Anyone used 80/100 watt H4 Headlights on a Volvo?

[simon hewitt]

Hi All,
Just a quick question, the other day I had a headlight fail on my 1997 V40 No problem, had a spare to put in but went to get some better light output bulbs as the last ones were philips vision plus bulbs which are great, however the auto factor where I go to sold me some 80 watt / 100 watt H4 bulbs, he says they are ok on standard wiring, and legal for use in the uk? have not tried them, just the thought of 80 watts per bulb when day lights are on continuos makes me wonder what will happen in time, any idea's

Thanks in advance

Simon

1997 V40 1.8i
99,000 miles
Just run in.

 

[James Sweet]

Hi All,
Just a quick question, the other day I had a headlight fail on my 1997 V40 No problem, had a spare to put in but went to get some better light output bulbs as the last ones were philips vision plus bulbs which are great, however the auto factor where I go to sold me some 80 watt / 100 watt H4 bulbs, he says they are ok on standard wiring, and legal for use in the uk? have not tried them, just the thought of 80 watts per bulb when day lights are on continuos makes me wonder what will happen in time, any idea's

Thanks in advance

Simon

1997 V40 1.8i
99,000 miles
Just run in.

The lamps should work well if they're quality bulbs, however don't get cheap ones. I wouldn't run such big bulbs on stock wiring though, even before I went to high powered bulbs, a wiring upgrade made a very noticeable difference.

 

[Rob Guenther]

How exactly do you rewire a car's headlamp to better wiring? The wires seem to go into the connector that clips into the bulb base (which appears not to be designed for seperation and resolderage of new wires), and then they go off into this mysterious realm of somewhere i can't see; into the oily area of the engine, then in thru a hole in the firewall, which appears to be sealed with something.... most likely to a wiring harness near the lightswitch, I would imagine.

 

[James Sweet]

How exactly do you rewire a car's headlamp to better wiring? The wires seem to go into the connector that clips into the bulb base (which appears not to be designed for seperation and resolderage of new wires), and then they go off into this mysterious realm of somewhere i can't see; into the oily area of the engine, then in thru a hole in the firewall, which appears to be sealed with something.... most likely to a wiring harness near the lightswitch, I would imagine.

Well there's more than one way to do it I'm sure, but here's what I did. First get a pair of quality relays, ideally the type with two output pins that both switch on at the same time, I used K-Jet power relays I got from a junkyard, but I think 700 series foglamp relays are the same. Next I got a pair of waterproof inline fuse holders at Schucks and wired them directly to the alternator. From those use heavy wire to the common pins of the two relays. This gives you two separate circuits, one for high beams and one for low beams. From the output pins of the relays run wires to the headlamps, if your factory sockets are heavy enough you can snip them off and splice them in, or you can get heavier aftermarket sockets. I grounded the lights to the ground block nearby them on each side. Now you need to snip the stock headlamp connectors off, and since the bulb failure sensor (in the older cars anyway) measures the difference between the two sides, I tied both together and ran the wires to the relay coils. This defeats the bulb failure sensor for the headlights (you can tell easily if a headlight is out) but retains it's function for the rear lamps where it's really handy. Anywhere I had to make a splice I used heatshrinkable butt connectors and took care to neatly crimp all other connectors. All wiring was bundled inside sheathing and neatly tucked away and the relays mounted to a small bracket I fabricated from a scrap of aluminum, unless they were well familiar with these cars, no one would even notice anything was modified.

 

[Rob Guenther]

Hmm... sounds like more of a summer project, not for right now when it's anywhere from 0 to -30°C outside...

And this type of mod can work on any car I would imagine? And will it show improvements on cars with already good lighting (ie, my 1999.5 Golf?... i'd rather do it on my parents' 960, which I find has lacklustre lighting for something touted as such a safe car (the only time I drive it is at night, tho not as often as I used to)... I guess it was as good as it could get in 1993 or something... is there any way of running the highbeam with the lowbeam? This is how it seems to be done on cars with separate bulbs, it gives you 110W instead of the usual 65W. But i'm thinking it could overheat the bulb...

 

[Spanky]

This defeats the bulb failure
sensor for the headlights (you can tell easily if a headlight is out) but retains it's function for the rear lamps where it's really handy.

I thought the headlight failure feature was useless too until it really helped me out. I was running some errands Thanksgiving morning and the headlight failure light came on. I just happened to be driving by an auto parts store so I pulled over, verified that a headlight was really out, bought a replacement bulb, popped it in right there in the parking lot (remember it was daylight) and finished my errands. That night I was driving the 100 miles home from Thanksgiving dinner with my wife's family in the rain on dark rural roads. My belly was full and I was immensely content as I realized I would be driving on these dark, curvy rainy roads with only half the usual light if it were not for the headlight failure sensor.

I find it a very useful feature.

 

[John Roden]

Fow what it's worth, I bought some round 100w Hella lights that bolt on the bumper and a kit that included relay and wiring. I had an independent garage do the install on my Astro van (it was cold last winter too..) and I have to say I just love them, especially during deer season.

 

[James Sweet]

I thought the headlight failure feature was useless too until it really helped me out. I was running some errands Thanksgiving morning and the headlight failure light came on. I just happened to be driving by an auto parts store so I pulled over, verified that a headlight was really out, bought a replacement bulb, popped it in right there in the parking lot (remember it was daylight) and finished my errands. That night I was driving the 100 miles home from Thanksgiving dinner with my wife's family in the rain on dark rural roads. My belly was full and I was immensely content as I realized I would be driving on these dark, curvy rainy roads with only half the usual light if it were not for the headlight failure sensor.

I find it a very useful feature.

There's no easy way to utilize it and run relays though, at least not that I've found. I keep a little baggie of spare bulbs in the trunk of both my cars, a headlight bulb, some marker lamps, a couple brakelight bulbs, then if one burns out I simply pull over and put in a spare.

If you have the european lights and hook up the daytime running lights there's no reason to drive in the day with your headlights on anyway.

 

[Rob Guenther]

Those are nice, but we don't drive up North very much... so no real need, we are near Toronto, and I don't want to be one of those assholes who drives with their fog lights constantly running. (yes I realize I could turn them off when not needed.... but then i'd never get to turn them on ).

 

[John Roden]

That's what the relay does, it just sparks up the big hellas when the high beams are on, so you don't need to even think about it.