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Halogen Tail Lights
Posted: Sat Jan 10, 2004 10:05 am
by Gareth
Hi all. Could do with some advice.
After a nasty Rover assaulted Phyllis, I've been thinking about uprating the lights at the back of the car. These were not at fault, but they aren't quite as bright as other cars, now are they?
The club mag is running a readers tech tip about halogen rear lights - these, in fact.
10/35W 12VQuartz Halogen stop/tail bulb BAY15d.....£7.00
12V 20W Quartz Halogen indicator bulb.....£4.00
Would these be a good addition and should the existing wiring be able to cope? Also, am I going to melt the lenses if I fit these?
I had thought about LED lights, but they're not as bright as filament lights, according to some sources... I know there are electricians among us - help!!
Oh, and the email given in the mag is incorrect, so go to the site and find it there.
Posted: Sat Jan 10, 2004 11:35 am
by 57traveller
Could be wrong but is there a legal limit to the wattage of lamps at the rear? Normally 21W max. Sure I've read it somewhere, if so the 35W far exceeds this.
Posted: Sat Jan 10, 2004 6:41 pm
by Gareth
oooh, hadn't thought of that... I'll have to find out.
Posted: Sat Jan 10, 2004 7:50 pm
by Gareth
I found this
Vehicle Lighting Regulations" which seems to clear things up a little.
Stop lamps fitted to vehicles made before 1971 have no wattage requirement, however for all other vehicles, the wattage must be between 15 and 36 watts.
The same goes for indicators.
There is no requirement stated for rear position (tail) lamps.
Well that's cleared that up, but I'm still not sure about the possibility of melting the lenses...
I had a look at Phyllis tonight, and in the dark even the tail lights are quite bright - the reflectors seem in good order. I'm not sure whether it would be necessary.
Maybe if I find some cheap at the Jumble tomorrow, I might have a punt...
Certainly got me thinking. Anyone got any thoughts?
Posted: Sun Jan 11, 2004 12:21 am
by Cam
I had a look at Phyllis tonight, and in the dark even the tail lights are quite bright - the reflectors seem in good order. I'm not sure whether it would be necessary.
I personally think that the Moggy's lighting arrangements are perfectly adequate.
In any case why should you fork out your hard earned cash for someone else's inability to see bright lights!
It makes you wonder where all this will end. Will we all end up driving bright flashing lamps around so everyone can see us? I mean, come on, what's wrong with a little common sense. We don't all need (or want) our rear ends wiping for us now do we??
I'm all for safety, but you can go a bit far sometimes. It's like the old argument against the use of trafficators as the only signalling device. Just because the drivers can't see a flashing bulb does not mean that they should smash into you like a hypnotised sheep

. The presence of the car, it's position in the road and an orange, lit bulb sticking out of the side of the car SHOULD be sufficient!
Posted: Sun Jan 11, 2004 10:47 am
by 57traveller
That's fine then Gareth, glad you checked, saves me a job!
Now I can fit those 2 x 55W spotlamps at the rear to deter tailgaters
Not really.
Posted: Sun Jan 11, 2004 1:39 pm
by rayofleamington
in the dark even the tail lights are quite bright - the reflectors seem in good order. I'm not sure whether it would be necessary.
I'll third that comment - I always found the 1098 rear lights to be good. Accidents are caused by people not paying attention.
However in fog it is easy to see that some trucks and busses had dreadful rear lights which you can't see at 30 metres!!
The only upgrade that may add safety is a rear fog light - even so this is just to compensate for bad drivers. However as motorway fog accidents can be fatal it is probably better to spend money on that instead of higher wattage rear lights?
Posted: Sun Jan 11, 2004 4:11 pm
by 57traveller
Hope Phyllis is off the critical list.
I wonder if drivers of modern vehicles rely more on high level brake lights and don't pay enough attention to the usually lower combined tail/brake lights.
I think as long as lenses are kept clean the existing lights on a Minor are good enough.
Over a period the bulbs darken and the efficiency falls off, its amazing how much better the lights become with just a simple bulb change before they actually fail. The reduction in brightness is gradual and not always noticeable.
I agree with Ray with regards fitting a high intensity rear fog light, a comparitively cheap and simple to fit lighting upgrade without adding too much load to existing fuse box wiring.
Posted: Sun Jan 11, 2004 5:53 pm
by Gareth
Phyllis is very much off the critical list. I'm just waiting for a nice, warmish day to polish her and cut in the new paintwork.
someone else's inability to see bright lights
That's what worries me - they're not all that bright compared to other cars and are much smaller. The tail lampst aren't too bad at night, but they are quite tame when used on dull, cloudy days. Also, their fitment at the base of the wings isn't ideal, so I plumped for a pair of those halogen dealies at the NEC Autojumble. If they work, they'll stay on. If they don't, then I've still got the standard ones, and the others will go on ebay within the month!
Fog lights are all very well, but in low light conditions and light spray I really noticed the difference between my tail lights and those of other vehicles.
I did a bit of maths and there shouldn't be a problem with the wiring, so hopefully all will be well.
As for the 55w spotlight on the rear... that's coming soon!

;)
I might work on a fog lamp, and maybe a reversing lamp next, but I didn't see any of those at the show, so they'll have to remain on the list. I'm not too fond of the rectangular 60's Lucas ones, and those seem to be the only ones available. I'd rather something much more discreet than a lump of chrome dangling beneath the bumper...

Posted: Sun Jan 11, 2004 10:20 pm
by Chris Morley
Sorry to hear that Phyllis had a little bump Gareth - I hope the other driver had insurance. What a pain....
I've overtaken / followed a couple of Moggies at night. The earlier (pre 63) rear lights are very poor - no wonder the tag 'Lucas - prince of darkness' came about. The later lights are a little better, but still not very bright. Of course they are perfectly adequate if you assume all your fellow road users are good drivers who pay attention. Unfortunately I consider a significant number of them to be total imbeciles, so maybe fitting halogen rear lamps is a good idea, especially if you do a lot of driving on unlit roads..
A fog lamp might also be a very good upgrade. I've also found that a lot of people don't understand that a car can reverse without showing a white light. You have to make allowances for other drivers when driving an old car.
Posted: Sun Jan 11, 2004 11:27 pm
by Alastair
For what its worth, I agree with Cam and Rayofleamington - the rear lamps on a Minor are perfectly adequate, provided you keep the lenses clean. If you want a little improvement paint the interior backing white or silver and fit a fog light, but do remember to turn it off when conditions improve. Nothing makes me madder than following someone who has forgotten to do it.
I saw the item about upgrading tail lights in the magazine and my first thought was, if people start fitting those, are we going to end up going down down the road of those horrible modern headlights which dazzle you when the car to which they are attached is on anything but the straight and level?
Alastair in darkest Cornwall
Posted: Mon Jan 12, 2004 12:41 am
by Cam
Nothing makes me madder than following someone who has forgotten to do it.
VERY true, that's one of my pet hates too.
I've also found that a lot of people don't understand that a car can reverse without showing a white light. You have to make allowances for other drivers when driving an old car.
I will make allowances for the reversing issue but the rear lights one is not really on. I mean the bulbs are the same as in virtually all modern cars including my dad's Honda Civic, so it's down to the lenses. Even so there's not THAT much difference and if they can't see the 1/2 ton of steel attached to the lights then they should not be on the road.
Posted: Mon Jan 12, 2004 10:45 am
by Gareth
The light area on our Metro is much larger than that of the Morris, and the intensity appears greater, but the bulb is the same wattage.
The light area on a mate's Astra (ick) is greater still, and the "hammered", complex design of the reflector makes the light much more intense. The bulb is the same wattage.
There is a great difference between the lighting provision of different cars, and if these bulbs help, without causing any problems then all to the good. I thought it would be a good idea to do a "product test" on them, as the club mag was a bit slim on details.
It's not often that I get to see the back end of Phyllis when she's out on the road ('cos I'm normally driving her...) but when I've stopped on a dull day (black car, remember) the tail lights never seem as efficient as those on cars with larger light areas. Well, they wouldn't would they?
Posted: Mon Jan 12, 2004 2:53 pm
by rayofleamington
Gareth,
Are your relectors corroded (ie is the silver part inside quite dull)?
Or are have your lenses gone a bit opaque?
I agree that euroboxes from the last couple of years have very bright rear lights. Driving some new models down windy country lanes I have occassionally wondered if there was a car behind me as the whole road behind was lit up - This was just from the cars high power brake lights, acting more like red flood lights.
5 years ago it was the fashion to have blacked out rear lights - now these really did reduce the rear light power, and all those guys had lights far less bright than the late Minor 1000.
Anyway - good luck with the trial on your high rated bulbs.
Posted: Mon Jan 12, 2004 2:56 pm
by Gareth
The reflectors are in good condition (they'd better be - the lights are new!) and the lenses are still quite clear, but I might yet replace them.
My main worry is the heat issue. If, after a couple of runs, the lenses are hot, I'll take the bulbs out.
I shall report back when I know a bit more.
Posted: Mon Jan 12, 2004 3:53 pm
by 57traveller
It will be interesting to hear how you get on Gareth.
I wouldn't have thought the brake lights will have any adverse effect, they are hopefully only momentarily illumunited with braking. A problem may occur here if footbrake is used instead of handbrake at junctions, traffic lights etc.
Posted: Mon Jan 12, 2004 5:29 pm
by Gareth
Yeah, the guy who sold them said they're not suited for automatics because of the footbrake issue, but I reckon I can cope with that.
I'll feed back when I've been able to take her for a longer run.

Posted: Tue Jan 13, 2004 11:59 am
by 57traveller
Just a suggestion - do your test run(s) in daylight with side/tail lights switched on. Then if you experience any problems you can at least switch them off and drive home in the daylight.

Of course just look out for Rovers in your rear view mirror if the brake lights give a problem.

Posted: Tue Jan 13, 2004 1:50 pm
by salty_monk
If you really want to find out if the tail lights will melt you're going to need 2 things.
The temperature of the bulb at a given distance & the plastic used to mould them.
Any number of plastics suppliers such as BP, Gabriel Chemie etc should be able to supply you with a data sheet that will give you the melting point or fire point of the material. (if it's a thermosoftening plastic it will melt but it's more likely to be a thermoset which will eventually catch fire).
If I was you though I'd get hold of some lenses cheap & try it...
Posted: Tue Jan 13, 2004 3:07 pm
by rayofleamington
temperature of the bulb at a given distance
Actually it's a lot more complicated than that - the 'melting' factor is related to the power (heat) output of the bulb compared with all the heat dissipation factors of the lens and the base.
Even if the bulb doesn't melt the plastic solely by being to close it can still melt it.
If the overall cooling rate is lower than the heating rate it gets hotter and hotter until something burns or melts. Surface area is one of the most critical parts of the cooling rate so if it works in a 1098 rear light it doesn't mean it'll work in a 948 rear light etc..
The worst combination will come with the highest ambient temperature (summer), combined with side lights and brakes lights on simulataneously.
Modern rear light clusters are normally 'vented' into the bodywork which allows the warm air to rise out of the cluster - On the Minor it is fully sealed.
The theory is fine in it's place, however self heating of automotive parts is usually confirmed by testing (aka trial and error!) - even after it is calculated.
The 1098 rear light is quite big so I wouldn't be nervous to just try it.
Let us know how you get on Gavin..