The dipped beams on my 04 plate astra have always seemed a bit dim, while the mains seem significantly brighter.
I've just had to replace one of the dips, confirming that it is a 55 watt H7. The other one is not significantly blackened. The lenses and reflectors look OK.
Presumably it is asking for trouble from fuses or switches to put in 100 watt bulbs, but is there anything simple which might make a significant difference?
I ran 100w H4's in my Focus for about 8 years with no problems.
It's likely that the lighting is fed via relays, so switches are not an issue; the wiring from the relay to the lamp might be marginal, as might the connector on the back of the headlight. Fuses are to protect wiring primarily, so are probably 15A minimum. This will easily carry the current of a single 100w lamp.
If you have the means to do so, check the voltage drop at the headlight terminal before and after trying the 100w bulb. If there is significant difference, either upgrade the wiring, or forget the idea.
Bear in mind if you decide to try it that to do so would make your car illegal.
Chris
it is worth checking that you are actually getting full voltage at the bulbs and that there is no significant restriction in the earth circuit.
With it running and the headlights on, check voltage at the battery, it should be around the 14 volts mark, then check what voltage you have between the headlight feed at the bulb and a good earth, it should be nearly as much as the at the battery, then check whether there is any voltage at the earth side of the bulb, there should be none or nearly so. If the voltage at the bulb is down then a relay will improve the lights, check by taking a heavy flylead straight from the battery positive to the bulb, if the bulb brightens you know you are on the right track. if the voltage is ok, but the earth is restricted then beef up the earth side of the bulb, (again you can use a flylead straight to battery earth to see if the lamp brightens), first find where the lead goes to the body and clean up or change the connection and / or replace the earth wire with a heavier one.
Thanks, good advice. Trouble is, space is all a bit tight round there. I was sort of assuming that earthing might be OK because the main beams are OK, but on reflection that's not necessarily true assuming each has its own relay. More playing needed!
Thanks, I will have a look at voltage drops.
on some cars the dip does not have a relay while main does ! if yours has one bulb each side then they share the same earth for main and dip each side. iirc h7 is a single bulb, so you may well have two different earth paths, one for each bulb.
They're SUPPOSED to. Duh!
First check you are actually getting full battery voltage at the headlamps. Even a small amount of voltage drop makes a big difference to brightness.
It's also worth getting good make replacement bulbs like Philips Vision - no name ones tend to be less efficient.
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