Tested: Ebay Filter
A cold air box still needs some other opening besides the stock snorkel. The reason the stock box is so restrictive is because the only air opening to it is the stock snorkel. The cross sectional area of that is pretty small, resulting in the pressure drop that we see when logging with the stock box.
I don't know how much of an issue it will be with your cardboard box, since it definitely isn't an air tight design, but if you are getting more than about .4 psi pressure drop or so, then you need more room to breathe. The whole bottom of the box is basically open, though, right? I can't tell in the pics if the box has a bottom or how much of a bottom.
I'm just curious is you're getting more pressure drop with that design than if the box wasn't there.
I'm personally going to buy some plastic sheet, most likely HDPE and build my own box, too. It will have an opening for the snorkel, at at least another big opening somewhere else, whether it be on the opposite side of the engine, or on the bottom, etc. I want the cross sectional area of the 'breathing' openings to be at least as large as the cross sectional area of the MAF opening, possibly much larger.
Eric
I don't know how much of an issue it will be with your cardboard box, since it definitely isn't an air tight design, but if you are getting more than about .4 psi pressure drop or so, then you need more room to breathe. The whole bottom of the box is basically open, though, right? I can't tell in the pics if the box has a bottom or how much of a bottom.
I'm just curious is you're getting more pressure drop with that design than if the box wasn't there.
I'm personally going to buy some plastic sheet, most likely HDPE and build my own box, too. It will have an opening for the snorkel, at at least another big opening somewhere else, whether it be on the opposite side of the engine, or on the bottom, etc. I want the cross sectional area of the 'breathing' openings to be at least as large as the cross sectional area of the MAF opening, possibly much larger.
Eric
Last edited by l2r99gst; Jul 6, 2007 at 06:15 AM.
A cold air box still needs some other opening besides the stock snorkel. The reason the stock box is so restrictive is because the only air opening to it is the stock snorkel. The cross sectional area of that is pretty small, resulting in the pressure drop that we see when logging with the stock box.
I don't know how much of an issue it will be with your cardboard box, since it definitely isn't an air tight design, but if you are getting more than about .4 psi pressure drop or so, then you need more room to breathe. The whole bottom of the box is basically open, though, right? I can't tell in the pics if the box has a bottom or how much of a bottom.
I'm just curious is you're getting more pressure drop with that design than if the box wasn't there.
I'm personally going to buy some plastic sheet, most likely HDPE and build my own box, too. It will have an opening for the snorkel, at at least another big opening somewhere else, whether it be on the opposite side of the engine, or on the bottom, etc. I want the cross sectional area of the 'breathing' openings to be at least as large as the cross sectional area of the MAF opening, possibly much larger.
Eric
I don't know how much of an issue it will be with your cardboard box, since it definitely isn't an air tight design, but if you are getting more than about .4 psi pressure drop or so, then you need more room to breathe. The whole bottom of the box is basically open, though, right? I can't tell in the pics if the box has a bottom or how much of a bottom.
I'm just curious is you're getting more pressure drop with that design than if the box wasn't there.
I'm personally going to buy some plastic sheet, most likely HDPE and build my own box, too. It will have an opening for the snorkel, at at least another big opening somewhere else, whether it be on the opposite side of the engine, or on the bottom, etc. I want the cross sectional area of the 'breathing' openings to be at least as large as the cross sectional area of the MAF opening, possibly much larger.
Eric
https://www.evolutionm.net/forums/showthread.php?t=173392
A cold air box still needs some other opening besides the stock snorkel. The reason the stock box is so restrictive is because the only air opening to it is the stock snorkel. The cross sectional area of that is pretty small, resulting in the pressure drop that we see when logging with the stock box.
I don't know how much of an issue it will be with your cardboard box, since it definitely isn't an air tight design, but if you are getting more than about .4 psi pressure drop or so, then you need more room to breathe. The whole bottom of the box is basically open, though, right? I can't tell in the pics if the box has a bottom or how much of a bottom.
I'm just curious is you're getting more pressure drop with that design than if the box wasn't there.
I'm personally going to buy some plastic sheet, most likely HDPE and build my own box, too. It will have an opening for the snorkel, at at least another big opening somewhere else, whether it be on the opposite side of the engine, or on the bottom, etc. I want the cross sectional area of the 'breathing' openings to be at least as large as the cross sectional area of the MAF opening, possibly much larger.
Eric
I don't know how much of an issue it will be with your cardboard box, since it definitely isn't an air tight design, but if you are getting more than about .4 psi pressure drop or so, then you need more room to breathe. The whole bottom of the box is basically open, though, right? I can't tell in the pics if the box has a bottom or how much of a bottom.
I'm just curious is you're getting more pressure drop with that design than if the box wasn't there.
I'm personally going to buy some plastic sheet, most likely HDPE and build my own box, too. It will have an opening for the snorkel, at at least another big opening somewhere else, whether it be on the opposite side of the engine, or on the bottom, etc. I want the cross sectional area of the 'breathing' openings to be at least as large as the cross sectional area of the MAF opening, possibly much larger.
Eric
Basically this design does a couple of things. It blocks air in the engine from getting directly to the filter. It also uses the stock ram-air snorkel. In addition, the bottom is open, and cold air will be directed there with tubing, so pressure drop (restrictions in the turbo trying to get air) shouldn't be an issue

Oh, and the box is only $1.83 at your local UPS store
Last edited by Erik@MIL.SPEC; Jul 6, 2007 at 09:40 AM.
Sounds good, then.
The only thing you have to worry about now is the cardboard starting your engine bay on fire.
In a couple minutes of research (Google), I found a few plastics companies that will sell a sheet of HDPE, and other plastics, for under $10. A sheet of like 2'x4', so that should be enough to build a box with. I'll definitely give it a shot and see what happens. I may just keep the top open and try to seal it up to the hood with a rubber lining or something similar, or maybe a clear top, etc.
Did you happend to do any logging before and after your setup? I'm curious in IATs and baro.
Eric
The only thing you have to worry about now is the cardboard starting your engine bay on fire.
In a couple minutes of research (Google), I found a few plastics companies that will sell a sheet of HDPE, and other plastics, for under $10. A sheet of like 2'x4', so that should be enough to build a box with. I'll definitely give it a shot and see what happens. I may just keep the top open and try to seal it up to the hood with a rubber lining or something similar, or maybe a clear top, etc.
Did you happend to do any logging before and after your setup? I'm curious in IATs and baro.
Eric
Ok here is the BR filter (same type and size of filter as the EBAY) with the stock intake box modded to work so it will be a bit more stealthier for this wonderful state of Kalifornia. 
























