I have been having this debate with myself lately... my thoughts are as follows:

6.0L-based stroker
PROS- less expensive than most any form of forced induction, can be built to handle whatever I want to throw at it
CONS- more work than installing a Radix or turbo kit, would have to spend a considerable amount of time collecting parts and dealing with the machine work, etc...

Radix or other forced induction
PROS- for a given power/torque level will be more mild than a stroker motor (read: a stroker motor that puts 400 lb/ft to the wheels will be more radical than the boosted 5.3L; the stroker won't idle as well, and there may be some low speed drivability issues like cam surge, etc...), (relatively) simple weekend install (for the Radix)
CONS- Radix can only be pushed so far before it becomes inefficient (would rather have a screw-type blower than the Eaton; the STS kits make me uncomfortable, and the Combination Motorsports kit doesn't seem to exist any more), more expensive than stroker, tuning included w/ Radix seems to be for ****

Either way, you're looking at having to do transmission work to get it to hold, and with either the stroker or the Radix you're looking at a chunk of change for headers if you want to get the most out of your setup. Ideally, I'd like to do both a (CM) turbo kit and a stroker... but by the time I got it built, tuned, and found a transmission to hold it all, I'd have $12k or better in it.

 

there's a little more to it than that, but you got the jist of it.

 

Ford designs those motors for low end torque. The intake ports flow more like those gm swirl port TBI heads then a gen III. Just compare the flow #'s from Patriots website.

http://www.patriot-performance.com/SOHC.htm

1.7" intake 1.4" exhaust valves

Small bore, long stroke 3.55" bore 4.00" Stroke

I repair a fleet of 75 F-150s 98-04, and I could go on all day on how bad they are built.

The 5.4L's have a ton of low end torque, peak torque is at 2500rpm, but there out of breath by 4000rpm.

 

we had an 03 Lincoln Navigator for a year with the 4 valve 5.4, seemed real sensitive off the line, then it sorta fell on its face, then seemed to come back to life up top.

might have been the tranny gears though.

The 2 valve 5.4 never really impressed me all that much. The 4.6 actually seemed peppier.