[Sonny Burnett]

The guys at Mighty Car Mods probably messed up the air flow by using corrugated tubing.

Most likely not, ambient weather and elevation are going to play a bigger role on the inlet side rather than if a stock airbox or a CAI is in place unless you're running an open turbo drag car lol. This is why during the summer months, the old VW GTi's and Jetta's with 1.8T's were annoying to drive the stock intercoolers heatsoaked pretty bad. I will say, I more than likely would personally buy the V1 if I were to buy into the upgrade being offered which frees up the kinks, but not at the current asking price.

 

[Greg]

The mighty car mods test is hugely flawed.

First of all the title is "cold air intakes mythbusted" Yet the only cold air intake in the entire video is the STOCK intake, and the stock cold air intake on the Nissan Skyline is quite good. This video never compared the stock intake against an aftermarket cold air intake. It simply compares the stock well designed intake to the stock intake with some very poorly executed filter mods.

The first "intake" they compare to is a HOT AIR INTAKE. Calling it a "cold air intake" is misleading at best. They made it my simply connecting a cone filter to the stock intake thereby sucking in hot air.

The second intake was the same hot air intake but with the headlight removed. The filter still isn't sealed to the outside air, so it's certainly not a cold air intake, it may be a warm air intake at best.

The third is just a joke. Obviously nobody would run an intake like that. Yes, this one is cold air, but the extra 6 feet of corrugated tubing are going to seriously interfere with flow. Amzingly this one did show a 4+hp gain even with all that tubing. That actually shows how well the filter flows vs. the stock filter.

Bottom line, these guys never tested an aftermarket intake, let alone and aftermarket cold air intake, so they didn't even try to mythbust what they said they would. Instead they tested various filter mods on the stock intake. I also want to mention that they are sponsored by an auto insurance company, not exactly a mod friendly organization.

Greg

 

[Greg]

Exactly, at the throttle body, not at the inlet of the turbo.....Which the video more or less shows. This is why we have intercoolers.

We have intercoolers to cool the air after the turbo. The temperature of the air going IN to the intercooler has a direct effect on the temperature of the air going out. Colder air in equals colder air out. We made a chart from our air temperature logs. These are the temperatures of the air in the intake manifold at full boost with various intakes.

Greg

 

[Greg]

Most likely not, ambient weather and elevation are going to play a bigger role on the inlet side rather than if a stock airbox or a CAI is in place unless you're running an open turbo drag car lol.

YES! Weather does play a very large roll in performance. On a day at sea level with a pressure of 30.75 and a temperature of 35F, you will have more power than at 1000' 29.10 and 105F. In fact in that case, I would agree that the difference will be greater than the increase from most aftermarket products. However in either case a stock car will have less than a car with a good intake. Since none of my competitor's are selling a weather conditions package, all cars must race head to head in the same weather. By lowering temperature and increasing pressure a good intake gives an advantage.

This is why during the summer months, the old VW GTi's and Jetta's with 1.8T's were annoying to drive the stock intercoolers heatsoaked pretty bad.

Sonny, we are in agreement here. Heat is bad, it hurts performance, especially in turbo cars. Thus reducing heat is good

I will say, I more than likely would personally buy the V1 if I were to buy into the upgrade being offered which frees up the kinks, but not at the current asking price.

What product would you like to see? You seem like an enthusiast, and a thinking person, so I would really like to know. We plan on having a very complete underhood product line for this car.

Greg

 

[TomM]

To keep it simple, intake temperatures do matter. The object of turbocharging is to cram more fuel and oxygen into the combustion chamber, resulting in more power per stroke. It is fact that cooler air has more oxygen molecules per cubic inch than warmer air. It is that simple.

Given that the turbo has an intercooler and a waste gate, I'm wondering if it actually does matter.

In most cases, the turbo has plenty of spin to get the air to the proper pressure and temperature. Higher inlet temperature means it has to pump in a bit more air, but it should have the headroom to do that. Whenever the waste gate is open, I wouldn't think the inlet temperature is going to make any significant difference.

I guess at lower RPM where the turbo is still spinning up, a lower inlet T could help a bit, but I doubt anyone could actually tell the difference.

Maybe I'm missing something about the way turbos operate. Inlet temperature would seem to be more of an issue for a NA engine than a turbo.

 

[PureAdrenaline]

Given that the turbo has an intercooler and a waste gate, I'm wondering if it actually does matter.

In most cases, the turbo has plenty of spin to get the air to the proper pressure and temperature. Higher inlet temperature means it has to pump in a bit more air, but it should have the headroom to do that. Whenever the waste gate is open, I wouldn't think the inlet temperature is going to make any significant difference.

I guess at lower RPM where the turbo is still spinning up, a lower inlet T could help a bit, but I doubt anyone could actually tell the difference.

Maybe I'm missing something about the way turbos operate. Inlet temperature would seem to be more of an issue for a NA engine than a turbo.

Lets step back a bit. Tell me this...why would any manufacturer of a turbo/supercharged car go to the trouble to duct cooler outside air into it intake. And they all do. They spend time and money to design an intake that brings in fresh air from the outside. I am saying if it did not make a difference i seriously doubt they would spend the money to do it. They would just suck it right out of the engine compartment. Just another way to look at it.

 

[Greg]

Given that the turbo has an intercooler and a waste gate, I'm wondering if it actually does matter.

Yes it does matter, that's why every single manufacturer ducts cold air to the turbo in production cars. That's why Fiat did it in this car, and it's why the Factory Abarth team did it with the 296hp factory Rally 124.

In most cases, the turbo has plenty of spin to get the air to the proper pressure and temperature. Higher inlet temperature means it has to pump in a bit more air, but it should have the headroom to do that.

It can spin faster to get it to the proper pressure, but that makes the air even hotter. Take a look at a turbo compressor map, almost anytime you spin it faster for a given amount of boost the discharge temps go up.

I guess at lower RPM where the turbo is still spinning up, a lower inlet T could help a bit, but I doubt anyone could actually tell the difference.

It's not just the temperature improvement, it's the improved flow and pressure differences. These factors add up.

Maybe I'm missing something about the way turbos operate. Inlet temperature would seem to be more of an issue for a NA engine than a turbo.

It's actually a much bigger factor in a turbo engine. That's why there are such huge efforts to lower temps in a turbo engine with intakes, intercoolers, water injection, Cryogenic sprays and more.

Take a look at the chart I just posted, those temps are not at the turbo inlet, they are at the manifold which shows that the intakes lower temperatures. You can also find the pressure charts on our website.

Greg

 

[Greg]

Lets step back a bit. Tell me this...why would any manufacturer of a turbo/supercharged car go to the trouble to duct cooler outside air into it intake. And they all do. They spend time and money to design an intake that brings in fresh air from the outside. I am saying if it did not make a difference i seriously doubt they would spend the money to do it. They would just suck it right out of the engine compartment. Just another way to look at it.

THIS!

Greg

 

[TomM]

I guess my point is that the temperature coming out of the intercooler is what matters most, moreso than the temperature going into the turbo. You certainly need cool outside air for that.

Doing a few calculations, assuming the turbo is keeping a constant pressure of +4 psi over ambient, if the intercooler outlet is 40°C (104°F) the air will have a density of 1.43 g/L. If that can be brought down to 30°C (86°F), it will have a density of 1.48 g/L. So dropping the intercooler temp by nearly 20°F will get you 3% higher density. A lower temperature drop gets you proportionately less.

3% isn't nothing, of course, but is still not huge. If you're in a situation where every little bit matters, then of course it makes a difference but under most circumstances people would be hard-pressed to notice it.

 

[JFernald]

Exactly, at the throttle body, not at the inlet of the turbo.....Which the video more or less shows. This is why we have intercoolers.

It actually starts in the atmosphere. Back in the '60s, when I learned to drive, you had to have adjustments made if you were moving from Houston to Denver, due to the change in altitude, and resulting difference in oxygen density. Now cars make automatic adjustments for altitude.

 

[[email protected]]

I guess my point is that the temperature coming out of the intercooler is what matters most, moreso than the temperature going into the turbo. You certainly need cool outside air for that.

What Greg means by air temp in the intake manifold, is the post intercooler air temp (post intercooler, to throttle body, to intake manifold).

Meaning, our temp tests in the charts were done on post intercooler air temps. So the data you are seeing in the charts shows exactly how much each intake affected air temperatures, even after going through the intercooler.

If we showed data measured at the turbo inlet, the differences would be even more significant, but not as indicative of what is actually going back into the intake manifold.

 

[Greg]

I guess my point is that the temperature coming out of the intercooler is what matters most, moreso than the temperature going into the turbo.

YES! And that's why I posted EXACTLY THAT. Those temperatures are lower with our intake.

Doing a few calculations, assuming the turbo is keeping a constant pressure of +4 psi over ambient, if the intercooler outlet is 40°C (104°F) the air will have a density of 1.43 g/L. If that can be brought down to 30°C (86°F), it will have a density of 1.48 g/L. So dropping the intercooler temp by nearly 20°F will get you 3% higher density. A lower temperature drop gets you proportionately less.

3% isn't nothing, of course, but is still not huge. If you're in a situation where every little bit matters, then of course it makes a difference but under most circumstances people would be hard-pressed to notice it.

Very Good. That 3% isn't nothing, but it is worth about 4.8 horsepower due to the density increase alone. Add in the increase from the pressure difference, and the allowable increase in timing from the lower temperature and it adds up. In this specific case it adds up to about 10 horsepower give or take a little depending on which intake we are talking about

Greg

 

[Greg]

Just to clarify, this chart shows air temperatures AFTER the intercooler. Specifically just after the throttle body. They are not the temperatures at the turbo inlet.

Greg

 

[PureAdrenaline]

Just to clarify, this chart shows air temperatures AFTER the intercooler. Specifically just after the throttle body. They are not the temperatures at the turbo inlet.

Greg

The data is exactly what you need to see. Temps after the intercooler going into the intake manifold. Empirical data that shows the functionality of the intakes versus the stock one.

 

[[email protected]]

One thing mentioned was the comparison of price value vs amount of power gained (or more generally whatever gain is to be had), and logically that is a rational way to view pretty much anything you buy.

But one thing that may not be taken into account when doing so is that you are using peak numbers (hp/tq), and this is deceptive. If you look at the powerband on the dyno chart and scan the entire pull throughout the entire rpm range for each intake, you will see what I'm getting at. There are places in the powerband where the intakes make a huge difference in the way the car performs over the stock system, not just at the peak power/torque rpms, but at the lower rpm range as well as the higher rpm range.

For example, the V2 and the V4 both have at least 20 lb/ft of tq over the stock intake in the lower rpm range (specifically 3000rpm). That is a very worthwhile gain, especially so because it is in an area of the powerband that you will most certainly "feel" a difference and be able to put that gain to good use. This is where the differences in flow, temperature, pressure, etc along with how the ECU responds to this new sensor data, while seemingly low in percentage on a lone chart, really makes a significant difference.

 

[[email protected]]

Some more looks at intakes...

 

[JFernald]

One thing mentioned was the comparison of price value vs amount of power gained (or more generally whatever gain is to be had), and logically that is a rational way to view pretty much anything you buy.

But one thing that may not be taken into account when doing so is that you are using peak numbers (hp/tq), and this is deceptive. If you look at the powerband on the dyno chart and scan the entire pull throughout the entire rpm range for each intake, you will see what I'm getting at. There are places in the powerband where the intakes make a huge difference in the way the car performs over the stock system, not just at the peak power/torque rpms, but at the lower rpm range as well as the higher rpm range.

For example, the V2 and the V4 both have at least 20 lb/ft of tq over the stock intake in the lower rpm range (specifically 3000rpm). That is a very worthwhile gain, especially so because it is in an area of the powerband that you will most certainly "feel" a difference and be able to put that gain to good use. This is where the differences in flow, temperature, pressure, etc along with how the ECU responds to this new sensor data, while seemingly low in percentage on a lone chart, really makes a significant difference.

Is that also why the GFB DV+ makes sense? It doesn't add more peak hp/tq, but it makes boost available at lower rpm, right?

 

[AirCavHokie]

One thing mentioned was the comparison of price value vs amount of power gained (or more generally whatever gain is to be had), and logically that is a rational way to view pretty much anything you buy.

But one thing that may not be taken into account when doing so is that you are using peak numbers (hp/tq), and this is deceptive. If you look at the powerband on the dyno chart and scan the entire pull throughout the entire rpm range for each intake, you will see what I'm getting at. There are places in the powerband where the intakes make a huge difference in the way the car performs over the stock system, not just at the peak power/torque rpms, but at the lower rpm range as well as the higher rpm range.

For example, the V2 and the V4 both have at least 20 lb/ft of tq over the stock intake in the lower rpm range (specifically 3000rpm). That is a very worthwhile gain, especially so because it is in an area of the powerband that you will most certainly "feel" a difference and be able to put that gain to good use. This is where the differences in flow, temperature, pressure, etc along with how the ECU responds to this new sensor data, while seemingly low in percentage on a lone chart, really makes a significant difference.

I agree that vendors using peak numbers is deceptive because it does not represent the relative performance of their parts against stock ones across the rpm band. I used the peak values as a simplification because they are the only data point pairs on the dyno charts that do not have to be inferred from the graph. The peaks are conveniently presented and highlighted on the vendor's dyno charts. Comparing the relative areas between stock and aftermarket power curves would be more accurate, but I don't do calculus for fun. Determining the relative value of a 1 ft-lb increase in torque at each RPM as you suggest would complicate the math further. Sounds like a good dissertation for an automotive engineering student.

 

[AirCavHokie]

Is that also why the GFB DV+ makes sense? It doesn't add more peak hp/tq, but it makes boost available at lower rpm, right?

Someone could measure the boost of the stock valve versus the boost of the DV+ valve across the RPM range to see. Would that be easier than running both setups for HP and TQ on a dyno?

 

[Sonny Burnett]

It actually starts in the atmosphere. Back in the '60s, when I learned to drive, you had to have adjustments made if you were moving from Houston to Denver, due to the change in altitude, and resulting difference in oxygen density. Now cars make automatic adjustments for altitude.

That's where I screwed the pooch, yes atmospheric pressure along with weather and elevation, hence the old MAP sensors

Did I just read 20 wtq claims now in this thread as well??