Added a K&N air intake to the F-150....Wow!

[Capt Steve]

With the addition of the new trailer, just under 4K lbs, and a lot of serious mountains planned for our next trip to Northern Arizona/Southern Utah I decided to add a K&N air intake system to the 5.4 liter V-8. You can buy them on the internet cheaper than anywhere else, I got mine for $319.99, no tax - no freight. My local mechanic put it on and billed me $85 for one hour of labor, (it would have taken me three and I'm sure I would have screwed something up). (o; The dyno shows an increase of about 15 HP and the truck really feels like it is running/breathing better.

When I saw all of the crap that came off the motor to make way for the far simpler, cleaner K&N system I was very impressed. An additional benefit is that the system comes with a K&N air filter that would have been around $75 stand alone. I am getting the same speeds with a couple hundred less RPM's. Haven't had the chance to do any towing yet but do expect to see significant improvement in performance and mileage. I'll have a full report/update after the upcoming trip but expect to see a significant improvement.

Here is what they removed:

Here is the completed K&N installation:

I am also considering opening up the back end by adding a Flowmaster/Magnaflow type of performance exhaust. Does anyone have any experience with these systems? Any recommendations?

 

[ralph7]

smart to go w/the exhaust upgrade.
you are getting more air in, now you need to get more out.
your motor is basically an air pump. the more you flow, the better.
only downside of either mod is increased noise.
you already have noticed the intake bawooog sound, huh?

 

[Capt Steve]

smart to go w/the exhaust upgrade.
you are getting more air in, now you need to get more out.
your motor is basically an air pump. the more you flow, the better.
only downside of either mod is increased noise.
you already have noticed the intake bawooog sound, huh?

Yep, that's sort of what it sounds like, definitely different. I don't want to make the truck any louder than necessary but agree with your "air pump" analogy. I think the two systems will work well together...all I need is about another $400 to $500 but every time I come up with that much cash lately...I buy another gun. (o;

 

[ThirtyAcres]

Did the modification set off any "check engine" lights??

 

[Farmer17]

I had a 99 F-150 and put $300 Flowmaster exhaust on it, and couldn't really tell a difference. But I next put a K&N air filter on and it definitely seemed to have more pulling power when I towed my 19' Four Winns ski boat, and it was absolutely worth the money to me.

 

[snowman]

I'm glad that these units have performed well for you fellows; the one I installed on my F250 doesn't seem to make any difference. I like it that there is more room with all the stock apparatus removed, but that is about all I like about it. And having to clean the thing and re-oil it, for me, was a royal pain. Fortunately I don't drive the truck enough to have to do that very often.

I also have a Magna-Flow muffler, but that didn't help with power or mileage either.

Andy

 

[Capt Steve]

Did the modification set off any "check engine" lights??

Nope, no lights.... yet.

 

[DeadAye]

I am getting the same speeds with a couple hundred less RPM's.

Do What?
You changed the rear end too? New, different size tires? Transmission quit slippin' cause of the new air filter?

Intake/Exhaust and RPM per MPH have nothing to do with one another.... Think about it.

 

[kcode]

After you drive it for a while, please report back on your gas mileage, increase or decrease. I've debated on changing my F-150 to a CAI system, but couldn't justify the $300 to do it. When the truck was new, I had the Roush exhaust put on it with no change in gas consumption. Nice sound, but no change. I tow a race car and trailer around 5000 lbs.

 

[66TAS]

Go with the Magna Flow exhaust, increased flow and less noise than flow master, and when you really want to make a huge difference go here and get the proper bigger bore throttle body...you;ll thank me later...
BBK: Truck & SUV Throttle Bodies

 

[venomballistics]

smart to go w/the exhaust upgrade.
you are getting more air in, now you need to get more out.
your motor is basically an air pump. the more you flow, the better.
only downside of either mod is increased noise.
you already have noticed the intake bawooog sound, huh?

exactly .... now bolt on some headers, an X pipe and dual exhaust ... stick a procharger and intercooler into that K&N system and prepare to move what mountains may stand in yer way

 

[venomballistics]

Do What?
You changed the rear end too? New, different size tires? Transmission quit slippin' cause of the new air filter?

Intake/Exhaust and RPM per MPH have nothing to do with one another.... Think about it.

torque plays a role in RPM at cruise in an auto tranny.
it can tell you if you have minor issues when the RPM climbs for a given speed.

 

[Capt Steve]

torque plays a role in RPM at cruise in an auto tranny.
it can tell you if you have minor issues when the RPM climbs for a given speed.

That's my understanding. More HP and more torque = the engine working less hard to produce the same result. My observations are obviously subjective and admittedly premature since I just put it on but it sure seems to run/breath better. All that I have read indicates that I will get the additional power without any increase in fuel consumption and perhaps even increased fuel economy due to the greater efficiency. If it just kicks down out of overdrive less often due to the increased power/torque that will surely translate into greater MPG. YMMV (o;

 

[scooter123]

Personally I am not the least bit impressed with the current Ford 5.4 Triton. At work we currently have an F250 for a utility/errand truck and I had to drive it to a vendor to check out some issues he was having. Merging on the freeway it felt like an old Pinto 4 banger compared to the Chevy 2500 we had previously. Fact is that Vortec 350 in the Chevy was a darned hot number and that truck would do a peg legged burnout for a very loooong time. If you have to have a Ford, get the diesel, when chipped 600 hp is simple. As for the 5.4 gas engine, the only real solution for it's lack of torque is a supercharger and those aint cheap.

 

[beemerphile]

Do What?
You changed the rear end too? New, different size tires? Transmission quit slippin' cause of the new air filter?

Intake/Exhaust and RPM per MPH have nothing to do with one another.... Think about it.

Agree with this. I have made some pretty radical power changes to engines with auto trans and the speed / RPM relationship is unchanged at cruise. Also, lots of tests have shown that the K&N filtering is not as good as stock. This is a sensible part of an engine hop-up program but it is what it is.

 

[ralph7]

Agree with this. I have made some pretty radical power changes to engines with auto trans and the speed / RPM relationship is unchanged at cruise. Also, lots of tests have shown that the K&N filtering is not as good as stock. This is a sensible part of an engine hop-up program but it is what it is.

the k@n filter isn't as efficient a filter as stock. that is why it flows more air.
it still filters out enough airborne impurities to keep an engine healthy throughout it's lifetime. they have been around a long time and have a great reputation.
noisy-yes
pain in the ass to clean-yes
more power and longevity-hell yes

 

[DeadAye]

more power and longevity-hell yes

Actually more power - YES
More longevity - NO. In fact LESS.
High flow filters give more flow by being less restrictive. Less restrictive means more little things get by the filter. Little things floating in oil grind interfaces up.... They get to work on the valve/valve seat interfaces and ring/cylinder wall interfaces before they even get to the fun stuff.
With a less restrictive air filter - if you want longevity - oil changes become a VERY FREQUENT thing.
These things are for race car engines. Some race car engines are rebuilt almost every week - NO BIG DEAL - Others as needed. It's just part of the game (and fun) of racing.
The nice K&N filter will help your engine breathe - BUT - the cost isn't limited to what you pay for the filter........

Another negative aspect of free flow air filters (for most, mostly male, drivers) is reduced fuel mileage. For some reason it's hard to keep your foot out of it when that foot is unleashing more power

AND
IF added torque is lessening your transmission's slip, I believe you need to have that trans rebuilt or replaced...... At cruise, in OD with the torque converter locked up there should be very little to no slip.
Personally, I abhor automatic transmissions. A very complex device that reduces efficiency and adds to the cost of the vehicle - How wonderful.

 

[JohnnieB]

For what it's worth: Silence is golden, or more correctly stated, silence costs you more gold.

Several years ago I replaced the stock paper element on the Northstar engine in my '96 DeVille with a K&N element and replaced the stock exhaust system from the catalytic converter back with the larger diameter pipes and less restrictive resonator and mufflers from a wrecked STS. The net result was slightly louder intake and exhaust tones in exchange for an approximate 10% increase in MPG. City went from 16 to 17 (7 miles roundtrip to and from work - never got above 35MPH, so it never shifted into OD) and Highway went from 25 to 28 (Typically 5 above posted limit on cruise control). I didn't measure performance prior to the changes, but it wasn't a slouch to start with and seemed to accelerate quicker after it was breathing better. Also, the "service Engine Soon" light would come on when I used mid-range instead of premium and after the changes in the intake and exhaust systems, it doesn't. (No - The light didn't burn out - it came on when the ERG valve got cantankerous.)

Between the improved MPG and about a dime per gallon less on fuel, the changes I made have paid for themselves many times over and I still get a kick out of seeing the heads of young guys swiveling around to see where the distinctive sounds of a high performance engine is coming from. Of course, I use the loud pedal sparingly, but since I've retired I seem to be having more flashbacks to my hot-rodding days back in the 60's.

John

 

[venomballistics]

High flow filters give more flow by being less restrictive. Less restrictive means more little things get by the filter. Little things floating in oil grind interfaces up.... They get to work on the valve/valve seat interfaces and ring/cylinder wall interfaces before they even get to the fun stuff.

True ... but there are two ways to lower restriction at the filter proper ...
you can either use a more porous material which would contribute to the pitfalls listed or you can increase the overall area to feed well filtered air.

I think the greater contributor to gains in his after market system is the deletion of all the convoluted restrictive duct work which does nothing for air quality and less for flow over a nice simple pipe to the throttle body now in effect.

 

[jframe]

Don't know what year that Ford 5.4 is, but my 2005 Mustang responded to a CAI, AND a custom tune out of a Diablo Predator hand held tuner. These two items working together will generally net around 25-30 horsepower AT THE WHEELS, not at the flywheel. The Predator also keeps the air/fuel ratio at a safe level to avoid a lean condition due to the cold air kit. Mustang 4.6 3 valve engines are EXTREMELY sensitive to airflow changes. Just a suggestion to the original poster to give these tuners a try. The horsepower gains are definitely there, and the the computers are adjusted safely to compensate. This was combined on my car with a free flowing Pypes axle back muffler system, and an off road H-pipe headpipe without catalytic convertors and a set of 4.10 gears in the rear end. Alabama has no emission inspection, so this may not be feasible on all vehicles, but the power increase is great and really seat of the pants felt, as well as an increase in mileage.