Runs like ##?% @ idle

[porschetub]

My 2.7 powered 85 has a really rough idle something like an over cammed V8 racecar.
I had some vacuum leaks that I've since repaired and this cured the high idle problem,before that any adjustment on the AFM and throttle body had little or no effect on idle speed,it now idles at correct RPM.
The car runs smooth from cold until the cold start enrichment switches off,it also backfires through the aircleaner until the engine has warmed up.
The noise @ the tailpipe sounds like a 3 cyl car and on the road the car feels a bit down on power.
Have checked/replaced the following;
AFM- cleaned out main body and contact board
Spark plugs- fitted new ones.
Replaced cracked rotor.
Checked for loose inlet manifold
I'am starting to feel hatred for my little black car -PLEASE can someone help

[porschetub]

Changed injectors and fuelrail(it started to leak),car has more power and idle has improved somewhat but I didn't check the inlet manifold properly found one very loose bolt,I think a reseal is in order.
Can anyone tell me if the 2.7 injectors have a higher flow rate than for the 2.5?,thanks