It’s not raining at all where I am, unfortunately that’s about 110 miles away from my van1.6A multiplied by 13V will give that 20 watts number again and from experience will be around 2,000 lumen at 6500Kelvin so 4,000 lumen on dip in total.
Somewhere out there are going to be some H4 35 watt LEDs which should be a mid point in efficiency between lower halogen and higher efficiency HID lighting... who will post the first pictures?... cough... @andys ... cough, cough, it's only raining a little bit, yes I know it's dark too.
The pictures I posted were pretty blurry, I’ll try and take some better ones showing the cutoff etc