It may be influenced by where the stock gauge (the the "t" most of us tap from) is pulling its reading from.

Maybe they all have 10.5 lbs of boost, but there is a restriction in the plumbimg for the gauge that only shows 8lbs. Replacing the airbox with an open filter may alleviate this and cause the gauge to show the "true" reading.

maybe?

 

On warmer days (75*F) (like yesterday afternoon) I was seeing 8.5# of boost in 3rd. My L is currently "de-modded" except for 2 hi-flow cats, no pre-cats, and magnaflow muffler.

This morning I got about 10.5# of boost in colder air (48*F).

Cooler air, denser charge, more boost.

Open element filter, less restriction, more air, more boost. I will put on my open element filter tonight and take a test drive to see the difference.



...on a side not, it's REALLY weird driving the L back almost BONE STOCK! It DEFINITELY doesn't pull as hard as it used to. ...and I can't even hear the S/C!!!!

 

Tim, I have a feeling that you were probably reading close to 10.5 lbs stock. I agree that the air filter can't possibly add that much boost until the truck starts choking. Obviously, the truck is not choking stock or Ford would have modified the airbox to prevent that.

I don't remember the boost difference between the panel K&N and the stock paper filter, but I do recall that the assometer read higher when I swapped the stock panel for the K&N--just more responsiveness.

--Rip

 

i have a bone stock 03 and even in 75-80 degree weather i'm pushing 10psi at wot. when it gets colder i go past the 10psi mark......this unusual? the truck dosnt have a mod on it. Jim

 

Tim:

Here is what I posted awhile back under my old login name. It has g-tech results and later on timeslip results (typed as I had no scanner at the time).

https://www.f150online.com/forums/sh...threadid=45310

I saw a consistent .15 sec faster with the stock box. That could possibly be attributed to a very teeny diff in 60 ft. With that said, assume that the .15 sec is gone and both systems give me the same ET. Then there is NO gain to buying an open system that is not enclosed even though bosst is higher? I'll spend that $200 on something with known gains rather than a "whine-noise enrichener"

 

I' am lucky to just tag 10 lbs and it is -17 C up here

 

Changing from the stock air box with a K&N filter and a 4" hole cut in the bottom to one of Danny's (Swanson) filter kits I picked up 8 rwhp and 10 pounds of torque. That was on back to back dyno runs. Needless to say, I did not take the filter kit off! Skip

 

Did you pick up any boost? If so, how much?

I re-did the math. 2.5 lbs of additional boost from an air filter should be close to theoretically ideal, as the supercharger is not working one bit harder. A perfect PSIG on our trucks should be worth about 14 rwHP. So, a perfect 2.5 PSIG gain should produce 35 rwHP.

I am gonna break down and sacrifice the warranty soon. I am going to take the truck to Danny for some rigorous before-and-after dyno pulls. Jim Bell has famously stated that the rear wheel dyno is "a lie detector." I agree.

 

I have a stock L except for a Magnaflow Catback and I see 12# of boost or more on the stock gauge in 50 degree weather

 

timmy, I thought you had the big 3 mods already? chip filter n pulley!

jesus H christ

 

They do,
Why do you think the Filter is everyones 1st Mod.
On a S/C L it's good for prob 15-25 HP and lots say that in their ad's.

Example:
Lightning owners can enjoy greater benefits from their vehicle. Our system replaces the entire OEM airbox. Less restriction provides a solid 20 horsepower improvement compared to a stocker! CAD (Cool Air Dam) technology
provides the much needed dense air charge through the system. As much as 2mph gains have been noticed in quarter mile runs!

More air ='s Power
Colder Air is even better
AND NITROUS IS DA SCHITT

 

Like a dummy, I didn't take any boost readings. We all kind of stood around and said "That was easy hp". My stock guage never went very far and the needle seemed to be just a little higher after the install. Mine was one of the first ones to be put on and I am sure that Danny has data on the filter kits now. I waited till my truck was almost off warantee before I started messing with it. If I had to do it over again, I would drive the truck straight from the dealer to Danny's and let the fun begin. Skip

 

Not an option for me right now. I have a fairly pronounced knock, which I assume to be piston slap. Until I resolve this issue, the mods are out.

 

I just installed the Airaid kit and It is the sh*t. I had an oped filter from PSP and I was cool but the airaid actully has a wall around the filter to isolate it from the engine. Quaity of air is better but the whine noise is down. Dyno result show an 8 horsepower increase with the enclosed unit.

 

By the way I picked up a half a pound of boost, not much but hey!