Rough idle and rough in high rpms

[Tread]

Ok, I'm new (a few months) and I have an 88 LX Sedan 235,000. I had the valves
adjusted this spring, (it had compression on TWO cylinders!) it ran great at high rpms before and after. But recently it's been running really rough passed 5000rpm and starts losing power at 4 grand. Correct me if I'm wrong, most engines make MORE power the faster they spin! Like I stated before, I need to adjust the valves again.

Another thing, how much does the MPG's drop when going full de'vac?
Is there a way to advance the secondary so it engages sooner? (I don't think it's working at all):ugh:

Anyway, Thanks in advance for any help on this!

[POS carb]

if it ran "great" on two cylinders and worse after the valve job I think your mechanic screwed up.

the secondary won't open if you are reving it in neutral/park. It opens when it needs to under load.

[Buzo]

....
Another thing, how much does the MPG's drop when going full de'vac?
...

My car dropped from 24 MPG to 17 MPG.

[Dr_Snooz]

If you were running with valves adjusted so badly that two cylinders weren't compressing, you are looking at a head rebuild at the very least.

[Tread]

When I said It ran great with two cylinders I ment it ran smoothly, not well. I feels like it's loosing power at 4500 rpm... Vacuum leak? I've noticed that if I punch it, The accelerator pump richens the mixture for a moment then it looses power. Is there a way to enrich secondary?