Two questions: (1), are they available for the 5.4 04s yet? And (2), do they really do anything for you? I have heard of increased horsepower and gas milage, but I am skeptical. Any thoughts?

 

I loved the 'induction growl' of the FIPK on my '97 5.4, but as to gas mileage/power I'm also doubtful in that specific application. We all know of some restrictive induction systems that may benefit from a K&N or similar filter.

 

this has been covered in many a thread recently. no, they are not available for the 04 yet. keep checking with K&N to find out when. probably early next year. as far as performance returns, they are definately worth th $50 for the filter. your engine will thank you for it. the FIPK is cool too. i plan on going with an FIPK when they become available.

 

OK, I'm an idiot. What's an FIPK?

 

FIPK = Fuel Injection Performance Kits

http://www.knfilters.com/

 

Are they worth the $300 dollars or so? Or would just an air filter work? Also, does it void the warranty on the vehicle?

 

I think the new 5.4 will really benefit from the FIPK when it comes out. The old 5.4 used a cone airfilter, the new 5.4 which flows alot more air uses a PANEL filter! Why ford did this is beyond me but I think a FIPK will turn the 3v 5.4 into a whole new animal.

 

it's worth the $250 if you want your engine to perform better and perhaps get better fuel mileage. it will give it more of a rumble too. i personally think it is very worth the money considering stock intakes can choke the engine even with Ford's new intake design. K&N is not the only manufacturer either. There is AEM, AFM, AirRad, Valant (spelling?) and others. K&N is known and is very good, but it isn't a one horse race here. The others deserve a good mention. And just so you know BigJim, FIPK is K&N's trademarked name, other companies have their names too, but in the end they are all aftermarket intake kits.

 

There remains the question of going the FIPK route or just replacing the stock filter. I just ran some quick volumetric numbers on the stock system for the 5.4. In stock form, the air intake tube is inducting approximately 11.45 square inches of air into a filter of approx. 58.5 square inches...that's mucho volume for 331 cubic inches of engine displacement. And, don't forget, it's all exiting via a single 3 inch exhaust pipe. The real question is the efficiency of the stock filter vs. say, a K&N. Probably no dispute that the K&N is more efficient (i.e. less restrictive). Thus, score one for K&N (or similar). But, as to an FIPK, I think calculations will show that what you're buying is just something to admire when you open the hood.

Also, it's doubtful that a replacement induction system (say K&N) would incorporate the stock expansion chamber benefits (see reply on forum page 2 to rocketir's RAM AIR question).