Checking in from Kansas

[the_law_man01]

I bought a 1997 XLT with 4.6L last December. Drive it to the Rocky Mountain region last summer. Absolutely gutless on the highway, but in 4x4 Low she climbed to the top of a couple mountains without a problem. She's had the dreaded exhaust leak since before I bought it. May have burned some valves. Compression seems to be getting worse. Rear main seal is leaking, head gasket oil leak to the exterior on left side. But, she starts every time, every day.

Considering swapping to another 4.6L if I can, and from the little bit of reading I've done so far, I'm wondering if I can swap in a PI engine without any issues. It sounds like that's my best power gain option. I don't know. I'm just now learning about the 4.6L line.

Regards.

 

[GlennSullivan]

Hello and welcome. I've never owned a 4.6 Expedition, but did have 2000 5.4 2 Valve Expy, and have been involved in the Mustang hobby for about 25 years, so pretty familiar with Ford Modular engines.

The 4.6 PI motor did have more power and additional TQ over the original 4.6 2 valve. Putting PI heads and intake on a 4.6 would give you 260HP and 302TQ. Whereas the 5.4 2 valve was 260HP and 345TQ. When pulling around the weight of the Expy, TQ is important. My 2000 5.4 2 valve was OK on regular highway driving, but get in the mountains or try to pull a trailer and it was a DOG.

If you were going to swap an engine, I would look into what it would take to put the 5.4 Expy engine in. Would give you move HP and TQ

If it were financially possibly, I would sell the 97 and pickup a newer 2008 - 2014 5.4 3 valve, providing 310HP and 365TQ.