Hi there. New to the forum
I'm about to do a rebuild on a donor motor for my 1998 f150 4.6l. I am looking to upgrade at the same time but don't know where the best way to spend my money would be. Or if it's even worth it to add hp to these motors, or should I go the safe route and bring back to stock... I don't want to switch to the 5.4 because I got the donor for free and have read up on the difficultys with marrying the exhaust and sensors.... trying to get the most bang for my buck. Any ino would help. Thanks

 

If you want more power, put a set of PI heads on it. You will need a truck PI intake and exhaust manifolds. This is assuming the donor is non-PI, exactly what is it out of?

 

It's out of a 1998 f150 4x4 auto. It's going into a 1998 f150 4x4 5 speed.

 

That's non-PI. The truck 4.6 didn't get PI till sometime in 2001 if I remember correctly.

If you don't want to chase down a set of heads and manifolds, just rebuild it stock. Note that you will have to replace the flexplate with your flywheel (assuming they are both Romeos or both Windsors).

You can't increase the power very much with a 5 speed, the transmission is light duty and won't last under much more than stock power.