Very sluggish, hard to go above 65..suggestions?

[nwTercel]

I don't like to make these "spoon feed me" posts, but I am kind of stumped here. Recently I messed with my timing, adjusted it very slightly by sight and sound and I seemed to have lost power afterwards. I tried to move it back but knew it was off and had to go to work so off I go. I could barely keep it at 65 with a tailwind, then in a head wind and up slight grades 55-60 was a struggle. So today I got a timing light and adjusted it to factory spec, it seemed like it possibly fixed the issue when leaving my neighborhood, but as soon as I got to a stretch where I could do 50+ it was back to the sluggish and powerlessness as before. I checked vacuum lines, wires, stuff like that. Any suggestions what this could be?

[dlb]

did you disconnect and plug the vacuum advance hose that comes from manifold vacuum when you last set the timing?

[nwTercel]

You know what I did not, going out to the garage to do so now.

[Petros]

set your spark timing to 10 deg BTDC, rather than the factory 5 deg. it will improve your fuel economy and give a bit more power, but most importantly it will lower the exhaust temp and prevent the exhaust valves from getting over heated. the exhaust gases are cooler with more advanced timing since more of the fuel is burned before the exhaust valve opens, hence the better efficiency.

It does sound like you have a vacuum leak, likely from something you inadvertently disconnected.