CAI question
Posting Guru
Joined: Nov 2009
Posts: 2,016
Likes: 3
From: NC
The stock air box and filter for the 5.4L (without factoring any kind of forced induction) is more than adequate.
Running lean can also be caused by altering the geometry around the MAF (as well as a dirty MAF - such as oil from an oiled filter like K&N offers). The MAF is a thermal transfer device (more air across it means it cools faster) and in order to work properly it must know the cross-sectional area of the intake pipe. Some A/M intakes alter this geometry and thus screw up the MAF transfer function. A custom tune can fix this issue, but it requires extensive testing with a lot of vehicles or a dyno run with a wide-band O2 sensor.
If you search for "Gotts mod", you will see a simple and inexpensive (less than $10) way to reduce the restriction at the fender well. This is truly the only place you need to worry about. In fact, for the 09+ even this restriction was eliminated.
Any exhaust mods would have to include headers to add any gains. Cat-back changes on these newer trucks simply enhance the butt dyno sensitivity (louder must be better).
Running lean can also be caused by altering the geometry around the MAF (as well as a dirty MAF - such as oil from an oiled filter like K&N offers). The MAF is a thermal transfer device (more air across it means it cools faster) and in order to work properly it must know the cross-sectional area of the intake pipe. Some A/M intakes alter this geometry and thus screw up the MAF transfer function. A custom tune can fix this issue, but it requires extensive testing with a lot of vehicles or a dyno run with a wide-band O2 sensor.
If you search for "Gotts mod", you will see a simple and inexpensive (less than $10) way to reduce the restriction at the fender well. This is truly the only place you need to worry about. In fact, for the 09+ even this restriction was eliminated.
Any exhaust mods would have to include headers to add any gains. Cat-back changes on these newer trucks simply enhance the butt dyno sensitivity (louder must be better).
New User
Joined: Dec 2011
Posts: 7
Likes: 0
So I bought an 05 F150 King Ranch Crew Cab with the 5.4L V8 last October. I've had the truck more than a year now and I'm ready to step into the world of mods for the first time. The truck had a cat back 3.5" dual exaust installed when i bought it, I cut the muffler off the day after. I lucked into a free SCT X2 and was going to pair some tunes with a CAI. But if i understand you correctly youre saying I would be better off with the tunes and the GOTTS mod? What if I gutted out the cats? I live at 7000ft of elevation does this make a differece? Greatly appreciate any help.
Posting Guru
Joined: Nov 2009
Posts: 2,016
Likes: 3
From: NC
So I bought an 05 F150 King Ranch Crew Cab with the 5.4L V8 last October. I've had the truck more than a year now and I'm ready to step into the world of mods for the first time. The truck had a cat back 3.5" dual exaust installed when i bought it, I cut the muffler off the day after. I lucked into a free SCT X2 and was going to pair some tunes with a CAI. But if i understand you correctly youre saying I would be better off with the tunes and the GOTTS mod? What if I gutted out the cats? I live at 7000ft of elevation does this make a differece? Greatly appreciate any help.
Call Mike Butler at 5Startuning.com or you can PM him (fordmdb) about gutting the cats and custom tunes. And yes, 7000' elevation definitely makes a difference in your custom tunes.
Elder User
Joined: Nov 2009
Posts: 890
Likes: 1
Before my stroker rebuild for my 01 Bullitt I was getting 275HP and 300ft lbs to the ground with a CAI, headers, cat back (well...there's no cats), and a Brenspeed tune. Sure, now it's more like 320HP and 340 ft lbs but hey, it scares the camaro ss's from stoplight to stoplight.
Senior User
Joined: Apr 2006
Posts: 248
Likes: 0
From: Escondido, Ca
2004 and 2005 trucks have a very strict PCM strategy. No questions asked, any CAI will throw a CEL and the truck will run lean
2006-2008 trucks have a more relaxed PCM strategy. Some trucks can run a CAI and no problems. I ran a Volant on my 2006 and never had an issue.
Personally I would do the "Gotts" mod and save your money. If you want more power, pick up a SCT Tuner and get it custom tuned. It'll be cheaper than that CAI, and it will do way more to get you power than a useless CAI
2006-2008 trucks have a more relaxed PCM strategy. Some trucks can run a CAI and no problems. I ran a Volant on my 2006 and never had an issue.
Personally I would do the "Gotts" mod and save your money. If you want more power, pick up a SCT Tuner and get it custom tuned. It'll be cheaper than that CAI, and it will do way more to get you power than a useless CAI
Posting Guru
Joined: Nov 2009
Posts: 2,016
Likes: 3
From: NC
Ever used a wideband 02 sensor and measured your AFR?
Regardless, all your example means is you should have bought a lottery ticket 'cause you've been really lucky.
New User
Joined: Dec 2011
Posts: 7
Likes: 0
So after three days of research and some careful consideration...
I have confirmed through SCT that my SCTX2 will work fine on my truck, and so I have decided to pair it with an S&B CAI.
I picked this CAI because the air box seals completley and pulls cold air through the stock hole in the fender as well as from behind the headlight. Also some of my research showed that the problem alot of CAI's have that throw codes are from oiled filters sometimes cause problems with the MAS. This kit uses a dry disposable filter that is interchangable so I can go with the cotton filter later if I wish.
This paired with some custom tunes for my SCT X2 and my existing cat back exaust (sans muffler of course) should be a nice upgrade.
Thanks for the tips everyone!
I have confirmed through SCT that my SCTX2 will work fine on my truck, and so I have decided to pair it with an S&B CAI.
I picked this CAI because the air box seals completley and pulls cold air through the stock hole in the fender as well as from behind the headlight. Also some of my research showed that the problem alot of CAI's have that throw codes are from oiled filters sometimes cause problems with the MAS. This kit uses a dry disposable filter that is interchangable so I can go with the cotton filter later if I wish.
This paired with some custom tunes for my SCT X2 and my existing cat back exaust (sans muffler of course) should be a nice upgrade.
Thanks for the tips everyone!
Hotshot
Joined: Sep 2010
Posts: 10,459
Likes: 10
From: RVA
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Hotshot
Joined: Sep 2010
Posts: 10,459
Likes: 10
From: RVA
I cannot speak towards elevation as I'm pretty much at sea level. His tunes work nicely in my truck. PHP writes great tunes also, but their wait time is much longer than 5 Star's.
Go to SCTs site and see if there is a local shop that is familiar with truck tunes. That might be your best bet with your elevation needs.
Go to SCTs site and see if there is a local shop that is familiar with truck tunes. That might be your best bet with your elevation needs.
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