I tow a 28' Airstream with my 1998 Navigator, 5.4 2v. I am thinking of supercharging it. Does anyone have experience with this. Also, I am considering buying a 2003 Navigator with the 32v engine, as a possible supercharging candidate instead. Thanks, Ron

 

Kenne Bell has a nice kit for the 98-02. I have the 32v and my kit works nicely. I thought the 03's had the 3v?

 

Who is Kenne Bell? The 2003 Navigator has the 4v. The 2005 got the 3v. Thanks, Ron

 

I have a 98 Expedition with the same motor with all the mods listed below and it is great for towing.

 

What's the weight of the trailer? The 2V 5.4L is lethargic due to the spark constraints it has. The 4V 5.4L is a much better towing engine-it can tolerate alot more spark advance due to intake and cobustion chamber design. I tow a 6500lb gross weight 30 ft travel trailer with my '01 Navi,and it does the job quite well with minimal fuss. I think a swap to the 32V engine would get you what you're looking for vs the expense of a S/C.
JL

 

I have modified the Navigator engine with a Superchips program, which adds allot of advance, I believe. Also, installed is a free flowing Gibson muffler. These mods added allot of snap. I wouldn't consider swapping engines. If I stay with an unsupercharged 4v, I'll buy a 2003 Navigator, which has many desired improvements. Ron

 

I guarantee you it's not adding alot of timing advance-the 2V's will simply not tolerate much more than stock-even with premium fuel. On my personal truck and the company truck,both have to run LESS than OE timing to get them to run on 87 octane without pinging. Supercharging the 2V 5.4L that's lacking the proper supporting internal engine components is like a ticking timebomb...especially if you're towing.All it takes is one time for it to ping,and it's all over.
JL

 

With the prices on used 2006's right now - I wouldnt consider an 03. There are used 06's selling for $34-37K. An 03 is gunna run you $22-25K.

The 06 gets you a slick 6-speed tranny, better fit and finish, the 3V engine (not really better than the 4V, but more supported by the aftermarket due to the F-150 crowd)

I have an 03 BTW so I'm not biased to the 06.

 

upgrade to an 03 or newer imo.

 

Is the 2003 Expedition a 4v? If so, how did you fit the Harley supercharger?

 

nope, its a 2v. the expys didnt get the 3v until 05, and never had a 4v(stock).

 

I tow a toy hauler about 7000-7500LBS with my 03 FX4 5.4 (2V)...It does fine on the flats and stop and go's but I feel the need for a little more on hills maybe only a 4-5 LB Boost would be perfect...So I would supercharge as I hope to soon..With a low boost your interanal parts will be fine.....

 

I hear people brag about that all the time..then not long after I get a call about where to find a forged shoftblock. It's fine until you get one tank of low quality fuel,or you get in a situation where you get even the slightest of spark knock. All it takes is one time with these crappy pistons,and it's done.
JL

 

www.kennebell.net

 

I've got 135K miles on my Procharged 5.4 (35K of those miles with the supercharger).
10.5 psi peak boost, but less at lower RPM.
I tow a 7,000 lb boat thru the desert, it handles it very well.

If you want to supercharge it, make sure that your engine is in good shape (compression or leakdown test). Also, make sure you've got a good tune, you don't want the possibility of detonation while towing.