Flow Bench Test Results

[Jim Allen]

Originally Posted by jimmyv13

I have datalogged many hours of intake air temps with turbo vehicles comparing different intake configurations. One thing I noted, the metal intake tubes almost ALWAYS had a higher intake air temp than plastic intake tubes, in the engine bay or not, regardless of filter or intake routing.

I agree, but what I was saying it isn't a significant amount in the context of an F150. You really are comparing apple to oranges when juxtaposing a turbocharged race engine with a work-a-day F-150 with a few mild mods. Five to ten degrees, even 15 degrees, is really insignificant on a street vehicle and, according to the informed people I have discussed this with, that's the differences we are talking about between plastic and metal. What little info I gathered in a previous search project seemed to bear this out, however, I'm always willing to review contrary data and change my mind!!! FWIW, the metal-tubed AEM I have installed now delivers about 6 degrees cooler IAT than the stock system, as measured by the Gryphon, via the IAT sensor. I doubt that small amount is doing anything much but it's somewhat noteworthy in this discussion, at least.

Originally Posted by jimmyv13

I wonder how a K&N compares to the AEM and stock filter? My stock filter needs replacing and I'm curious if I should get a K&N or a motorcraft? I didn't like the flexibility of the downspout connector and it sounds as if it may be detrimental to the flow if it collapses, so something else is going to go there.

I was long a K&N (or oiled cotton gauze- OCG) guy, but no more. I'm not satisfied the questions about filtering ability have been properly answered... yet... and I proved the (lack of) filtering issues to myself in one situation. On a street vehicle in a clean atmosphere, these may not be serious issues, but my trucks live in dirty environments. When I put a dab of grease on the clean side of the intake on my late-great trail rig (the Bum-V) and it's gritty in 6K miles on the street and trail, it's time for a change! I installed a tractor filter & housing from a 600ci tractor, with a synthetic/cleanable element and a cyclonic feature. But I'd rather have a little less clean air than more dirty air. Plus I get nervous when people start arguing about how much dirt is insignificant.

The AEM, and some others, are significantly better at filtering ability than an OCG design, which are typically at the bottom of that Totem pole... and OCGs rely heavily on the person who cleans and oils them to do it correctly. Other OCG filter naysayers mention the over-oiling/fouled MAF sensor issues, but I think those concerns may be somewhat overstated (and subject to the person applying the oil). I'd run the Motorcraft or the AEM. When we tested the main airbox alone, (#4 & 5) I think that showed the true airflow difference between those filters was minimal. I like the idea of a filter I can clean and run forever, but one that can catch stuff smaller than gravel.

[jimmyv13]

Originally Posted by Jim Allen

I agree, but what I was saying it isn't a significant amount in the context of an F150. You really are comparing apple to oranges when juxtaposing a turbocharged race engine with a work-a-day F-150 with a few mild mods. Five to ten degrees, even 15 degrees, is really insignificant on a street vehicle and, according to the informed people I have discussed this with, that's the differences we are talking about between plastic and metal. What little info I gathered in a previous search project seemed to bear this out, however, I'm always willing to review contrary data and change my mind!!! FWIW, the metal-tubed AEM I have installed now delivers about 6 degrees cooler IAT than the stock system, as measured by the Gryphon, via the IAT sensor. I doubt that small amount is doing anything much but it's somewhat noteworthy in this discussion, at least.

Very interesting info with the AEM metal intake. Has AEM made a change in their products? I seem to remember that company making junk products for a while.

My research was done on a daily driven turbo RX-7 with an intake and exhaust. Nothing extraordinary, just a normal vehicle that I drove everyday to and from school.

[jimmyv13]

Originally Posted by Jim Allen

Also 88Racing: I not clear on what you mean by "more air thru the stock setup" ? Yes the stock Motorcraft air filter seemed to flow a little more than the AEM panel. Was that what you mean? Or was it that the stock setup was very close to the modified system. Note that in #6, we removed the rubber downspout adapter and that's when the modified system exceeded the stock by a little.

Did you notice the downspout fluttering during the testing that would indicate a lower CFM? I am curious as to why it flowed better without the connector?

[Jim Allen]

The "puckering" only occurred when tested at 20" of H20, not at 10". The actual airflow is then converted via a graph to 28". In the case of the 10" tests, there is less air actually flowing through the unit, so the puckering was not apparent. Still, the unit flowed better without the rubber when tested at 10" of H20. The corrected 10" reading were 607cfm with, and 642.5 cfm without the rubber. At 20" the readings were 586.69/632.5. That says to me that the rubber over the bell mouth of the adapter is doing something to the airflow.

[kd4crs]

Sorry I have been absent, our family is on vacation this week and have not been monitoring the forums. First, thanks for testing the various setups and posting the results. I wondered about the flexibility of the PVC downspout adapter and you confirmed what I suspected, that it might bow inward with high flow. That is not good for airflow. I will see if there is anything else that can be substituted or if the downspout adapter can be modified, perhaps by shortening the length of the leading edge will reduce or eliminated the bowing effect. The lip of the downspout adapter is what actually holds the unit in place so cutting it off entirely would not work. Further research will be needed. In the meantime the best alternative is the reduced straight PVC/ABS pipe into the fender. Thanks again for the testing and the results.

[kd4crs]

I just got around to purchasing the alternate rigid 3 inch tubing that fordmt08 on f150online.com used for his intake modification and it looks like it will work well installed a couple of different ways. The tubing required is made by Spectre Peformance. It is part number 8741 for the black color (8742 is Red, 8746 is Blue, 8748 is Silver) and it is called: 3" Flexible Air Duct. It is priced ~$20 and should be available at O'Reilly Auto Parts and Autozone stores. I installed it completely collapsed using one of the two connectors that come with the kit to go into the fender inlet and using the downspout connector to connect to the stock flexible section. It fits perfectly and does not require any hose clamps. I will be testing it out with my Gryphon Custom 87 performance and Custom 87 towing tunes this week. This variation completely eliminates any possibility of the downspout connector collapsing or getting sucked inside out.

[Jackpine]

Glad to see you again, kd4crs. I like the looks of the new approach. Isn't this new tubing pretty similar to the "armadillo hide" looking stuff that you can find in most hardware stores for dryer ducting?

I remain convinced though, that despite Jim Allen's outstanding (and I mean that) tests of this mod, there are benefits to be had. I am absolutely certain I am getting better gas mileage than before - about +0.5mpg, to be precise. I can only attribute this to a more efficiently running engine. My driving habits have not changed.

- Jack

[kd4crs]

JackandJanet,

Hi, the Spectre Performance intake tubing is kind of like the dryer tubing but it is rigid and if you expand it, it stays in that position until you collapse it. It is actually designed as an intake product and does away with the DWV entirely. I have only heard 3 reports of the downspout connector having collapsed or turned inside out. I guess that is due to some of them being more flexible than others. I have run the DWV intake mod with the downspout connector on my trucks ever since I posted it with no issues. This new variation by formmt08 on f150online completely eliminates any possibility of collapsing or obstruction. I really like it so far.

[Punisher]

Does anyone know if these images/vids are available somewhere else now? The links below are no longer valid. I'd like to see the visuals that this thread keeps referring too. I know this was almost a year ago but some of us are just catching up.

Thanks,
-Punisher

Originally Posted by Jim Allen

The results are in! And with some very interesting results. First off, this material will be going into a future issue of a magazine (to be mentioned at a later date) but I'm giving you guys the results first because I got the idea from you and you deserve the credit. I take the risk of somebody burning me by using the info somewhere else, so that at least oughta bring me up to Double Whopper status!

Also, in the story I will credit you guys for the mod in whatever way you think is appropriate... and is politically correct for the magazine, of course.

WARNING WILL ROBINSON!

Look close at the two closeup pics to see what happens to the downspout tube at high flow rates, so all of you that have done this may want to trim most the the excess back, leaving just enough to center it in the fenderwell hole. This problem occurred at the maximum flow rate of the housing. It may not occur to a stock truck (see 5.4L theoretical airflow below) but it's probably worth the time to fix it.

The tests were performed by two classes at the University of Northwestern Ohio's High Performance Fuels Class, at their School of High Performance Motorsports, on a Superflow SF-600 flow bench. Each class double checked each result from their class, but each class used a slightly different protocols (both standards in the industry) and I have averaged the results.

NOTE: A 5.4L V8, given 90 percent volumetric efficiency, at 5500 rpm, needs 473 cfm of air. Giving it more than it needs at any given time doesn't necessarily offer any more power. Bear that in mind when reading these results.

Condition/ Average Airflow

1- stock housing & filter, as installed in vehicle- 621 cfm
2- same as #1 but with AEM filter panel- 592.36 cfm
3- stock housing & filter but no silencer or snorkel- 656.83 cfm
4- same as #3 but with AEM panel filter- 632.50 cfm
5- same as #1 but with snorkel tube modification- 597.3
6- same as #5 but with rubber downspout adapter removed- 637.5 cfm
7- same as #5 but with AEM panel filter- 569.51 cfm
8- same as #6 but with AEM filter panel- 619.70 cfm
9- same as #3 but with silencer only- 632.50 cfm
10- Brute Force Intake (for 2004 model)- 733.30 cfm
11- AEM filter only- 1077.25 cfm

You can reach your own conclusion over what this all indicates and I will share mine later if asked

[88Racing]

Originally Posted by Punisher

Does anyone know if these images/vids are available somewhere else now? The links below are no longer valid. I'd like to see the visuals that this thread keeps referring too. I know this was almost a year ago but some of us are just catching up.

Thanks,
-Punisher

That's up to the OP to repost.
Must have gotten lost when the forum crashed.