[E90jacob]

Short answer yes.

I'll be using a stock n52(230bhp) as an example in this write out.

I ran an experiment today to test the intake pressure with and without the air scoops to see the difference.

The testing conditions were exactly the same, same wind speed, cruise control, same road, same DIRECTION, everything was the same other than the testing variable. I ran the car at 25mph, 50mph, and 75mph on cruise control.

No scoops\/ Scoops\/
25mph: 2.02psi 25mph: 2.20psi
50mph: 2.68psi 50mph: 2.90psi
75mph: 4.37psi 75mph:4.99psi
Scoops offered:
25mph: .18psi more
50mph: .22psi more
75mph: .62psi more

Given that you stand to gain 7% of bhp from every psi into the engine, we can estimate the given hp gain for each speed.

The scoops results: 25mph=2.94hp=1.96whp
50mph=3.61hp=2.40whp
75mph=10.16hp=6.77whp

The math:
On avg you gain 7% more engine power with 1 psi then for every .14psi you gain 1% engine power.

.22psi is 1.5% engine power. 230hp x .015= 3.61hp.
Given that the drivetrain loss for the e90 328 is 15% of input engine power, 3.61hp / 1.5= 2.40whp.
Repeat the math for all psi of each speed and there's your result.

Edit: please note that these measurements were for a 328i. Turbo cars do not stand to gain anything from scoops. But the n51, n52, s65 all stand to gain hp.

ALSO none of these results show on a dyno, why? Because when you're sitting still, scoops don't do anything. The only way hp can be measured with scoops is to actually be driving and use wind speed. Simply put, the faster you drive, the more pressure the scoops build, the more pressure increases hp.

[The Nightman]

Great work and insight! After all these years, I think this is the only actual analysis of intake scoops that I'm aware of. My butt dyno felt that the scoops helped at highway speeds but I had no way of verifying. Now I'm curious how much of a difference the Dinan style air ram hose would make.

Where did you measure the pressure, and was throttle load the same for each comparison?

[E90jacob]

Originally Posted by Guy Fieri

Great work and insight! After all these years, I think this is the only actual analysis of intake scoops that I'm aware of. My butt dyno felt that the scoops helped at highway speeds but I had no way of verifying. Now I'm curious how much of a difference the Dinan style air ram hose would make.

Where did you measure the pressure, and was throttle load the same for each comparison?

Absolutely. The psi was measured using an obd reading software on my laptop, the test were all performed in set gears with cruise control so the throttle load was the exact same for both tests.

I literally just did the dinan ram air hose today!
My results came out to 3.6whp at 75mph. Although it's not a lot, that's only measure the boost in pressure it makes. The ultimate power gain from that mod would be the extra inlet and air that is offered once the throttle is 100%. In short the breathe ability helps more for power.

I just read a write up of a guy doing the dinan ram air mod and he made 9whp on a dyno… wind speed is nonexistent on a dyno so I can tell you with confidence that it provides 9whp and more the faster you go.

[E90jacob]

Originally Posted by Guy Fieri

Great work and insight! After all these years, I think this is the only actual analysis of intake scoops that I'm aware of. My butt dyno felt that the scoops helped at highway speeds but I had no way of verifying. Now I'm curious how much of a difference the Dinan style air ram hose would make.

Where did you measure the pressure, and was throttle load the same for each comparison?

Here my measure Kent's for the dinan test. Keep in mind this was only measuring wind speed and boost in intake psi. This doesn't measure the available breath ability

[MOD.Works]

Great research.
I like to do something similar myself.

Why not just measure the air mass? And full rpm range?
The scoops give a bit more power, just like the "mr5/Dinan" mod does. But it would be nice to see a full rpm range to WOT pull.



Another thread where you have studied silicone elbow results. I myself noticed that the silicone elbow flows a little better in a certain rpm range, but makes a small drop somewhere after 6000rpm.
The OE intake tube does not make a drop, although it flows a little worse.
The WOT 2000-7000rpm pull would be nice to see a comparison between silicone and OE elbow to Log intake manifold pressure and air mass. I think this would show up, a resonance that makes a small drop after 6000rpm.
I tried aluminum elbow and short silicone hoses. This helped a slight to no drop after 6000rpm.




I also need to enter the intake manifold pressure in my Logs.

[Hotter]

Which scoops did you use?

[Phil325i]

For what it's worth:

[Tambohamilton]

There's a problem with this: scoops will make most difference at high road speed but low intake velocity. As MOD says, you'd be better measuring MAF and doing full sweeps in a range of gears to get a more accurate picture

[E90jacob]

Originally Posted by Hotter

Which scoops did you use?

Standard ecs scoops. (I heard the red ones give you 5 more hp,jk)

[E90jacob]

Originally Posted by Tambohamilton

There's a problem with this: scoops will make most difference at high road speed but low intake velocity. As MOD says, you'd be better measuring MAF and doing full sweeps in a range of gears to get a more accurate picture

Ok ill do that then. I'll report back tomorrow with my findings.

[Hotter]

Originally Posted by E90jacob

Standard ecs scoops. (I heard the red ones give you 5 more hp,jk)

They are quite expensive, for the piece of plastic.

[rjahl]

Originally Posted by E90jacob

Absolutely. The psi was measured using an obd reading software on my laptop, the test were all performed in set gears with cruise control so the throttle load was the exact same for both tests.

I literally just did the dinan ram air hose today!
My results came out to 3.6whp at 75mph. Although it's not a lot, that's only measure the boost in pressure it makes. The ultimate power gain from that mod would be the extra inlet and air that is offered once the throttle is 100%. In short the breathe ability helps more for power.

I just read a write up of a guy doing the dinan ram air mod and he made 9whp on a dyno… wind speed is nonexistent on a dyno so I can tell you with confidence that it provides 9whp and more the faster you go.

Specifically what sensor did you pull up with the ODB? The DME is capable of reading MAP through ODB but that would difficult. It's after the throttle body and If I'm not mistaken the MAP is designed for vacuum with an effective range between (1000-250 millibar). The upper reporting limit is around 3 PSI.

If I was logging this, I would use the MAP, AIT, vehicle speed, RPM and MAF reporting through something like Test-0 or Bimmergeeks software. You'll get 120 milisecond frame rate and all the data would be stored in a spread sheet.

[beverage]

Is there a "supporting mods" statement to be had here too? Is this on a 3Stage manifold or standard non DISA intake manifold?

[AmuroRay]

Originally Posted by E90jacob

Short answer yes.

I'll be using a stock n52(230bhp) as an example in this write out.

I ran an experiment today to test the intake pressure with and without the air scoops to see the difference.

The testing conditions were exactly the same, same wind speed, cruise control, same road, same DIRECTION, everything was the same other than the testing variable. I ran the car at 25mph, 50mph, and 75mph on cruise control.

No scoops\/ Scoops\/
25mph: 2.02psi 25mph: 2.20psi
50mph: 2.68psi 50mph: 2.90psi
75mph: 4.37psi 75mph:4.99psi
Scoops offered:
25mph: .18psi more
50mph: .22psi more
75mph: .62psi more

Given that you stand to gain 7% of bhp from every psi into the engine, we can estimate the given hp gain for each speed.

The scoops results: 25mph=2.94hp=1.96whp
50mph=3.61hp=2.40whp
75mph=10.16hp=6.77whp

The math:
On avg you gain 7% more engine power with 1 psi then for every .14psi you gain 1% engine power.

.22psi is 1.5% engine power. 230hp x .015= 3.61hp.
Given that the drivetrain loss for the e90 328 is 15% of input engine power, 3.61hp / 1.5= 2.40whp.
Repeat the math for all psi of each speed and there's your result.

Edit: please note that these measurements were for a 328i. Turbo cars do not stand to gain anything from scoops. But the n51, n52, s65 all stand to gain hp.

ALSO none of these results show on a dyno, why? Because when you're sitting still, scoops don't do anything. The only way hp can be measured with scoops is to actually be driving and use wind speed. Simply put, the faster you drive, the more pressure the scoops build, the more pressure increases hp.

I actually noticed this (with no logs) when I have my E90 form the seat of the pants. Good to see the logs show the same.

[E90jacob]

Originally Posted by beverage

Is there a "supporting mods" statement to be had here too? Is this on a 3Stage manifold or standard non DISA intake manifold?

This is on a Fbo 328 so three stage

[E90jacob]

Originally Posted by rjahl

Specifically what sensor did you pull up with the ODB? The DME is capable of reading MAP through ODB but that would difficult. It's after the throttle body and If I'm not mistaken the MAP is designed for vacuum with an effective range between (1000-250 millibar). The upper reporting limit is around 3 PSI.

If I was logging this, I would use the MAP, AIT, vehicle speed, RPM and MAF reporting through something like Test-0 or Bimmergeeks software. You'll get 120 milisecond frame rate and all the data would be stored in a spread sheet.

The measurements were taken by using mass air flow and converting it to psi, from there I was able to see how much more air flows to the sensor. Even though the sensor is infront of the elbow, the effects of drag and airflow essentially suck up more air. So the sensor still reads accurately

There's no definitive proof that the scoops make any power other than my tests, but common sense tells us all yes, when you put scoops where there was no air guides before, it helps airflow where you want it.

[AmuroRay]

Now try at WOT

[rjahl]

Originally Posted by E90jacob

The measurements were taken by using mass air flow and converting it to psi, from there I was able to see how much more air flows to the sensor. Even though the sensor is infront of the elbow, the effects of drag and airflow essentially suck up more air. So the sensor still reads accurately

There's no definitive proof that the scoops make any power other than my tests, but common sense tells us all yes, when you put scoops where there was no air guides before, it helps airflow where you want it.

OK, please help me out. The DME is reporting MAS in Kilograms per hour, Actual units used. What conversion factor are you using to get PSI or pounds per square inch?

I can't get my head around the math and assumptions you would need to make. Without knowing the actual, intake pressure and air velocity, Air temp I can't get to absolute PSI.

[Tambohamilton]

I think he means MAP and bar to psi

[rjahl]

Originally Posted by Tambohamilton

I think he means MAP and bar to psi

Even then I don't see it.

Pretty sure the MAP sensor will not show positive pressure beyond a 2 or three PSI. it's also behind the throttle body. No way to get accurate intake / scoop pressures from there.

I've also done the math, a few times. 70 MPH can not create 4+ PSI.

Far better to show the actual data logs from the DME. MAS,MAP, AIT,RPM, LOAD, vehicle speed.

[E90jacob]

Originally Posted by rjahl

Even then I don't see it.

Pretty sure the MAP sensor will not show positive pressure beyond a 2 or three PSI. it's also behind the throttle body. No way to get accurate intake / scoop pressures from there.

I've also done the math, a few times. 70 MPH can not create 4+ PSI.

Far better to show the actual data logs from the DME. MAS,MAP, AIT,RPM, LOAD, vehicle speed.

70mph does not create 4 psi. Idk what part you miss read but go reread y original post.
At 75mph the maximum gain in intake box pressure was .62psi.
.62psi is good enough to generate a 10.16hp(crank) gain. Of course this is based off of the wind speed. And that's not always exact or consistent.
Given that the 328i e90 AT has an avg of 15% drivetrain loss, you get 8.6whp. Assuming this is all on the lower end. The average is 6.77whp

[E90jacob]

I would much rather someone else do these tests to find the same results. I'm getting busy at work and don't have access to redo all these tests.