The other day, just for fun, I timed a 0-60 run in my 2003 Sebring LXi with the 200 HP 2.7 engine. It is supposed to do about 8.5 from several sources online, but I get 9.5-10. I don't think it has always been this way while I've had it.
Since, then I have changed the spark plugs with no improvement. The oil was just changed, and the air filter is fine. 2 or 3 months ago I had the waterpump and timing chains replaced. It may have started then but I have no real reason to believe that it has anything to do with that. While those were being replaced, I had them take the valvecovers off to look for sludge, as this engine is notorious, and they found little to none (they credit this to my religious 3,000 mile oil changes). I have not used any fuel system or engine cleaners such as SeaFoam.
Thoughts?