Finesse

The Brute Force kit is nicely made and includes everything here plus great instructions with photos. You can get them chromed or powder coated.

Getting the right amount of air into the engine, at the coolest temperature possible, is part of the power equation. There was a day when the OEM manufacturers failed this basic auto math miserably. The aftermarket built products that easily exceeded stock. Today, the OEM is doing a great job in that area, for the most part, and the aftermarket has to work lots harder. We had the opportunity to see how AEM meets that challenge when we installed a Brute Force Cold Air Intake (CAI) onto Blue, our ’05 F-150 test mule. We also had the opportunity to try out AEM’s replacement panel filter that fits into the stock intake.
Before we get into the two products tests, a few words on AEM’s Dryflow filters are in order. To improve filtering ability and eliminate the need for oiling, AEM went to a reinforced synthetic fiber media that can filter as fine as one micron. Independent tests at the Southwest Research Institute showed the AEM with a cumulative efficiency of 99.41 percent (air filter efficiency improves slightly as it gets dirty) using fine dust. This beat the worst performing oiled cotton gauze filters it was tested against by a solid 3+ percent and the best one by a percent. It also beats the oiled cotton filters in dust capacity by a big margin, in the neighborhood twice as much, before reaching a terminal restriction level.
The best feature of the Dryflow is that it needs no oil and is easily cleaned. Yeah, AEM has some special whiz-bang cleaner, but ordinary Simple Green seems to work just as well. Some of the tests performed by Southwest included determining how much filtering ability decreases with repeated cleanings, as well as deliberately abusing the filter while cleaning it. The performance of all washable filters degrade somewhat because you can’t get every particle out, but the Dryflow degrades less that other dry washable filters.
As an abuse test, an AEM filter was given the “Moron treatment.” First, it was soaked in used engine oil, cleaned with a harsh cleaner (brake cleaner and bleach) and then blown out the wrong way with high pressure air. With all that, the element still managed 97 percent cumulative efficiency.
With regards to airflow, AEM is the first to admit that some high performance filter media will outflow theirs. That higher flow media comes with a price... less filtering ability. To compensate, AEM sizes filters a little larger to suit the application. For example, our F-150 needs about 500 cfm to make 6,000 rpm. The filter on the Brute Force intake system we installed flows more than 1,100 cfm. The extra capacity allows for a dirty trail or for performance improvements that require more air.

Replacement Panel Filter

AEM makes cleanable replacement filters for some OEM applications, including our F-150. Flow capacity is 15-20 percent higher than stock, so it gives you a little over-capacity for mods. We ran the panel in the stock housing for several months and noted no change in fuel economy. To measure performance, we ran before and after 0-60 tests and they were essentially the same. This just proves that the stock filter has enough airflow in the stock housing to get the job done at the power levels we were running.
Whether the AEM panel filter will do any good performance-wise would depend on the ultimate flow of the stock Ford intake system housing and how much of a power increase it can support. It’ll likely run out of airflow in the housing before the filter runs out. For most people, the benefits will come from the forever aspects of the Dryflow and its ability to filter finer dirt particles.

1. After disconnecting the negative battery terminal, you’ll disconnect the PCV hose, unplug the MAF sensor, undo a few wiring clips and remove the snorkel and inlet duct.	2. The airbox is attached to the intake manifold with four bolts and it lifts off. Before setting it aside, remove the MAF sensor and save the screws as the MAF sensor reinstalls into the new inlet pipe. Note the warning about how it goes into the airflow and be sure to install the sensor in the right direction.
3. Install the rubber elbow onto the throttle body, followed by the short tube. Don’t fully tighten the clamps yet, as you’ll have to do some adjusting. You can hook up the PCV hose and MAF sensor.	4. You’ll install some adapters to an existing bracket and then mount the heat shield. The long tube attaches next, then the air filter. Once you have everything in position, you can tighten all the clamps and install the rubber gaskets on the heat shield.

Brute Force Installed

The Brute Force intake installs easily in little more than an hour. The instructions were complete and no hiccups were encountered. It fit like a glove. Be sure to disconnect the battery. Not only does this make the engine a bit safer to work around when unplugging EFI components, but it erases the adaptive memory. The new intake will add an unfamiliar element the PCM won’t expect. Most times, it simply readapts, which takes a large number of miles. Sometimes it will kick up a code. By erasing the memory, it quickly relearns the new parameters without having a hissy fit over it.

’04-08 Ford 5.4L Caveats

The ’04-08 Fords have some particular issues that has created some nightmares for the aftermarket. Because of the design and position of the Mass Air Flow sensor (MAF), these engines are very sensitive to intake mods. The wrong design can kick off a flurry of error codes. AEM spent the time necessary to keep the fuel trim within 1-2 percent of stock to prevent such events.
In addition, Ford made some programming changes that necessitated some design changes. AEM addressed these issues promptly with several changes to the Brute Force kits. If you install the wrong unit for your year, you could end up kicking up a MAF sensor-related EFI code. Currently there are two kits for ’04-08 F-150s, one for 2004 and some early 2005s, and another for 2005 and up. Weird things can also happen if you don’t disconnect the battery and erase the adaptive memory. You’ve been warned twice now!
There have been error code and pinging problems associated with combining a CAI with a programmer on the ’04-08 F-150s. The problem isn’t universal nor ever-present. Some canned tunes generally seem to work with some CAIs but sometimes an individual truck will have problems with a particular combo when others don’t. AEM reports relatively few such issues, mainly because of the care they took to match the factory trim. We have been using an Edge Evolution on Level 2 most often and haven’t had any issues. We have tried Level 3 for short periods with no issues but we make no promises you won’t have issues if you try our combo.

Brute Force Tested

Our truck already had some modifications, including a 3-inch Dynomax cat-back exhaust and an Edge Evolution programmer. The Brute Force made it’s presence felt on top of these, noticeable even by the ol butt-dyno. We were able to do before and after 0-60 tests and they confirmed what the heinie-meter was telling us. We knocked almost two tenths of a second off our averaged 0-60 times. We’ll take it!
Because we can measure intake air temp, we did so to see if the Brute Force lived up to the “cold” part of its job description. We’ve been monitoring the ambient vs intake temp a while now. We can count on about a 15 degree temperature differential between ambient air and intake air temp with the stock intake at about 60 mph. With the Brute Force, we are seeing an average of 9 degrees, so the AEM appears to be knocking off an extra 6 degrees off the intake air temp at the same speed.
We’re still early into our post CAI MPG testing. So far we are seeing about a 0.3 mpg increase, which occurs at our most economical cruising speed of 55 mph. Interestingly, we see that same jump at 70 mph but not much in between. We ran the truck long enough for it to adapt but some of that included our 0-60 runs. We’ve found that extended period of “Grampa” type driving offers a bit more opportunity to stabilize.
Intake noise is a concern to some folks. Like any free flow intake, the Brute Force is noisier than stock. While in the aforementioned “Grampa-mode” it isn’t obtrusive—barely noticeable in fact. We found it surprisingly quiet in “young-whippersnapper” mode. With a quiet exhaust it might intrude more. Our opinion is that if you prefer a quiet truck, you won’t be massively offended by the sound. If you want noise, you deaf fool, you won’t be completely disappointed but neither will you be overjoyed.

TEST STATISTICS
Fuel Economy Test Data Steady MPG recorded on Edge Evolution and tested on the same stretch of road, on the same day. Average taken over several weeks.

Condition	Steady 55 MPG	Steady 65 MPG	Steady 70 MPG	Overall MPG
Before	18.1	17.5	16.9	15.8
After	18.4	17.6	17.2	16.0