Ron Slott's Tech-Tips
This is where I pass on some of my hard earned experience to those of you who are preparing your car for club motorsport, maybe for the first time. Hopefully this info can help you to overcome some of those initial hurdles, which can be both expensive and embarrassing.
Top Tip One - Wiring up Spot lights.
Top Tip One - Wiring up Spot lights.
Road Rally Spotlamps – how to wire em up.
The first thing to ascertain, is how many auxilliary lamps (if any), can be fitted. The MSA 'Blue Book' states 'No more that 4 forward facing beams'. It is referring to how many lights can be switched on at any one time. If your car has 'twin headlights', then it is unlikely that you will be able to fit auxilliarys. However, all is not necessarily lost. As in the case of the MG ZR, it has ONE big lamp each side, the 'twin' effect given by the shape of the nose cone. Added to that the fact that dipped beam is in the outer element, and goes out when main beam is activated. Auxilliary lamps then are allowed.
The next thing to get clear in your mind, is how they should work. The 'Blue Book' is quite clear in that they MUST go out when headlights are dipped. However, when you consider that in a quiet zone you must extinguish ALL auxilliary lights, dipping becomes undesireable. Main beam here is a considerable asset. How your spots are wired then is crucial.
You should never introduce a new circuit to your car without the safeguard of a fuse, as a short on a non fused circuit will always result in a fire. Furthermore, to make your lights operate as described above, you will need a few more parts.
You will need at least the following:
1 x relay.
1 x illuminated switch.
1 x Auxilliary fuse
Approx 3 metres 2mm dia cable.
Approx 3 metres 5mm dia cable.
Approx 1 metre 5mm dia Earth cable.
All necessary connectors, screws and fittings as required.
Firstly, affix your lamps in an appropriate position (Ideally between the headlights and spaced as far apart as possible). Modern cars, particularly those with plastic and composite nose cones do not usually allow for this, so you may have to invest in some purpose made mounts, or visit your local blacksmith and have some specially fashioned. Either way, there's nothing more irritating to a Rally Driver than wobbly lights at night.
The first thing to ascertain, is how many auxilliary lamps (if any), can be fitted. The MSA 'Blue Book' states 'No more that 4 forward facing beams'. It is referring to how many lights can be switched on at any one time. If your car has 'twin headlights', then it is unlikely that you will be able to fit auxilliarys. However, all is not necessarily lost. As in the case of the MG ZR, it has ONE big lamp each side, the 'twin' effect given by the shape of the nose cone. Added to that the fact that dipped beam is in the outer element, and goes out when main beam is activated. Auxilliary lamps then are allowed.
The next thing to get clear in your mind, is how they should work. The 'Blue Book' is quite clear in that they MUST go out when headlights are dipped. However, when you consider that in a quiet zone you must extinguish ALL auxilliary lights, dipping becomes undesireable. Main beam here is a considerable asset. How your spots are wired then is crucial.
You should never introduce a new circuit to your car without the safeguard of a fuse, as a short on a non fused circuit will always result in a fire. Furthermore, to make your lights operate as described above, you will need a few more parts.
You will need at least the following:
1 x relay.
1 x illuminated switch.
1 x Auxilliary fuse
Approx 3 metres 2mm dia cable.
Approx 3 metres 5mm dia cable.
Approx 1 metre 5mm dia Earth cable.
All necessary connectors, screws and fittings as required.
Firstly, affix your lamps in an appropriate position (Ideally between the headlights and spaced as far apart as possible). Modern cars, particularly those with plastic and composite nose cones do not usually allow for this, so you may have to invest in some purpose made mounts, or visit your local blacksmith and have some specially fashioned. Either way, there's nothing more irritating to a Rally Driver than wobbly lights at night.
Next ensure that both lamps are properly 'grounded' or 'earthed', using HD 5mm cable (After all, all the power going in, has to get out, a bit like plumbing). Very often this is done directly from the bulb, but grounding the shell where metal cases are used is always a good idea too.
Next decide where to locate all your parts and cable runs etc. Note: keep cable runs as short as practically possible, and place all parts where they can be easily accessed. Ideally, the relay and fuse box should be adjacent to the battery to minimise the length of the lamps 'power lines'.
Next decide where to locate all your parts and cable runs etc. Note: keep cable runs as short as practically possible, and place all parts where they can be easily accessed. Ideally, the relay and fuse box should be adjacent to the battery to minimise the length of the lamps 'power lines'.
Think of the relay as two circuits. One switching the other, and all this should be clear. Locate a feed from the 'Main Beam' side of the headlamps, and connect one 2mm wire into it. Connect another 2mm wire to one of the 'coil' sides of the relay. Run these two wires together, through the bulkhead to the illuminated switch you have fitted to the dash. Don't forget to fit a suitable grommet and seal the hole properly where it passes through any metal panels. Using suitable connectors, wire into the switch (Note the earthing requirements of the switch. Likely to enable the light in the switch to work). Now turn your attention back to the relay. Connect the other side of the 'coil' to earth/ground.
Now is time to look at the 'Power' side. Connect a 5mm cable directly from the battery to one of the fuses in your new fuse box (Note, you will need at least a 15amp fuse to power two 55W lights). Next connect the other side of the fuse, again using 5mm cable to the switch side of the relay. Then connect the 'switched' side of the relay to your lights, again using 5mm HD cable (Note: a handy hint here is to fit detachable connectors near the lamps, maybe even fitted to the vehicle body. This enables simplified and rapid removal of the lights should you be doing a Targa Rally or similar).
A thorough check and recap is advised now, just to minimise any mistakes. Then switch on the side lights, then dipped beam, then main beam, and finally, flick the spot light switch and grin widely as they come on for the first time. Dip the headlights and ensure the spots go out. Ensure that the illuminated switch shines when necessary ........ and you're ready to roll (Pun fully intended as the new visible range encourages you to go much faster than previously).
All that's left to do now is to set up your beams. Different drivers have different preferences, but the most popular are either, both dead ahead (my choice as it gets all the light in front of me), or crossed at approx 25 yards so that the left lamp is pointing to the right of centre, and the right is pointing similarly to the left (Giving better coverage of the road ahead whilst sideways or cornering). I find that it is best to do this 'setting up' at night (in the dark) against a large flat wall/fence or similar, where you can see where each beam points as you move it. Choice is yours. Either way, badly installed spot lights are often more of a hindrance than a help.
Stay tuned for the next Tech-Tip!
Now is time to look at the 'Power' side. Connect a 5mm cable directly from the battery to one of the fuses in your new fuse box (Note, you will need at least a 15amp fuse to power two 55W lights). Next connect the other side of the fuse, again using 5mm cable to the switch side of the relay. Then connect the 'switched' side of the relay to your lights, again using 5mm HD cable (Note: a handy hint here is to fit detachable connectors near the lamps, maybe even fitted to the vehicle body. This enables simplified and rapid removal of the lights should you be doing a Targa Rally or similar).
A thorough check and recap is advised now, just to minimise any mistakes. Then switch on the side lights, then dipped beam, then main beam, and finally, flick the spot light switch and grin widely as they come on for the first time. Dip the headlights and ensure the spots go out. Ensure that the illuminated switch shines when necessary ........ and you're ready to roll (Pun fully intended as the new visible range encourages you to go much faster than previously).
All that's left to do now is to set up your beams. Different drivers have different preferences, but the most popular are either, both dead ahead (my choice as it gets all the light in front of me), or crossed at approx 25 yards so that the left lamp is pointing to the right of centre, and the right is pointing similarly to the left (Giving better coverage of the road ahead whilst sideways or cornering). I find that it is best to do this 'setting up' at night (in the dark) against a large flat wall/fence or similar, where you can see where each beam points as you move it. Choice is yours. Either way, badly installed spot lights are often more of a hindrance than a help.
Stay tuned for the next Tech-Tip!
