I have a 03' FX4 with a 5.4 and 3.55ls rearend. Cai and Exhaust and Gryphon using canned tunes. Using the tow tune the best 0-60 I got was a 8.62... After seeing people getting mid 7s to high 7s, to me that is horrible.. And I don't break traction either.. Feels like I lose power of the line, like it lags. And then it lags at 55mph..

My buddies 04' FX4 with exhaust and Edge ran a 7.6, he just installed a CAI and ran a 7.2...

I just tried 93 octane and I was getting 8.3-8.7 on the 93 canned performance and 87 performance with the timing bumped up. Oh well, kinda glad I didn't sink money into a 93 custom performance with numbers that wont to move below 8, but it is still a big improvement from the 9 to 11's I got stock.

A little update..

Everything is the same but I have custom tunes. I was able to run a 0-60 in 7.8 seconds the other morning. Chirped my tires and that was on 87 perf. tune.

If 7.0-7.5 is normal.. I feel slow now. :cursin:

When you guys are getting low 7's, mid 7's is that on 91/93 oct perf. tune??

Maybe I should fill up with 91 oct and try my 91 oct perf. tune. And see if it is quicker..

Just to clarify things.
AZFX4 has a 5.4 2V 2003.
Longshot270 has a 4.6 2V 2004+?
Fordkindofguy has a 4.6 2V 97-03.

Not trying to single out AZFX4 but to my recall the most fx4's came with 3.73's
with limited slip?
I'm only going by what I used to own. I used to have an 03 fx4 5.4 2v 3.73 LS northland edition. Back in the day when I got it brand new the 3.73 was the only standard gear I could get.

AZFX4 Try your 91 custom perf tune and see how you do.

I've got a 2008 with the 3.55 LS. My best 0-60 time is an 8 flat. :twitch: I look at the 1/4 more because it covers more of the gears and power band. There I'm getting 16-16.2 consistently. Not the best times but my truck isn't for racing even if it does like to eat a ricer ever so often.:evillol:

Oh, my truck is a Supercab FX4 with 3.55ls..

Even with 3.73ls I would think I'd be quicker. But Supercab FX4's came with 3.55ls. Supercrew FX4's came with 3.73ls.. weird right? I thought I had the 3.73ls until 1 day my buddy told me his 03 FX4 was 3.55ls. I called BS, looked at axle code, it was 3.55ls! :doh:

AZFX4
3.55's weird?
I think mine had 3.73's because it was a "Northland Edition" now that you really got me thinking about it. Those were produced/manufactored in the Missouri plant back in the day.

I know right.. I was :cursin: off when I found out. That was 1 of the reasons I wanted the FX4 because of the 3.73ls.. Funny thing is. My buddies 97' F150 5.4 Supercab Offroad Package, he says it has 3.73ls. WTF. :cursin:

But it's no big deal really.. When I lift my truck and toss 35" tires on it, I'll regear to 4.56.

There you go that's one way to look at it.

Not to make you mad or anything i just programmed mine too tranny only and ran a 7.6 with slip in K and N, rear cat delete Dual in 1 out Flowmaster...
put it only 87 towing and ran a 6.8 :skeptic: so you tell me lol

oh yea mines 97 150 with 5.4 with 166k miles on it Orig everything...