1997 Polo vibration

[Polo67]

Hi, i am new to the forum, i purchased a 1997 polo classic 1.4i which had had an engine swap to an 1.8i 8 valve motor.

My problem is a vibration that can be felt at idlem with my hand on the valve cover. As soon as i pull awau a strange chirping sound becomes very audible and the vibration gets worse until 2500 rpm then it disappears.

I have noted the front sway bar is touching the control arms, the engine mounts appear good, the engine does not move much when the car is revved.

I replaced distrivutor cap, rotor, HT leads and spark plugs which helped a bit.
Cleaned u[ earthing points and battery clamps.

Car is rather heavy on fuel in town, now about 7km/L , i do note Nr 1 plug is wet sooty but not oily, other 3 plugs all dark grey.

There is no petrol smell, i will be replacing fuel filter soon as well.

Anybody have any idea what might be causing this? Serpentine must be replaced as well as powersteering pump belt, could the timing belt be installed 180 degrees off?

The vibration is so that it makes pulling away difficult.