Quote:
I won't definitively say ALL, but most square headlights made for the Dolomite and Toledo range (also Allegro, Hillman Avenger et al) are made to accomodate the 410 tungsten bulb, rather than the H4 Halogen (AKA 472) There ARE Halogen conversion bulbs available, I have them in the Carledo, but can't remember their number at this time of night and the garage is dark and cluttered, I'll check tomorrow!
These bulbs are the same 65/55w output as the stock H4 (the 410 is a measly 45/40w) and have not, in the 10 years i've been running them, given any trouble to my dipswitch and wiring.
The real killer on the 4 lamp cars is having 4 main beams (at least 260w) going at once, a problem the 2 lamp cars don't have. Relays, if you do decide on belt and braces, would be wired exactly the same as the 4 lamp cars, diagrams are elsewhere on these pages.
If you intend to fit a couple of long range driving lights to supplement the main beams, i'd recommend relays for the same reason as on the 4 lamp cars.
Steve
As Steve has said, the normal substitute H4 quartz-halogen bulb (P45t mounting flange like the factory-fitted 410 45/40W glass-envelope bulb) is 60/55W, but one might still be able to get P45t flanged, 100/80W quartz-halogen bulbs, like those fitted to my 1973 VW Type 2.
From as early as the mid-1970s, quartz-halogen, 60/55W, H4 bulbs, with P45t mounting flanges, have been available to substitute, into the ordinary non-H4 headlamp units, as I did in 1976, with my British specification, 1973 VW Type 2; resulting in vastly improved headlamp performance, on both main & dipped beams.
In 1989, I learned of 100/55W & 100/80W, P45t flanged H4 bulbs, of which I used the latter to further upgrade my headlamps; also upgrading the circuit with heavy-duty cable and two Hella 40A relays (one each, for main & dipped beams).
These P45t flanged H4 bulbs, have been known to be available in 60/55W, 100/55W, 100/80W & 130/90W power ratings.
One can also obtain P45t to P43t adapters, which enable one to fit the more commonly available, standard & uprated P43t flanged quartz-halogen into headlamps designed for P45t flanged bulbs like the 410.
The P43t flanged H4 bulbs, have been known to be available in 60/55W, 100/55W, 100/80W, 130/90W & 160/100W power ratings.
_________________
Regards.
Nigel A. Skeet
Independent tutor of mathematics, physics, technology & engineering, for secondary, tertiary, further & higher education.
https://www.linkedin.com/profile/view?id=308177758
Upgraded 1974 Triumph Toledo 1300 (Toledo / Dolomite HL / Sprint hybrid)
Onetime member + magazine editor & technical editor of Volkswagen Type 2 Owners' Club