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Got mine 2 weeks ago from infiniti dealer for 425$. They had 2 in stock at the time. Possibly was the only 2 left in the nation until ams next batch.

Do I feel it made a difference? Not really. I did replace my old super dirty stock filters with brand new ones 5 days before installing for a more accurate comparison.
Do I regret it? Not at all.
Would I buy it again? Of course.
Why would you buy it again? Because it's cool to say that you have it?
 
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Why would you buy it again? Because it's cool to say that you have it?
Mostly because I have an addiction.

In theory a properly sized cone filter should have much larger surface area and be more free flowing and thus less restrictive/allow more air flow. Whether or not that extra airflow can be utilized, or at what point in modding it would be beneficial is another question.

also what i can “feel” vs what is reality is often 2 different things. My butt dyno doesn’t pick up on gains very easily i need something substantial to notice a difference. Personally I think it is almost impossible to tell any difference by “feeling” in acceleration at or below .3sec faster from say 40-80mph. Especially since .3sec is pretty standard deviation from one pull/run to another with zero changes in-between. But if doing a proper comparison it could still be say .2sec faster on avg over 10runs with stock vs a mod like CAI and thus be beneficial even if you can't “feel” it. I have not done this testing though to be certain of anything.

in conclusion i like to think and tell myself it made a difference mostly to feed my addiction.
 

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So the CAI made no difference yet you'd spend the money on it again? To each their own, I guess.
Short answer. Yes
Long answer. See previous post.

I think the theory and idea behind it is sound enough to possibly serve a purpose or have a benefit. Especially with my future goals and plans in mind even if it has little to no benefit for me currently at this time.
 

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Mostly because I have an addiction.

In theory a properly sized cone filter should have much larger surface area and be more free flowing and thus less restrictive/allow more air flow. Whether or not that extra airflow can be utilized, or at what point in modding it would be beneficial is another question.

also what i can “feel” vs what is reality is often 2 different things. My butt dyno doesn’t pick up on gains very easily i need something substantial to notice a difference. Personally I think it is almost impossible to tell any difference by “feeling” in acceleration at or below .3sec faster from say 40-80mph. Especially since .3sec is pretty standard deviation from one pull/run to another with zero changes in-between. But if doing a proper comparison it could still be say .2sec faster on avg over 10runs with stock vs a mod like CAI and thus be beneficial even if you can't “feel” it. I have not done this testing though to be certain of anything.

in conclusion i like to think and tell myself it made a difference mostly to feed my addiction.
Sounds like an AA meeting:

"My name is 17awdQ50P and I'm an addict".

"Welcome to the forum 17awdQ50P!"

I would think the meager impact of a CAI during multiple runs would be lost in the other variables that affect performance from run to run, especially on a otherwise stock car as the OP indicated he isn't going to tune.
 

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What I am trying to understand is if the standard setup has a problem meeting the maximum flow demands of the engine. With each intake feeding only three cylinders I am skeptical that it would have a problem keeping up. Has anyone put a manifold pressure (or vacuum) gage just downstream of the air filter to check?
 

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What I am trying to understand is if the standard setup has a problem meeting the maximum flow demands of the engine. With each intake feeding only three cylinders I am skeptical that it would have a problem keeping up. Has anyone put a manifold pressure (or vacuum) gage just downstream of the air filter to check?
I highly doubt in stock form it is a restriction and just a drop in hi flow filter would probably raise that ceiling up to not be a restriction for a few basic bolt ons and a JB4. Now full catless, E85, custom tune. I could see the cone filter having benefits.
 

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2017 Q50 Red Sport 400 RWD
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That's one of those feel good mods as well.

I am not totally convinced of this. Perhaps smooth is not always better than corrugated. But I wouldn't be surprised if there were some gains by switching to smooth intake tubing.

-------------------------

Explanation of the empirical results may be explained in the following manner:
Head Loss in a Pipe
Overall head loss in a pipe is affected by a number of factors which include the viscosity of the fluid, the size of the internal pipe diameter, the internal roughness of the inner surface of the pipe, the change in elevation between the ends of the pipe and the length of the pipe along which the fluid travels.
Valves and fittings on a pipe also contribute to the overall head loss that occurs, however these must be calculated separately to the pipe wall friction loss, using a method of modeling pipe fitting losses with k factors.
Darcy Weisbach Formula
The Darcy formula or the Darcy-Weisbach equation as it tends to be referred to, is now accepted as the most accurate pipe friction loss formula, and although more difficult to calculate and use than other friction loss formula, with the introduction of computers, it has now become the standard equation for hydraulic engineers.
Weisbach first proposed the relationship that we now know as the Darcy-Weisbach equation for calculating friction loss in a pipe.
Darcy-Weisbach equation:

hf = f (L/D) x (v^2/2g)

where:
hf = head loss (m)
f = friction factor
L = length of pipe work (m)
d = inner diameter of pipe work (m)
v = velocity of fluid (m/s)
g = acceleration due to gravity (m/s²)

or:

hf = head loss (ft)
f = friction factor
L = length of pipe work (ft)
d = inner diameter of pipe work (ft)
v = velocity of fluid (ft/s)
g = acceleration due to gravity (ft/s²)
The establishment of the friction factors was however still unresolved, and indeed was an issue that needed further work to develop a solution such as that produced by the Colebrook-White formula and the data presented in the Moody chart.
The Moody Chart
The Moody Chart finally provided a method of finding an accurate friction factor and this encouraged use of the Darcy-Weisbach equation, which quickly became the method of choice for hydraulic engineers.
Friction Factor Chart / Moody Chart
The friction factor or Moody chart is the plot of the relative roughness (e/D) of a pipe against the Reynold's number. The blue lines plot the friction factor for flow in the wholly turbulent region of the chart, while the straight black line plots the friction factor for flow in the wholly laminar region of the chart.
friction_factor_chart_1.gif
In 1944, LF Moody plotted the data from the Colebrook equation and the resulting chart became known as The Moody Chart or sometimes the Friction Factor Chart. It was this chart which first enabled the user to obtain a reasonably accurate friction factor for turbulent flow conditions, based on the Reynolds number and the Relative Roughness of the pipe.
Friction Factor for Laminar Flow
The friction factor for laminar flow is calculated by dividing 64 by the Reynold's number.
Friction factor (for laminar flow) = 64 / Re

MANNING'S ROUGHNESS COEFFICIENT

Manning's Formula for Gravity Flow

Polyethylene PE - Corrugated with corrugated inner walls 0.018 - 0.025
Polyvinyl Chloride PVC - with smooth inner walls 0.009 - 0.011


CONCLUSIONS:

e/D of the corrugated surface > e/D of the smooth surface
Corrugated duct creates larger layer of the turbulent flow close to the wall effectively reducing the laminar (fast) flow cross section area. Any bends make conditions worse.

Therefore, replacing corrugated hoses with smooth bore ducting improves the turbo compressor efficiency.
 

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Any before and after dyno charts to prove the theory..? Butt Dyno not included.

I am not totally convinced of this. Perhaps smooth is not always better than corrugated. But I wouldn't be surprised if there were some gains by switching to smooth intake tubing.

-------------------------

Explanation of the empirical results may be explained in the following manner:
Head Loss in a Pipe
Overall head loss in a pipe is affected by a number of factors which include the viscosity of the fluid, the size of the internal pipe diameter, the internal roughness of the inner surface of the pipe, the change in elevation between the ends of the pipe and the length of the pipe along which the fluid travels.
Valves and fittings on a pipe also contribute to the overall head loss that occurs, however these must be calculated separately to the pipe wall friction loss, using a method of modeling pipe fitting losses with k factors.
Darcy Weisbach Formula
The Darcy formula or the Darcy-Weisbach equation as it tends to be referred to, is now accepted as the most accurate pipe friction loss formula, and although more difficult to calculate and use than other friction loss formula, with the introduction of computers, it has now become the standard equation for hydraulic engineers.
Weisbach first proposed the relationship that we now know as the Darcy-Weisbach equation for calculating friction loss in a pipe.
Darcy-Weisbach equation:

hf = f (L/D) x (v^2/2g)

where:
hf = head loss (m)
f = friction factor
L = length of pipe work (m)
d = inner diameter of pipe work (m)
v = velocity of fluid (m/s)
g = acceleration due to gravity (m/s²)

or:

hf = head loss (ft)
f = friction factor
L = length of pipe work (ft)
d = inner diameter of pipe work (ft)
v = velocity of fluid (ft/s)
g = acceleration due to gravity (ft/s²)
The establishment of the friction factors was however still unresolved, and indeed was an issue that needed further work to develop a solution such as that produced by the Colebrook-White formula and the data presented in the Moody chart.
The Moody Chart
The Moody Chart finally provided a method of finding an accurate friction factor and this encouraged use of the Darcy-Weisbach equation, which quickly became the method of choice for hydraulic engineers.
Friction Factor Chart / Moody Chart
The friction factor or Moody chart is the plot of the relative roughness (e/D) of a pipe against the Reynold's number. The blue lines plot the friction factor for flow in the wholly turbulent region of the chart, while the straight black line plots the friction factor for flow in the wholly laminar region of the chart.
friction_factor_chart_1.gif
In 1944, LF Moody plotted the data from the Colebrook equation and the resulting chart became known as The Moody Chart or sometimes the Friction Factor Chart. It was this chart which first enabled the user to obtain a reasonably accurate friction factor for turbulent flow conditions, based on the Reynolds number and the Relative Roughness of the pipe.
Friction Factor for Laminar Flow
The friction factor for laminar flow is calculated by dividing 64 by the Reynold's number.
Friction factor (for laminar flow) = 64 / Re

MANNING'S ROUGHNESS COEFFICIENT

Manning's Formula for Gravity Flow

Polyethylene PE - Corrugated with corrugated inner walls 0.018 - 0.025
Polyvinyl Chloride PVC - with smooth inner walls 0.009 - 0.011


CONCLUSIONS:

e/D of the corrugated surface > e/D of the smooth surface
Corrugated duct creates larger layer of the turbulent flow close to the wall effectively reducing the laminar (fast) flow cross section area. Any bends make conditions worse.

Therefore, replacing corrugated hoses with smooth bore ducting improves the turbo compressor efficiency.
 

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18 RS Q50 RWD
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I am not totally convinced of this. Perhaps smooth is not always better than corrugated. But I wouldn't be surprised if there were some gains by switching to smooth intake tubing.

-------------------------

Explanation of the empirical results may be explained in the following manner:
Head Loss in a Pipe
Overall head loss in a pipe is affected by a number of factors which include the viscosity of the fluid, the size of the internal pipe diameter, the internal roughness of the inner surface of the pipe, the change in elevation between the ends of the pipe and the length of the pipe along which the fluid travels.
Valves and fittings on a pipe also contribute to the overall head loss that occurs, however these must be calculated separately to the pipe wall friction loss, using a method of modeling pipe fitting losses with k factors.
Darcy Weisbach Formula
The Darcy formula or the Darcy-Weisbach equation as it tends to be referred to, is now accepted as the most accurate pipe friction loss formula, and although more difficult to calculate and use than other friction loss formula, with the introduction of computers, it has now become the standard equation for hydraulic engineers.
Weisbach first proposed the relationship that we now know as the Darcy-Weisbach equation for calculating friction loss in a pipe.
Darcy-Weisbach equation:

hf = f (L/D) x (v^2/2g)

where:
hf = head loss (m)
f = friction factor
L = length of pipe work (m)
d = inner diameter of pipe work (m)
v = velocity of fluid (m/s)
g = acceleration due to gravity (m/s²)

or:

hf = head loss (ft)
f = friction factor
L = length of pipe work (ft)
d = inner diameter of pipe work (ft)
v = velocity of fluid (ft/s)
g = acceleration due to gravity (ft/s²)
The establishment of the friction factors was however still unresolved, and indeed was an issue that needed further work to develop a solution such as that produced by the Colebrook-White formula and the data presented in the Moody chart.
The Moody Chart
The Moody Chart finally provided a method of finding an accurate friction factor and this encouraged use of the Darcy-Weisbach equation, which quickly became the method of choice for hydraulic engineers.
Friction Factor Chart / Moody Chart
The friction factor or Moody chart is the plot of the relative roughness (e/D) of a pipe against the Reynold's number. The blue lines plot the friction factor for flow in the wholly turbulent region of the chart, while the straight black line plots the friction factor for flow in the wholly laminar region of the chart.
friction_factor_chart_1.gif
In 1944, LF Moody plotted the data from the Colebrook equation and the resulting chart became known as The Moody Chart or sometimes the Friction Factor Chart. It was this chart which first enabled the user to obtain a reasonably accurate friction factor for turbulent flow conditions, based on the Reynolds number and the Relative Roughness of the pipe.
Friction Factor for Laminar Flow
The friction factor for laminar flow is calculated by dividing 64 by the Reynold's number.
Friction factor (for laminar flow) = 64 / Re

MANNING'S ROUGHNESS COEFFICIENT

Manning's Formula for Gravity Flow

Polyethylene PE - Corrugated with corrugated inner walls 0.018 - 0.025
Polyvinyl Chloride PVC - with smooth inner walls 0.009 - 0.011


CONCLUSIONS:

e/D of the corrugated surface > e/D of the smooth surface
Corrugated duct creates larger layer of the turbulent flow close to the wall effectively reducing the laminar (fast) flow cross section area. Any bends make conditions worse.

Therefore, replacing corrugated hoses with smooth bore ducting improves the turbo compressor efficiency.
undoubtably the nissan engineers (are you one?) were well aware of all this but the sound reduction was the priority.
 

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Damn...Fluid flow equations, Fanning friction factors and Reynolds numbers. Reminds me of my mass transfer class in engineering.

I stated the same conclusion in an earlier thread about this. Smooth bore > rough bore.
 

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2017 Q50 Red Sport 400 RWD
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Any before and after dyno charts to prove the theory..? Butt Dyno not included.
Not on this car but I believe it was well documented, with dynos, on the 4th gen Trans Am (Ram Air) where guys would switch a short corrugated tube b/t the air box and throttle body with a smooth tube. I'm sure some cars benefit more than others. Maybe some not at all. But, let's put it this way, it can't hurt, right?
 

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2017 Q50 Red Sport 400 RWD
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undoubtably the nissan engineers (are you one?) were well aware of all this but the sound reduction was the priority.
Civil, not mechanical, engineer here. ;)
 
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Civil, not mechanical, engineer here. ;)
You know what we called civil engineers at college? Turd engineers. All they need to know is that sh1t flows downhill and they're good to go. :ROFLMAO:
 
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Not on this car but I believe it was well documented, with dynos, on the 4th gen Trans Am (Ram Air) where guys would switch a short corrugated tube b/t the air box and throttle body with a smooth tube. I'm sure some cars benefit more than others. Maybe some not at all. But, let's put it this way, it can't hurt, right?
I made up a smooth bend and tube intake setup on my '18 RAM to replace the ribbed OE one so I agree that it can't hurt.
 

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95844
 
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But did it make a perceptible difference?
 

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But did it make a perceptible difference?
Butt dyno seemed to pick up a minute bit better throttle response. Placebo effect probably.
 

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2017 Q50 Red Sport 400 RWD
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You know what we called civil engineers at college? Turd engineers. All they need to know is that sh1t flows downhill and they're good to go. :ROFLMAO:
I don't have anything to do with sewage. Storm drains, drainage channels, grading, roadway improvements, bridges, ADA compliance, pedestrian sidewalks and trails, utility relocations/coordination, storm water treatment, medians, traffic signals, signing, striping, traffic control, etc.
 

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I don't have anything to do with sewage. Storm drains, drainage channels, grading, roadway improvements, bridges, ADA compliance, pedestrian sidewalks and trails, utility relocations/coordination, storm water treatment, medians, traffic signals, signing, striping, traffic control, etc.
I'm just yanking your chain. Check your conversations.
 

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