So, you want to buy and install Euro Ford Sierra Mk1 Lucas/Cibie headlights in your Merkur XR4Ti

Soon after buying my first XR4Ti (in the header picture of this blog), I noticed how good the European headlights looked on Ford Sierras, and, when properly fitted, how great they look on the XR4Ti. Here's an example found on the Internet. Based on this, I started my investigation into what it would take to obtain and install them.

First, the differences between XR4Ti and Sierra headlights

The Merkur XR4Ti had adequate headlights when this 30+ year old car was new, using classic incandescent bulbs with deep reflectors to throw light ahead of the car. The XR4Ti also had fairly useless, separate, inboard light pods that were turned on with the parking lights, serving as sort of daytime running lights, given that concept was just getting legs in the late 80s when these cars came out.

The XR4Ti's European cousin, the Ford Sierra, received large, one-piece headlight/driving light units, with glass faces. Not all Sierra headlights are created equal however, which I'll get to in a minute.

Second, what I learned from looking at two sets of Euro lights

There are two manufacturers of Ford Sierra headlights: Lucas and Cibie. 

I have one pair of Cibie housings that came already fitted on a car I bought, and I have one pair of Lucas housings that I bought separately, with the intention of installing them on my original XR4Ti. 

Here's what I think are the differences, based on looking at two separate sets of lights. 

Lucas:

• originally made for right hand drive (RHD) markets, namely the UK
• originally available in a wide range of Ford Sierras, from estates, saloons, and 3dr coupes
• has "city lights" provision, for a 194 blade-style bulb
• driving lights (inboard "high beams") were optional (if equipped, you'll see an twist opening on the top to allow for placing/replacing the H3 bulb)
• Plastic reflectors, for both driving lights and main lights
• Black, wide steel hold down clips for the front glass
• Uses H4 bulbs in the main lights
• Connectors allow for turning of each of the lights individually, where/when equipped

Cibie:

• originally made for left hand drive (LHD) markets, many European countries, and Argentina
• originally available in  Ford Sierras, also presumably for estates, saloons and 3dr coupes
• has "city lights" provision, for a 194 blade-style bulb
• driving lights (inboard "high beams"), takes a very small H3 bulb with one wire
• Metal reflectors, for both driving lights and main lights
• Bare, smaller steel hold down clips for the front glass
• Uses H4 bulbs in the main lights
• Connectors allow for turning each of the lights on individually; city lights, low and high beams on main bulb have their own trigger, driving lights

Common:

• Same lighting connector, although pins may be missing if no driving or city light options on the housing
• Same mounting, three bolts on the top, one bracket on the bottom
• Both Cibie and Lucas left-hand (driver's side in the US) main light reflectors have lost their chrome. I assume this was from sins of the past, cooking the reflectors with high wattage bulbs. Another reason to switch to LEDs. 

Third: Wiring for the XR4Ti, for LEDs

The XR4Ti has two relevant sets of wires on each side of the car, to run the forward-facing lights you use to drive.

1) headlights - XR4Ti uses a 3 wire socket to hold the main hi/lo bulb. Mine were yellow, white and brown (ground).

2) inboard "city"/DRL lights - XR4Ti uses a pair of wires for this, one grey/red (12v, on with parking lights), one brown (ground).

The XR4Ti wiring and headlight switch worked well enough for the stock lighting, with one high/low bulb. Average bulbs, average lighting for the 80s. They didn't plan, however, for this wiring and the headlight stalk to run more than one high wattage bulb, common in the Euro headlights. 

Euro lights = 55W low; H4 high 60/55W. (H83 Hella = 85W, off road only.)

XR = 9004, 65/45W. (9004 Off-road only, 100W/80).

Looking at the other articles (here and here), they were written 10-15 years ago. They all reference using power directly from the battery, and using the factory headlight wiring to run relays, allowing you to drive the most power directly to the lights. In 202x, we can benefit from low power, high brightness LED bulbs in every shape and form factor. 

So...you don’t need relays and extra wiring to run LEDs. If you still have the super helpful factory “convenience computer”, you may need to wire in resistors to keep the computer and the display happy. 

Euro Lamp Socket (TOP)

• City Lamp (18ga, grey) --> to have them turn on with parking lights, use factory b/grey (driver side), r/grey (passenger side) from smaller running lamp inboard of original headlamp. For the factory brown wire that runs with each, run the brown to a ground. This solved a dim light issue on my XR.
• High Beam (14ga, yellow) --> factory white
• Low Beam (14ga, white) --> factory yellow
• Driving Light (14ga, yellow) --> either, factory white, or separate switch
• Ground (16ga, brown) --> use factory brown ground wire

Other Headlight Options:

1987-1993 Ford Mustang housings are bolt-in replacements for the factory XR4Ti headlight housing, which retains the stock inboard running lights. 

Chevy Silverado (year?) housings have also been used.