2005 F150 with 4.6 that I just finished replacing the timing chains/gears. Very slightly rough idle and rough acceleration up to around 1800 rpm. My scan tool says that the engine timing is 17 degrees at idle. Is this correct or did my timing chain jump a tooth during assembly? I can't find anything online about the proper initial timing for this engine. Thanks for any insight.

 

First question is did you use OEM Motorcraft parts or after market?
IIRC, at idle both cams should be at 0 advance.

These are interference type engines so if it is off time then your valves can be in danger of contact with the pistons.
If you have access to an advanced type of scan tool it can monitor cam timing in real time.

EDIT: Clarification on "IIRC, at idle both cams should be at 0 advance." Don't ask me why I was thinking of this a few weeks later. ADHD maybe?....
Your engines "base timing" is probably in the 15deg range but the cam phasers should be at 0 advance at idle.