I have a 2002 F-150 with a 4.6l and I have added a Flowmaster exhaust, a K&N filter, a throttle body spacer and even added a Tornado and I'm disappointed with the results. I think the truck performed better stock than it does with these add-ons. Is anybody else having similar problems or have any suggestions of what I could do to regain my bottom end performance? I want to try to regain my bottom end before I try a chip or open air intake. Someone please help with any suggestions.

 

Hey man welcome! You running the stock tires?

 

Everything is stock except for what I mentioned. The thing just isn't as responsive as it used to be. Have any clues as to what it could be?

 

Just an offering here, but you may have to wait for the computer to re-learn your truck and driving habits after the mods. My performance seems to improve all the time after my Flowmaster and AirAid Filter additions. I'm sure that there is a point at which that will end..hehe

Just my usual .02 worth

 

Get rid of that tornado, those are HOAX's and you got sucked in...

Dan

 

DITTO.....get rid of that "tornado" device. It's not worth the box it came in, and the "turbulence" it is causing at your throttle body inlet may actually be causing a LOSS of power.....rather than the advertised power increase!!

 

I have the Airaid throttle body spacer too, wouldn't that offset any turbulance that may be caused from the Tornado?

 

How much hp increase do you think you gained with all those mods?

 

I concur on the computer learing issue. This is a HUGE deal. Now I don't know the specs on your Flowmater exhaust but if you went too big on tailpipe this could seriously curtail bottom end torque. Gotta keep those gasses flowing, especially with Flowmaster's "pulse-scavenging" technology. An over large tailpipe, or even just the outlet, can cause a low pressure zone that actually will somewhat stall the exhaist flow. This is most commonly seen at lower speeds and RPMs since you are not pushing as much exhaust.

I know it's a different vehicle but I put a Flowmaster 40 in my '91 4Runner and it made a huge difference with the 2" pipe. Later I went to 3" outlet just to be cool and the performance plunger well below how the stock unit performed.

 

Get the wrong tail pipe size and look out!! hummm.

 

I got the Flowmaster from a friend who had it on his F-150 before he crashed it and it already had a 3" pipe from the cat back so I just stayed with that. It sounded "cool" but I noticed a definite plunge in performance so I later took it back to a shop and had a 2.5" pipe put on from the Flowmaster back and I didn't notice much of a gain, if any. Would it help if I went down to 2"? I also need to know if the length matters because the 2.5" pipe stops about 18"-24" short of the stock pipe.

 

Well, since I'm a novice at all this it would be hard for me to gauge my gains, if any. I did let a friend try the 'Tornado' and while it was out of my truck I did notice a drop off in milage but none in performance. The 'Airaid' gave me smoother acceleration and more gain in the middle but I'm not sure about how much HP.

 

Ahh! A man with a purpose, I can appreciate that.