I finished the PI cam swap. The main purpose was actually to inspect and replace the chain guides, since I was getting some noise on the cold mornings. I decided that if I'm taking off the timing cover, I can throw on a set of PI cams while I'm in there. So I got a new set of take off PI cams for 35$ plus shipping (actually new, from a set of new PI heads which got aftermarket cams).
All I have to say, is that the 4.6 is a pain in the ass to work on! Taking the power steering pump off is mind numbing unless you want to open and purge the system (which I would rather not), and the gaskets for the valve covers are impossible to keep in place while trying to squeeze the valve covers in place. Totally, I spent around 15hrs doing the labor, but if I didn't want to pull the cover for the chain guides, it could have been much faster.
The guides weren't in bad shape. The tension side guides were maybe half worn, which isn't bad for 175k miles. I replaced those and bolted everything back together. I honestly don't notice much difference with the PI cams... the power change is very subtle. I think the torque band feels a bit broader, and it likes to rev a little more though. I doubt the 15hp claim, but it does seem to have a broader torque band.
All I have to say, is that the 4.6 is a pain in the ass to work on! Taking the power steering pump off is mind numbing unless you want to open and purge the system (which I would rather not), and the gaskets for the valve covers are impossible to keep in place while trying to squeeze the valve covers in place. Totally, I spent around 15hrs doing the labor, but if I didn't want to pull the cover for the chain guides, it could have been much faster.
The guides weren't in bad shape. The tension side guides were maybe half worn, which isn't bad for 175k miles. I replaced those and bolted everything back together. I honestly don't notice much difference with the PI cams... the power change is very subtle. I think the torque band feels a bit broader, and it likes to rev a little more though. I doubt the 15hp claim, but it does seem to have a broader torque band.