Apexi drop-in filter?
Jun 30, 2007, 11:58 AM
#62
Review
OK, I went ahead and bought the Ebay filter and did a back to back run comparing it to the stock airbox and stock paper filter (dirty filter, too).
Quick summary:
I got about the results that I expected: less pressure drop, but increase in IAT. Overall, even without a tune, the Ebay filter did show minor power gains, even with less timing and a richer AFR. With a tune, there would be more power to be found and even more so if a proper cold air box was built. (The test was done at low boost of only about 19psi peak, so higher boost levels and greater airflow would favor the cone filter because the pressure drop with the stock setup would continue to increase.)
Log Review:
In my comparison, I wanted to make sure that I logged intake air temperature and barometric pressure, since the true test of an intake/filter is to see the change in air density at the MAS. Intercooling has the final say after the turbo, but for the sake of this test, I was simply testing the two intake setups.
The downside to a cone filter that doesn't have a cold air box is the increase in IAT. The downside to a stock airbox/filter is the fact that is is restrictive and causes a pressure drop. I remember doing some calculations a while back and came up with about 25* increase in IAT was about equal to a 1psi pressure drop (my math could be off). So, if your cone filter had 1 psi less pressure drop, but increased IATs by 25*, it might be a tie ballgame. Although, the higher the HP you make, and thus more airflow, the more and more the pressure drop would increase, where the cone filter may win out, even with increased IATs, since the increase in IAT shouldn't really change with increased airflow.
Anyway, in LogWorks I created a formula that will calculate the air density at the MAF for me. All I have to do is log the baro and IAT. I have also used the MAF scaling tables to calculate mass airflow, but I haven't done the two-byte mod for airflow, so my numbers are only good up to the 1600 Hz mark (if the calcs are accurate).
Here is the log(hard to see here...the solid lines are ebay filter, dotted are stock):
The first box shows the baro for both runs starting at 14.80 psi. By the end of the runs, the Ebay filter was at 14.43 psi and the stock setup was at 13.85 psi. A .37psi drop for Ebay, .95psi drop for stock setup.
Winner: Ebay air filter
The first box shows the IAT at the start of the run for stock setup was 35.3*C(95.9*F) and for the Ebay filter 30.1*C (86.16*F). By the end of the run, the stock setup was at 25.2*C(77.36*F) and the Ebay filter was at 31.3*C (88.32*F). An 18.54* drop in IAT for the stock setup...a 2.16*F increase for the Ebay filter.
Winner: stock airbox/filter
Note: In the middle of the run, the Ebay filter got up to 34.1*C(93.38*F), before slightly decreasing.
Note2: This is also with the stock cold air snorkel and airbox lid on top of the Ebay filter to help direct cooler air to the filter.
So which one was better? Well, by the end of the run, the stock setup showed and air density of 1.136 g/L and the Ebay filter showed an air density of 1.155 g/L. So, about a 1.7% increase in air density.
Overall winner: Ebay filter, with a slight increase in air density and slightly quicker acceleration through the run, even with less timing and a richer AFR during much of the run. I would imagine that as the boost levels increase, the Ebay filter would widen it's gap even more, since the pressure drop would just continue to increase on the stock setup. With a properly built cold-air box and a tune, the Ebay filter would gain a lot more over the stock setup.
Next, I will tune and build an air box and see what I get. Eventually down the road, I may even test a modified stock setup with the airbox lid cut out.
Eric
Quick summary:
I got about the results that I expected: less pressure drop, but increase in IAT. Overall, even without a tune, the Ebay filter did show minor power gains, even with less timing and a richer AFR. With a tune, there would be more power to be found and even more so if a proper cold air box was built. (The test was done at low boost of only about 19psi peak, so higher boost levels and greater airflow would favor the cone filter because the pressure drop with the stock setup would continue to increase.)
Log Review:
In my comparison, I wanted to make sure that I logged intake air temperature and barometric pressure, since the true test of an intake/filter is to see the change in air density at the MAS. Intercooling has the final say after the turbo, but for the sake of this test, I was simply testing the two intake setups.
The downside to a cone filter that doesn't have a cold air box is the increase in IAT. The downside to a stock airbox/filter is the fact that is is restrictive and causes a pressure drop. I remember doing some calculations a while back and came up with about 25* increase in IAT was about equal to a 1psi pressure drop (my math could be off). So, if your cone filter had 1 psi less pressure drop, but increased IATs by 25*, it might be a tie ballgame. Although, the higher the HP you make, and thus more airflow, the more and more the pressure drop would increase, where the cone filter may win out, even with increased IATs, since the increase in IAT shouldn't really change with increased airflow.
Anyway, in LogWorks I created a formula that will calculate the air density at the MAF for me. All I have to do is log the baro and IAT. I have also used the MAF scaling tables to calculate mass airflow, but I haven't done the two-byte mod for airflow, so my numbers are only good up to the 1600 Hz mark (if the calcs are accurate).
Here is the log(hard to see here...the solid lines are ebay filter, dotted are stock):
The first box shows the baro for both runs starting at 14.80 psi. By the end of the runs, the Ebay filter was at 14.43 psi and the stock setup was at 13.85 psi. A .37psi drop for Ebay, .95psi drop for stock setup.
Winner: Ebay air filter
The first box shows the IAT at the start of the run for stock setup was 35.3*C(95.9*F) and for the Ebay filter 30.1*C (86.16*F). By the end of the run, the stock setup was at 25.2*C(77.36*F) and the Ebay filter was at 31.3*C (88.32*F). An 18.54* drop in IAT for the stock setup...a 2.16*F increase for the Ebay filter.
Winner: stock airbox/filter
Note: In the middle of the run, the Ebay filter got up to 34.1*C(93.38*F), before slightly decreasing.
Note2: This is also with the stock cold air snorkel and airbox lid on top of the Ebay filter to help direct cooler air to the filter.
So which one was better? Well, by the end of the run, the stock setup showed and air density of 1.136 g/L and the Ebay filter showed an air density of 1.155 g/L. So, about a 1.7% increase in air density.
Overall winner: Ebay filter, with a slight increase in air density and slightly quicker acceleration through the run, even with less timing and a richer AFR during much of the run. I would imagine that as the boost levels increase, the Ebay filter would widen it's gap even more, since the pressure drop would just continue to increase on the stock setup. With a properly built cold-air box and a tune, the Ebay filter would gain a lot more over the stock setup.
Next, I will tune and build an air box and see what I get. Eventually down the road, I may even test a modified stock setup with the airbox lid cut out.
Eric
Last edited by l2r99gst; Jun 30, 2007 at 12:11 PM.
Jun 30, 2007, 01:15 PM
#63
^^ good write up 
. So in general it seems the Ebay setup doesn't throw the MAF readings to far off? I think for me the biggest reason to keep the stock box was because it didn't mess with the MAF readings and I wanted as few variables as possible.
. So in general it seems the Ebay setup doesn't throw the MAF readings to far off? I think for me the biggest reason to keep the stock box was because it didn't mess with the MAF readings and I wanted as few variables as possible.
Jul 2, 2007, 09:39 AM
#65
Hey guys, I figured I would ask this in here, since I got 0 replies in the turbo/drivetrain forum.
I will eventually get the Apexi power intake cone filter once I have some time to build a proper cold air box for it that would allow the use of the factory snorkel, but in the meantime, while I am still being lazy, I figured I would give a drop-in a shot with a modified airbox. Whether I keep it or not, it will be good for data's sake to compare to the stock setup.
I've been searching for a good dry-type drop-in, similar to how the Apexi cone filter is. I don't really want to use a K&N or Works, etc. Anyway, I found that Apexi makes a dry-type drop-in and they actually call it a power intake, which is the same name as their cone filter that performs so well.
Here is the thread that I started: https://www.evolutionm.net/forums/sh...d.php?t=277007
Does anyone have any info on this filter? I would like to give it a try if it is truly a drop-in form of the cone filter, meaning same materials, etc. If it is just a normal paper filter like stock, then I don't want to bother.
Thanks,
Eric
I will eventually get the Apexi power intake cone filter once I have some time to build a proper cold air box for it that would allow the use of the factory snorkel, but in the meantime, while I am still being lazy, I figured I would give a drop-in a shot with a modified airbox. Whether I keep it or not, it will be good for data's sake to compare to the stock setup.
I've been searching for a good dry-type drop-in, similar to how the Apexi cone filter is. I don't really want to use a K&N or Works, etc. Anyway, I found that Apexi makes a dry-type drop-in and they actually call it a power intake, which is the same name as their cone filter that performs so well.
Here is the thread that I started: https://www.evolutionm.net/forums/sh...d.php?t=277007
Does anyone have any info on this filter? I would like to give it a try if it is truly a drop-in form of the cone filter, meaning same materials, etc. If it is just a normal paper filter like stock, then I don't want to bother.
Thanks,
Eric
I have the Apexi drop-in filter. Bought it off of Ebay and had it shipped from Malaysia or HongKong. Cost was something like $70 (?? bought it last year) shipped.
Looking at the filter, the material looks like the OEM media, only red. There is an additional center support to keep the filter from sagging. Don't have a laptop, so I can't log, but at the strip, there was no difference between running the Apexi vs a dirty K&N.
Jan 30, 2008, 11:56 PM
#66
Bringing this one back from the dead. So one thing I was wondering about was whether or not anyone ever tried an ebay filter with the apex'i induction box?
Does anyone know if this will fit? Seems like it will offer the best of both worlds since you don't screw up MAF too much but you also get a shield away from the heat.
Edit. Eric...above you mention about building some kind of air box for it. Did you ever do it? And if so what was the outcome?
Does anyone know if this will fit? Seems like it will offer the best of both worlds since you don't screw up MAF too much but you also get a shield away from the heat.
Edit. Eric...above you mention about building some kind of air box for it. Did you ever do it? And if so what was the outcome?
Last edited by codgi; Jan 31, 2008 at 01:13 AM.
Jan 31, 2008, 06:19 AM
#67
I will do it eventually...seems like I do a lot of things at once, then don't do anything for a LONG time.My plan is just to purchase some plastic sheet and construct a heat shield as best I can. I know it will work as this is what I did on my turbo Eclipse years ago. It will definitely drop intake temps and you will have best of both worlds. In my Eclipse I used aluminum sheet and cut it up to fit and used metal reflective tape as well. This time I will use HDPE similar to the stock airbox or some other plastic that can easily withstand the temps.
Eric
Jan 31, 2008, 06:59 AM
#68
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Funny, I just found this thread and was going to revive it as well. Looks like codqi beat me to it!
I have been experiencing some lean condition issues with the cone filter I had, and finally just put the stock air box back in. Like NJ was saying above, I am lightly modded right now (see sig) and the biggest thing I got out of the cone filter was a lot of noise and some hesitation under heavy throttle. All of this is gone with the stock box, so I am considering something like the ARC induction box - does anyone have experience with this?
http://www.lancershop.com/customer/p...2&cat=2&page=1
I'm not sure if there is a cone filter underneath this, or if the box itself mounts directly onto the MAF. I'm looking for a solution that will give me better flow than the stock filter, but keeps the sound and hesitation I saw with the cone filter to a minimum.
I have been experiencing some lean condition issues with the cone filter I had, and finally just put the stock air box back in. Like NJ was saying above, I am lightly modded right now (see sig) and the biggest thing I got out of the cone filter was a lot of noise and some hesitation under heavy throttle. All of this is gone with the stock box, so I am considering something like the ARC induction box - does anyone have experience with this?
http://www.lancershop.com/customer/p...2&cat=2&page=1
I'm not sure if there is a cone filter underneath this, or if the box itself mounts directly onto the MAF. I'm looking for a solution that will give me better flow than the stock filter, but keeps the sound and hesitation I saw with the cone filter to a minimum.
Jan 31, 2008, 02:20 PM
#69
Bringing this one back from the dead. So one thing I was wondering about was whether or not anyone ever tried an ebay filter with the apex'i induction box?
Does anyone know if this will fit? Seems like it will offer the best of both worlds since you don't screw up MAF too much but you also get a shield away from the heat.
Edit. Eric...above you mention about building some kind of air box for it. Did you ever do it? And if so what was the outcome?
Does anyone know if this will fit? Seems like it will offer the best of both worlds since you don't screw up MAF too much but you also get a shield away from the heat.
Edit. Eric...above you mention about building some kind of air box for it. Did you ever do it? And if so what was the outcome?
At that point you could just mod your stock airbox to work with the filter and bring fresh air from outside like this:
Jan 31, 2008, 08:09 PM
#70
razorlab,
I can't tell from your pictures, but is the bottom of the box or any sides cut in any way? If not, then you still have the restriction of the stock airbox and the resulting pressure drop. A big restriction in the stock setup is really due to the stock airbox and the snorkel being the only path for air entry. That's why cutting the side of the box is a common and helpful mod if using a panel filter.
I just wanted to get clarification for anyone wanting to try this.
Eric
I can't tell from your pictures, but is the bottom of the box or any sides cut in any way? If not, then you still have the restriction of the stock airbox and the resulting pressure drop. A big restriction in the stock setup is really due to the stock airbox and the snorkel being the only path for air entry. That's why cutting the side of the box is a common and helpful mod if using a panel filter.
I just wanted to get clarification for anyone wanting to try this.
Eric
Jan 31, 2008, 11:24 PM
#71
No, I still haven't done it. I've barely touched my car in the last year or so. Too many other things are taking up my time and money. I will do it eventually...seems like I do a lot of things at once, then don't do anything for a LONG time.
My plan is just to purchase some plastic sheet and construct a heat shield as best I can. I know it will work as this is what I did on my turbo Eclipse years ago. It will definitely drop intake temps and you will have best of both worlds. In my Eclipse I used aluminum sheet and cut it up to fit and used metal reflective tape as well. This time I will use HDPE similar to the stock airbox or some other plastic that can easily withstand the temps.
Eric
I will do it eventually...seems like I do a lot of things at once, then don't do anything for a LONG time.My plan is just to purchase some plastic sheet and construct a heat shield as best I can. I know it will work as this is what I did on my turbo Eclipse years ago. It will definitely drop intake temps and you will have best of both worlds. In my Eclipse I used aluminum sheet and cut it up to fit and used metal reflective tape as well. This time I will use HDPE similar to the stock airbox or some other plastic that can easily withstand the temps.
Eric
Jan 31, 2008, 11:27 PM
#72
razorlab,
I can't tell from your pictures, but is the bottom of the box or any sides cut in any way? If not, then you still have the restriction of the stock airbox and the resulting pressure drop. A big restriction in the stock setup is really due to the stock airbox and the snorkel being the only path for air entry. That's why cutting the side of the box is a common and helpful mod if using a panel filter.
I just wanted to get clarification for anyone wanting to try this.
Eric
I can't tell from your pictures, but is the bottom of the box or any sides cut in any way? If not, then you still have the restriction of the stock airbox and the resulting pressure drop. A big restriction in the stock setup is really due to the stock airbox and the snorkel being the only path for air entry. That's why cutting the side of the box is a common and helpful mod if using a panel filter.
I just wanted to get clarification for anyone wanting to try this.
Eric
I'll try and take a photo of how it's cut. It's basically a frame for the lid of the box and the snorkel. It was my way of keeping the engine bay stealth and feeding the open filter some cooler air as I was having some intake temp problems on track with just the open filter.
