My assumption would be that your assumption is wrong. I don't think the roush intake has a 4" ID, but I don't have one, so I could be totally wrong.

- NCSU

 

Jon I'm not familiar with that intake either but what is the smallest i.d. at any point in the system and the i.d. where the MAS is?

 

while this topic is open. I had earlier read some threads about getting the 3" and not the 3.5" but when i ordered mine it stated the 3" was for the 4.6 and 3.5 was for the 5.4. I chose to go with the 3.5 and the box showed up today. Roush off road should be here soon as well. I have not ordered tunes so should i hold off on the CAI install until i do or slap it on now and pray for the best.

2005 Lariat SCAB 5.4

 

Where did you order it from? The 3" and 3.5" both work on a 5.4L.

Absolutely do NOT install the intake without tunes!!! You should have been told that the 3.5" AF1 requires custom tuning to avoid running your engine lean.

You need to either order custom tunes, or exchange your 3.5" AF1 for a 3.0". The 3" does not require custom tuning to be run safely.

- NCSU

 

guess it will stay in the box for a while. From what i see many people are running troyer tunes. Is this pretty much what everyone recommends or superchips or some other tuner

 

So, I am going to order the 3" AF1 for my 2008, since the majority of the time I am driving unloaded, and then I can still run the stock tunes with the AF1 (3") while I wait for Troyer tunes. I have thought about the 3.5" because I did like the sound it made on my last F-150 and I think the extra power I could use when towing my 6,000# travel trailer. TP offers the tube only and will rewrite my three AF1 3" tunes for the 3.5" for about two bills. Do any of you know if I'll see enough difference in the 3.5" daily driving or towing to warrant the extra two bills? Or, should I just drive the truck with the stock intake towing for the eight weeks while I wait for TP tunes?

 

Smoke, I would not spend the money on the 3.5-inch tube. I went from the 3.5-inch to the 3-inch several weeks ago and now my 3.5-inch is collecting dust. I noticed no seat of the pants difference in power and I can send you a datalogged graph showing rpm/0-60 time of the 3.5 vs 3 and the spread was 7.81 vs 7.88 seconds respectively, and that was with the 1-2 shift 200 rpm lower on the 3-inch run. The runs were on different days but I think you get the idea. I like the idle and off idle tip in better from the 3-inch and don't notice any loss anywhere in the power band. The 3-inch sounds the same as the 3.5-inch except not quite as loud. You're same as me with daily driving and moderate towing which I find the 3-inch to be very capable and couple that with the low end power and great partial throttle response of Mike's tunes I think you will be happy with that set up. However it looks like you are coming out of a powerstroke and be sure that no 5.4 will touch that for towing.

 

Thanks, BlackDawg. You are right on target. I cut the 3" loose and think I'd rather spend the money on some additional tunes for fun and comparison. I'm really hoping to find an economy tune with some power, and it looks like Justin has some. I loved my TP tunes on the last 2007 F-150 I had, and the 93 octane performance actually gave me better mileage everyday than anything else... enough to pay for the $0.20 a gallon more fuel cost and then some. I still wish I had the Gryphon/Edge display, but I guess it's a bell and whistle deal for me as I have the Xcal2 and Scan Guage II to do all that stuff already.

 

I just havent had much time lately to pull the intake and take some measurements. This saturday I managed to get a couple hours for myself and finally installed the Offroad exhaust. Sounds sweet. Just what I was after. Still trying to align the tips to my satisfaction . (see Roush Hanger problem thread) . Im going to try to get it to a Dyno to find out how the A/F ratio is. So Im keeping my fingers crossed till then. Does anyone know how and if octain effects the ratio? When the time comes Im sure Ill be running on 93. I may run the 3 edge programs to compare the numbers . but this would all be done on 93 octain. This would give me a good starting point before I switch to Bills tunes.