Gcs

Hi, I am brand new to the forum. I recently purchased a completely stock 96 f150 xlt 4x4 supercab with 5.8 and 3.55 rear end. This truck has 105k and will be used to pull my vintage 5500 lb Airstream RV. It has tow package. I am wondering what modifications can be made to the engine to increase its low end "grunt". I know the engine is rated 325 ft of tourque at 2800 rpm. My goal is to either improve that torque or move it even lower. I do not care about hp or power in the upper rpm range but from idle to maybe 3000rpm. The truck is rated to tow 7100 lbs. I am just looking to make it more efficient and tractable in the lower rpm range. I know a cam change would do this and maybe I will wind up doing that but first I would like to try other tricks like exhaust, intake, timing etc. Thanks for any imput.

forrest411

Cam and long tube headers will achieve what your looking for. You can also try a spacer between the upper and lower intake. Not sure who makes them, but i know Ive seen them out there. What gear ratio are you currently running?

Gcs

Thanks, I would rather stay away from headers and rework the stock exhaust. I know the gains will be modest but anything to help. I realize cam change would be a big factor but for know I would like to just work with stock cam and see what I can get. Axle is 3.55 with 235x15 tires (stock).

Gcs

By the way I had a previous 96 with a 302 and tried a spacer and lost lowend torque and mpg

forrest411

Good luck. Not sure how much you can gain buy adjusting timing and throwing on a different muffler. The stock efi intake is a good for low end torque since that's what the motor was designed for.

sdmartin65

Unless you prefer some rumble, there is really not much to be gained by a muffler. I'd have the tune up items replaced and use top quality, brass contacts, decent wires and MC platinum plugs. The K&N intake will add about 10 hp. Replace the timing chain with an adjustable Cloyes and advance it the max. That would lower the the power band by about 300 rpm's and would be perfect with the 3.55 gears. At 100k the cam is probably retarded couple degrees from stretch so this will be a very noticeable mod. Stay with the stock tire size.

Gcs

Thanks, those sound like great ideas. I do have a high output coil that I bought for a bronco years ago and never used. Anything to be gained there? The idea I think is stonger spark and more complete burn of fuel.

Gcs

Also if I did go for the long tube headers and duels with an H pipe would that help or hurt low end.

sdmartin65

IMO finding an aftermarket higher voltage coil that compares to the quality of the oem can be difficult. I tried the high voltage coil and the end result was nothing but a headache.
Long or short headers are proven to give more power all around for the 5.8 but will cost more than you think. The O2 sensors are designed to sit a specific distance from the engine. Too far or close can hurt performance.
Installing a Comp Cam RV grind as the only mod you were to do would outperform all other mods combined. I can verify this from personal experience.

Gcs

Thanks the RV cam seems to be the way to go.