4.6L to 5.4L swap.....tuning help.....?

[slickum01]

Looking for advise and ways to move forward on my project....

I have a 99 ford expedition all time 4x4, 4.6L and have completed a 5.4L PI motor swap into the vehicle. Im using all of the factory 4.6L electronics/wiring/mass air. It is equipped with accel coil packs and retained the original 4.6L torque converter and transmission. I kept the factory exhaust with the addition of shorty headers and have cold air intake to add on. It is up running and driving.

Im looking for tuning for the vehicle to compensate for the larger displacement, gas milage and any possible shifting combinations/issues that may be encountered by using the 4.6l converter/trans with the 5.4L?

Im not looking to change the equipment or modify it later down the road. Any suggestions locally or easy chip to deal with over the web.....?

Thanks for the help!

[shumpertdavid]

Might help if you told us were you were located, Andy with Prime Tuning if you're in the Ft Worth area. Tuning will likely be pretty close as is, the transmission should function just fine as well.

[slickum01]

North Ft Worth, speedway area......... This was posted on one of the boards but there seams to be a lot of debate of what real problems there are using the 4.6 equipment on the 5.4....;

Transmissions: the 4.6 and 5.4 have the same bellhousing bolt pattern. That means that all the transmissions will bolt up. All the 5.4 engines have 8 bolt crankshafts. Some 4.6 engines (ROMEO ENGINE) have 6 bolt cranks. You will need the flex plate from the 5.4.
Manual transmissions: If you don’t have an 8 bolt flywheel a flywheel from a 1997-8 4.6 Windsor engine will work. As it has 8 bolts it will bolt right up to the 5.4 crank. Remove the flex plate spacer and install a pilot bearing from a 4.6.

Special note about the different automatic transmissions and their respective harnesses. You cannot run a 4R100 transmission with a PCM that had a 4R70W transmission and vice versa. The transmission harnesses are different and will not plug into the different engine bay harness. The control functions in the PCM are not compatible so the transmission will not function properly.


Torque Converters:
4R70W
ENGINE............Stall Speed............Multiplication
4.2..................1978-2330...............2.3:1
4.6..................2105-2505...............2.3:1
5.4..................1830-2190...............1.9:1

4R100
All Engines......??????....................2.2:1


If you swap a 5.4 into a 4.6 engine bay and use the 4.6 converter you will multiply the 5.4's torque at a higher rate and at a higher stall speed which will put the torque at the transmission input shaft close to the limit if not over the limit of the 4R70W. The 99+ 5.4 produces 350 ft/lbs of torque. 90% of that is available at 2000 rpm. The stall speed of the 4.6 is above the 2000 rpm range so more than 90% is available. 350 ft/lbs x 2.3(4.6 multiplier) x 90% is 724.5 ft/lbs.

>>> LINK TO POST

There are a lot of post I find that say they have no problems also.....