Ian Anderson

Lifetime Supporter
Compared to modern cars the lights are "useless"

Sort of makes me wonder about the sanity of the drivers doing 200mph at night!

Best improvement I have seen is to fit HID bulbs and units



The bad news, I looked at HID and LED options and there are clearance problems on my early CAV mono to the back of the fender liner. And with HID it would also require a rewire kit with ballast.
The good news, I replaced the halogen bulb that was in the car for 15 years and noticed the output significantly better. Apparently the bulbs age over time and as my wife reminds me regularly, "many things dim with age...".

When the technology develops a bit more and the cooling assembly gets a bit smaller, I'll probably go to LEDs for the simplicity.

While not a big change, here's the car with one side sporting the fresh halogen and the other the old one.


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Neville, good to see/hear you're still about and caring for your 40. Just so you know you're not alone, I found the headlights to be as Ian stated....useless on mine also. Pat's suggestion(s) are always worth looking into. Good Luck. Give me a ring sometime so we can catch up.

Ian Clark

Hi Neville, might be worth checking the voltage at the headlights when on, low beam then high beam. You're looking for 12 volts ignition on or 14 volts with engine running.

The early CAV cars ran the headlight power through the ignition switch to the light switch to the headlights passing through the molex connectors along the way. Lots of opportunity for voltage drop. Also the ground wire were quite light. So I wouldn't blame the lights right away.

If the voltage is down you can put a relay up front in the rad cradle, control the relay with the headlight switch and feed the relay directly off the master battery disconnect switch with a heavy gage wire. Run the relay output to the lights. Also a separate ground lead to the lights that is screwed to the chassis will allow max power to flow to the lights.

The ignition switch bypass relay for headlights has been done to most CAVs, that saves ignition switch failures but not low voltage at the lamps.

No matter what kind of lights you end up with the voltage must be in the 14v range to work properly so it's worth making sure of what you have.

This is a timely posting!! I just switched to LED lights in my CAV. They managed to fit inside the existing inside lining and plugged straight into the current wiring. The only thing extra I needed was some little plastic conversion adapter rings to convert from P45T to P43T fittings (that took a little bit of searching to find what I needed!).

The difference (forgive the pun), is night and day! I very nearly hit a wild black pig. This prompted me to look into the change. 70mph and ~70ft before seeing a wild pig gives very very little time to react.

Anyway, the change was very simple, very effective and cost less than $100. I am going to dig out the links for people and a couple of pictures, although the pictures really don't do the change justice.

Another really nice side note is that the current draw is less. I also have LED bulbs on order for the back. They should be here next week.

Ian Clark

Talk about a problem solver! thanks Karl. The LEDs have a big advantage in lower current draw. Thanks again Cheers
OK, I have also switched the rear bulbs to LEDs. Again, a big improvement! Here are the bulbs I bought off of Amazon:

JDM ASTAR Super Bright 78-EX Chipsets 1156 1141 1073 7506 LED Bulbs with Projector,Brilliant Red https://www.amazon.com/dp/B01J2KKMHE/ref=cm_sw_r_cp_apa_63cFybHNKMY6M

JDM ASTAR Super Bright 78-EX Chipsets 1156 1141 1073 7506 LED Bulbs with Projector,Yellow https://www.amazon.com/dp/B01J2JM7BE/ref=cm_sw_r_cp_apa_DmdFybMZNGEJ2

I went with colored LEDs, much better than relying on the color of the lenses with brighter bulbs.

I hope this is useful for someone.




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They plugged straight in with no resistors. I did go with the same bulb for the break light and rear light. Although the existing brake light is as big as the indicator and bigger than the rear light. My thinking was that the two red LEDs will essentially combine to give more light when breaking. It really looks like a modern lighting setup now, especially with the front headlights too. Avoid going for white LEDs for the rear. I bought some and put them in thinking that the lens color would take care of it. Instead it overpowered the lens color. Those were also too weak. I found the ones I linked to Amazon work perfect.
And the front LEDs fit within the space available without any changes to the cover in the wheel well. I am very happy with the outcome, especially given how little work it took!