Headlights

[Aleksandar]

What's the difference between 3 types of headlights on the e30, the smiley, the dot and the earliest Hella one?

[Brianmoooore]

The earliest dipped (outer) headlamp was a conventional parabolic reflector type like the main beams.
These were replaced on facelift cars by a projector type lamp (years ahead of most of the opposition) which used a convex glass lens to focus the light, with a metal shield to control the beam pattern. I presume this is what you man by 'dot', unless you mean the US approval system.
After a short time, a cut out was made in the 'reflector' of the facelift lamp, to allow some light, directly from the bulb, to illuminate the road near to the car.
This type was known as the smiley, for obvious reasons.
The reflector in the facelift type does nothing at all, except act as a reflector for the parking light bulb.
.

[Aleksandar]

Thanks, cheers.

[green-blood]

quick addition

the "dot" and smiley are plug and play, you can just swap them in/out

however the pre-facelift lights have different connections. you will need to do some wiring to splice in later lights