Air effect is nearly useless below about 320 mph. It seems that Ram Air is a dynamic function that is proportional to the square of the air velocity. As such, at 75 mph the gain in air density is about 7/10ths of one percent, or .007 percent. At sea level you'll be getting 14.8 PSI instead of the standard 14.7 PSI. But that's in a perfect world. Ram Air is generally considered to be only about 75% efficient, so in truth at 75mph you are gaining only about 1/2 of one percent. This begins to ramp up as you get faster. At 150 mph the density increase is 2.75% (2.06% adjusted) which is probably helpful in some way but is still in the "nearly impossible to measure" category. At 350 mph the increase in density is in the 15% range and this is where Ram Air becomes usable."

Its all about pressure differentials. Drawing air from a low pressure area behind the front bumper will result in a quantifiable power loss while any increasing the pressure in the airbox will result in power gains.

There is a reason that NASCAR, some GT cars, Drag racing cars use a cowl-intake designs – taking air from the high pressure area at the base of the windshield and (while minute) seeing power gains from it. Profesional race teams go to great lengths to increase the pressure in the airbox to increase the velocity going through their static restriction to make more power. While a properly designed system probably wont net 1hp or so below 50mph, Pressure = Velocity^2 so as speeds increase, pressure greatly increases.

When you're fighting for thousandths of a second, these measures do matter and make a difference. Not so much for a street car where you're looking to *feel* an improvement. In that case you need to find a much more substantial gain in CFMs.


Billy

 

[Hapa88]

It’s all about CFMs. Increasing the CFM of a system increases power, whether that’s done through porting the heads, cams, increasing the size of the throttlebody or intake tubing, OR forced induction, more CFMs = more power.

Air Flow (CFM) = Velocity x Duct Cross Sectional Area

Pressure = Velocity^2

The bottleneck in any system will be the restriction/limitation on power. Racing sanctioning bodies use “restrictor plates” to restrict the cross sectional area and thus CFMs going to the motor thus restricting the power levels. Regardless of air filter size or air inlet piping, the restrictor plate dictates the power level. NASCAR does this (NA) and ALMS uses this for all cars including turbocharged cars (but they also monitor boost pressure and make sure that it is constant because despite a restrictor, more boost pressure given a constant restrictor size = higher velocity and thus more power… to an extent).

In regards to FI compared to NA: FI compresses air and increases CFMs going to the cylinders to increase power. Given the same throttle body, it is able to make more power than NA by increasing the VELOCITY (sucking) through the TB. Now entering a variable into the system like increasing the boost pressure will increase velocity = increased CFM = increased power (while everything from throttle body, restrictor plate, air filter, etc... remain constant).

In either a FI or NA application; if the throttle body is the restriction in the system, then any changes to the air intake system will make minimal to no effect on CFMs or power. Similarly if the airbox and or the intake manifold is the restriction of the system, then increasing the size of the throttle body will have no power gains.




Its all about pressure differentials. Drawing air from a low pressure area behind the front bumper will result in a quantifiable power loss while any increasing the pressure in the airbox will result in power gains.

There is a reason that NASCAR, some GT cars, Drag racing cars use a cowl-intake designs – taking air from the high pressure area at the base of the windshield and (while minute) seeing power gains from it. Profesional race teams go to great lengths to increase the pressure in the airbox to increase the velocity going through their static restriction to make more power. While a properly designed system probably wont net 1hp or so below 50mph, Pressure = Velocity^2 so as speeds increase, pressure greatly increases.

When you're fighting for thousandths of a second, these measures do matter and make a difference. Not so much for a street car where you're looking to *feel* an improvement. In that case you need to find a much more substantial gain in CFMs.


Billy

Billy,
I think we are on the same page. What needs to be determined here is where the restriction takes place for a FI system like what LMR is running. The increased CFMs generated by the supercharger weren't taken into consideration when Honda designed and developed the OEM intake box.

In order to determine where the restriction lies, we need to know is what is the max CFM of the factory NSX airbox, the max CFM of the factory NSX throttle body, and the max CFM of this new intake system.

 

[stuntman]

Billy,
I think we are on the same page. What needs to be determined here is where the restriction takes place for a FI system like what LMR is running. The increased CFMs generated by the supercharger weren't taken into consideration when Honda designed and developed the OEM intake box.

In order to determine where the restriction lies, we need to know is what is the max CFM of the factory NSX airbox, the max CFM of the factory NSX throttle body, and the max CFM of this new intake system.

Agreed. Until the CFM is measured on the factory airbox and the new intake system, everything will be speculation

 

[PKim]

Too bad you didn't do a pre and post dyno. That should of given some scientific evidence to whether this CAI is beneficial. But then you might not care since you love the sound....!:smile:
I also agree with some ppl that think the OEM intake is hard to beat. I currently have the downforce intake scoop with unifilter and the thing I like about it is that it is easy to clean the filter. This CAI filter is located way down by the side scoop and it seem like cleaning and changing it out is going to be a PITA ( removing rear wheel, taking the liner out...)

 

[LMR]

Too bad you didn't do a pre and post dyno. That should of given some scientific evidence to whether this CAI is beneficial. But then you might not care since you love the sound....!:smile:
I also agree with some ppl that think the OEM intake is hard to beat. I currently have the downforce intake scoop with unifilter and the thing I like about it is that it is easy to clean the filter. This CAI filter is located way down by the side scoop and it seem like cleaning and changing it out is going to be a PITA ( removing rear wheel, taking the liner out...)

I have a pre dyno and plan on having a post dyno soon.

I'm not worried about cleaning as it probably will not need to be cleaned until after 15k to 20k per Giancarlo at B-Line. Removing the wheel and liner is about a 15 minute job not much of a PITA IMO.

 

[stuntman]

I have a pre dyno and plan on having a post dyno soon.

I'm not worried about cleaning as it probably will not need to be cleaned until after 15k to 20k per Giancarlo at B-Line. Removing the wheel and liner is about a 15 minute job not much of a PITA IMO.

Dyno testing really needs to be done back-to-back with multiple runs on each configuration taking the average # of each setup (on the same day and as soon as possible between changes). Just dynoing one setup once then the other leaves too many variables, especially when you test in different times/temperatures during the day or even worse - on differing days.

Heck, oil temperature from a cold motor relative to a fully warmed motor can easily vary 10whp+, let alone 2-3hp variances or more with most things constant.


0.02

 

[LMR]

Good summary Les.
I've had experience with a number of different intakes from a wide range of cars. The position of yours will lend itself to a lot of dirt coming into the front part (the rear of the filter will remain relatively clean). Over time the front will become black and will trap large particles in the folds of the filter. The screen covering will help prevent the large particles from getting trapped and thus make it easier to clean later.

You could put the screen on the backside of the vent too, but then the big particles will be trapped there where they're more visible. . It's totally up to you.

In Southern California you don't have to worry too much about the water issue. It doesn't rain that much and the intake is too high to ever suck up enough water to cause engine damage (The water level would have to be past your door - see the NSX Submarine video on YouTube ). The filter should be serviceable and cleanable so there isn't much to worry about if it does get dirty. It's also in a pretty good location where you can see how dirty it's getting fairly easily. Lastly, there should be nothing to worry about in terms of tires kicking up dirt into the filter because of the wheel well liner protecting it (unless you completely removed yours, which I hope you didn't :smile

For light water, K&N style filters are pretty good because they have an oil based coating which repells water to an extent (not sure if this filter is a "dry" one or a "wet" oil based one though).

Overall I think you made a good decision. Product looks very high quality, the only thing I would do is put a screen on that filter, and that's mainly to make it easier to clean later down the road.

Adrian,

Thanks for your input as I respect your posts and insights on this site:smile:. That goes for Billy too as his background and experience speak for themselves.

As for the summary the credit goes to my brother as I was just copying and pasting from an email from him. His background and experience also speak for themselves.

As for the cover I thought about it as I have one on my 4Runner that has the K&N intake kit for a few resaons. Since it is a 4X4 and I do take offroad a lot I put it on to keep it dry when going through water and to minimize the dust build up so I only have to clean it after every 2 or 3 times I take it out instead of everytime. The last reason was to restrict some of the air flow because it was causing the check engine light to come on due to too much air. I do not want to restrict any air flow on my NSX so I will wait to see how offen I need to clean it and then decide if it is needed.

Also all this talk about the OEM airbox does not apply to my car for all these comparisons as to how much HP increase there my be from the old setup to the new as if you all remember on my first post my car had the HKS intake setup not the OEM. I only mentioned the OEM setup because of something CL65 said and wanted my brothers input on it. But it's all good as this my help other people who have the OEM setup and may want to go the B-Line setup.

Just received another email from my brother and will read it so there maybe another post soon:smile:

 

[lowellhigh79]

A simple funnel with a wide enough opening on one end (to seal up against the outlet of whatever setup at the point where it attaches to the TB) ), a vacuum gauge McGyvered onto the other end of the funnel and a home vacuum applied to the end where the gauge is at is all you need to test each setup's restrictions. Whichever setup creates the most vacuum at the gauge has the most restriction.

Regards,

Danny

 

[LMR]

Finally got around to having the after installation dyno done. Here are the before and after results.

 

[Ko-nsx]

Cool, wish the intake fit my widebody.:frown: