sorry for the long post, but i feel it's helpful if i give as much 411 as possible before posing a question:

this is what i have done to my sorta new to me 1994 f150 4x4 351 e4OD 185000 miles. when i got it i felt that there was very little power for a 351. i drive a 1991 3sp 302 2x4 as a work truck, and granted, it is a different truck altogether, but the work truck had much more pickup than my pickup.

-rear drive shaft u-joint (it was vibrating on the highway, took care of it)
-tranny flush/fill, filter and pan gasket (emptied torque converter)
-engine oil/ filter change
-coolant flush/fill (did not do the engine plugs, just the lower rad hose and drain ****, actually flushed the system a total of 10 times), refilled with 50/50 mix
-new generic spark plugs (gapped .044, per the haynes manual), wires, dist. cap and rotor (all napa brand), original coil
-compression test, all results (engine up to temp) within 185-200 psi range
-base timing (with SPOUT connector unplugged) set at 10 deg BTDC (was at 10 deg after TDC)

i feel like the truck runs a ton better, but was wondering if anyone can suggest other tests, or the like, as i want to take this truck and pull a 5000 lb trailer to the southern tip of baja ca, 3000 miles round trip, with a few passes to climb. i'm looking for best fuel mileage i can get, and as much power from this truck too. i probably can budget another $500 towards this.

-what do you think about upgrading the ignition system, or even just sidegapping the plugs?
-i don't have to pass smog for another 2 years, will removing the cat (s) make a difference?
-any other suggestions? i have 31x10.5 tires on it now, the stock size is 265 75 R15, gearing is 3.55.

thanks so much, really looking forward to your responses, mike

 

the double post. blech.

 

that spark plug gap doesnt sound right. my truck is a 5.0 and the sticker on the underside of the hood says its supposed to be .052-.056

i cant see why a bigger v8 would have a smaller gap

 

interesting. i read about the "sticker under the hood", but can't find mine. well i do have one, but its a reminder to remove the SPOUT plug before setting base timing to 10 BTDC.
does anyone know for sure if the 351 takes a similarly gapped spark plug?

 

The 351 and 300 both have smaller gaps than the 302. Don't know why but that's the way it is.

 

why does that sound wrong to me

 

Because its a bigger engine. You'd figure the 300 and 302 would have the smaller gaps. I thought the same thing. I looked it up and sure enough I found the 302 had the bigger gap.

 

Since it sounds like your engine is in good condition, I would do the "6 liter tune up" http://fullsizebronco.com/forum/showthread.php?t=63592 and would also side gap your plugs http://performanceunlimited.com/docu...degapping.html. You could also index the plugs if you want to spend the time to do it http://www.bullittarchive.com/5005.htm. For the timing bump, a few members that I know of have theirs set at 16 degrees with no issues.

 

Seafoam. Seafoam. Seafoam. And about that trailer. I feel sorry for your truck. Thats going to be a load. Especially 3000 miles.

 

i love and have had wonderful results with seafoam. i run it only in my gas tank though. i ran it in my oil once and i felt like it thinned it out quite a bit. i actually changed my oil early because of it. but in the gas tank, i notice an increase in mpg. i just ran a can through my wifes ford escape and it eliminated the surging and stutter it had with in the first 20 miles.

i would also suggest a high grade oil for the trip. personally i would run royal purple a little thicker than you normally. i.e. if you normally run 10-30, i'd run 10-40. especially going in the heat like that. Good luck!!