DKWalser

There's been a lot of discussion about headlights recently. I've found it interesting and informative. What about the other exterior lights? What are your thoughts on the desirability (and possibility) of upgrading the driving, fog, and other exterior lights?

I spent an enjoyable hour or so last night reading about the upgrades Alan has made to his 928 GTS. (I want to be like Alan when I grow up.) He's added HID to what he calls the fog lights (but looks to be where my S4's driving lights are located) and has upgraded the center brake light to LED. I'm not sure I want to replace the H3 fog lights on my S4 with HID units. While I don't drive in fog often, I'm concerned that the increased light output from HID would be counter productive in the fog.

However, I would like to upgrade the driving lights in two ways: Increase their light output and gain the ability to have them come on without the headlights being on. (On my S4, the driving lights only come on with when the headlights are on bright.) I currently use my fog lights as daytime driving lights. It would be nice to have the option of having the driving lights (with higher HID or LED output) come on when I turn the marker lights on.

What upgrades have you made or are you considering to the lights other than your headlights? On his webpage, Alan says he's considering adding LED turn signals to his side mirrors. That would be cool.

Alan

Understand your lighting functionally before you make any changes... Driving light are auxilliary high beams (that's why they come on with the high beams). So driving lights are HIGH BEAMS (no shield - no cutoff). It would be a very bad idea to have these on all the time... Think!

People might try to disable them for you (in ugly ways) if you did this...

HIDs in highbeam driving lights would also be silly - highbeams by necessity come on and off frequently - re-igniting them every time gets you at least an arc intiatiation flash and dim lights for several seconds while the plasma conditions stabilize (it might also flicker at initiation) - hardly what you want.

I'm glad you are interested in upgrades - but make sure they really make sense and are functional. HID's in fogs is good for DRL use because they stay on (or can anyway in ROW config.) and consume less power than stock lights and are brighter. Now you can't just slap them in - (its far from plug & play) you need to understand beam shape, cutoff shielding and reflector blanking to make it work. More light in fogs is fine as long as it goes in the right place - fogs must have a very low mount (check), very wide beam (to the sides- good on ROW not as good on USA due to placement), and extremely sharp flat cutoff to avoid any light spilling up and reflecting back at you off the fog (to get this means extra work - but you need to do this to make them work as DRL's also and not annoy others with excessive spill.

To my mind the first level of DRL should be to have the marker lights automatically come on (front & rear) then the second level should be to add fogs for better distance forward visibility (of you for others - not for you of others). Porsche forgot the first level here - making the DRL system pretty stupid IMO. Nobody can see you from behind in adverse conditions with just the factory DRL on...?

I still have a partially made LED Aero mirror - but this project is on the back burner...

Alan

OTR18WHEELER

..still waiting for a photochop of a late model 'stang tail lights on a pre '87 928.

Vilhuer

Its mandatory to have low beams on all the time in here. Standard solution is to put higher W lamps to parking lights inside high beams and run light switch on position 1. Some put also fog lights on. Some cops don't like fogs to be used and think parking lights isn't enough. One solution could be to add separated feed for high beams which gives them about 7V. Some younger cars use 7V on low beams as daytime running lights to meet the requirement that lights need to be always on and at same time save some fuel and allow longer pulp life. With correctly adjusted low voltage on high beams it could be possible to not blind others and make cops think 928 was made with daytime running lights. Auxillary lights are mounted so low that they might not realise high beams are used as long as they aren't too bright like they are at full volts.

NoVector

In case you haven't seen it, jump to Ed post at #40 to convert all the other exterior bulbs. It's adictive--easy to spend $350+ doing interior and exterior conversion. But worth it IMHO.

https://rennlist.com/forums/928-foru...ich-one-3.html

DKWalser

Alan -- I did think. (Don't feel bad, other than a slight burning smell, most people cannot tell if I've been thinking.) In this case, my thinking was based on a bad assumption. As I said, on my S4, the driving lights only come on as part of the high beams. My assumption was that the driving lights came on to fill-in the near distance, while the H5 mains were focused further down the road. If they were focused as I thought they were -- basically a replacement for the low beams when the high beams are on -- they'd make good candidates for daytime running lights. They're not aimed like I'd thought they were, so I'll continue to use my fog lights as daytime running lamps.

Alan

Erkka, USA cars don't have the small marker lights in the fogs (its fogs even on ROW right?). You could use the UK's DIM/DIP HL relay and driver unit - then the pods come up with markers in position 1 with low beams on at low brightness. But you have the pods up most of the time - changes the look of the car...

Alan

Vilhuer

I think its aux high beams where 5W parking lamp is but I could be wrong. In any case feeding 7V into aux high would be ok solution as police can see they are not fogs and may think they are low beams when they aren't too bright. Puting main lights up simply isn't an option. If it were, turning knop to position 2 would solve whole issue.

Alan

I have ROW front lighting (all of it), and its in the fogs (outside pair) on mine - I think there was only ever one kind on S4+.

Logically putting a bulb in the reflector messes up the pattern - this would be a problem for a high beam focus, but for a wide fog pattern you don't really care about the center section much - so a bulb in the outboard fog reflector segment doesnt lose light you needed (it would only have been reflected to overlap in the center).

Alan

Vilhuer

No need to put any new pulps in. Just feed 7V into existing aux high. It should light up but be so faint that it will not blind anybody during daytime.