Hi all, this is my first post on Rennlist. I am no stranger to car forums as I own a number of vintage cars, but I am a stranger to 928s. I recently purchased a 1986.5 928 S, and its my first Porsche of any kind. Really amazing car!
I am planning to drive the car cross-country in August, and after the initial shake-down cruise of 800 miles, I realized the thing I really want to do quickly is an LED headlight conversion. my vision at night is not what it once was....
I have been searching these forums here for a few days, and after reading through some very long threads the topic that go back as long as 5 years, I will admit it, I am confused: H3, H4, H5, Euro-spec, US-spec, 7", 8"......adapter plugs, plug and play vs upgrading wire harness etc. I am hoping that someone can help by telling me exactly what I need to buy.

the car is currently far from my home, and I will be flying out to get it in a couple of weeks. I kind of have one shot to buy the parts I need to do a quick install before I hit the road. I really don't want to buy some parts only to find out that I needed an adapter plug, or something else that kills my quick install.
Basically I need help with a shopping list of all the parts I need and where I can buy them online, and I need to be able to get them delivered within 10 days.....so special parts from Germany won't meet my needs.
Basically I think I need a 7" LED lens/bulb replacement for the OEM sealed beam buckets that are in the car now. I believe I need H4, but am not entirely sure. its seems like I should be able to buy a conversion kit that will be plug/play.

thanks for the help. I know I am a 928 newbie, so sorry for if my questions seem really basic.

 

There are three headlight options your car may have
1. 7” sealed beams which do not have replaceable bulbs
2 8” USA DOT headlights with 9004 replaceable bulbs
3 8” H4 headlights with H4 replaceable bulbs



For options 2 and 3: H4 (RoW) or 9004 (USA) for you depending on what lenses you have and what harness connections you have. you will need to verify both given they may have been modified by one of the previous owners (P0).

Your USA spec car would have come with 9004 bulbs, lenses and harness connections. But a very common and worthwhile upgrade is to run H4 lenses because the quality of light is so much better. So it’s best to go and look. He lens is identified by either H4 or DOT stamped on the glass. Also check the harness connections.


H4

9004


In either case you can find LED replacement for booth typed just about anywhere with varying configurations, quality and brightnesses. You will likely find you will want to try different options so shopping at a place that has a good return policy can play into that strategy. For the bulb itself you Need to ensure you can match the emitter to the same position as the bulb filament so the focal point of the reflection works properly.

I used this vendor and these lights, they are offered in an H4 and


H4 https://www.jdmastar.com/product/313...-Set-of-2.html


9005 https://www.jdmastar.com/product/317...-Set-of-2.html

for my car I had a USA spec car with H4 lenses, so I ordered H4 bulbs with 9004 drivers so I didn’t have to cut the harnesses. I am very happy with the results, more than bright enough, as good as my 2018 Audi Q5 with Modern LED tech.

also note you will likely need to replace your fog light relay with a standard “53” relay to get everything to work properly. Do a search

good lunch and report back with the direction you choose..

mike

 

The USA 1986.5 comes with sealed beam 7" bulbs. I converted mine with European LHD H4 which is a plug and play conversion using the stock plugs. The 1987+ cars use 9004.
Steve


Passenger's is the OEM sealed beam and driver's is the LHD H4

 

LED bulbs in standard reflectors isn't nearly as effective a combination as the new style LED headlights that come in newer cars and are designed to project correctly.

The better option for 928s is to go to the larger H4 headlamp conversion and then a Xenon bulb with ballasts setup in those lenses. This is what I did in my 928 and then used LED bulbs in the fog light and lower accessory light positions. The headlights are bright and white and work well.

This is probably a larger modification than you want to take on prior to departing after just buying a car, so maybe the LED bulb idea into the standard headlight housings as a temporary fix for the drive home and then a more comprehensive conversion afterwards is the best way to go. Night shot below was driving in light fog so the lights look high and a bit brighter than normal, but give you a good idea of the whiteness and intensity of the light.

 

I am curious, how are Xenon HID bulbs better than LED? I am genuinely interested.

I did a quick google search for comparisons and most of the information I found showed LED's can produce as many lumens (if not more), use less power, are more durable, and last much longer than Xenon HID systems Also LED color is higher on the Kelvin scale, coming in right around a 6000K color, while the HIDs are closer to 5000K (source) . HID Headlights kits produce between 3,000 – 5,500 Lumens depending on the wattage of the ballast you choose 35w or 55w. LED kits have a lumens that range between 4,000 and 8,000 lumens (article).
Based on my 10min of searching it seems as though LED would be the better option, what am I missing?

 

thanks for the info guys. I have the 7" sealed beams, so I need to replace the entire lens assembly with an LED version, and then ensure that the LED plugs connect to the car harness

 

it would appear that this kit will work. that is IF my factory sealed beam lights already plug into a factory H4 socket. are the OEM sealed beams H4?
https://www.topgearautosport.com/172...headlights-kit

thanks

 

As a blanket statement they're not. But when you take light assembly that was designed with a lens and reflector for a halogen bulb and then put an LED bulb into it, it doesn't work as well. The reason has to do with the how light is emitted from the actual light source. On a traditional bulb the light projects outward very uniformly forward and all around the bulb. That light hits the rear reflector then projects forward and is aimed by the shape of the reflector. LED bulbs don't have as uniform a light output because the acual diodes that produce the light are in set spots around the replacement bulb assembly so you tend to get stripes of light instead of nice even light output. In an LED designed light the reflector is different and the bulbs are also designed to project the light forward instead of being reflected.

A Xenon bulb is similar to a Halogen bulb in that the way the bulb emits uniform light and then bounces the light off the reflector works very well - the Xenon light output is just brighter white (K scale) and more intense than the Halogen bulb. So, putting Xenons into a light housing designed for Halogen works better than putting LEDs into that same housing. Now, if you want to replace the complete light assembly with an LED version where the whole assembly is designed around the LED light sources, then that's a different story and that option should work well too, as long as the light assembly is well designed.

 

Thanks, your explanation helps me understand that a a filament help broadcast more light in all directions from the focal point, compared to LED which generally do two sides. Agreed, one advantage the Xenon HID's have is more broadcast capabilities, so they can have a greater effect for a given LUMEN output level (watts). Although, I wonder how much difference this makes in practical application. Is the difference 3% or is it more like 50%? I could not find any hard data on the practical application of this point. Clearly there are pros and cons to both and the OP hopefully has some good insight to make their own decision. In either case the OP will get brighter light by using HID or a LED and if they replace their old 7" sealed beams with something modern, they will get better quality light out of the glass and lens.

Thanks for entertaining my questions

 

I know you said you wanted better light by using LED's, but assuming what you really want most is better lighting - the most cost effective way to get there is probably to get 7" H4 lenses & reflectors from a good manufacturer and put uprated incandescent bulbs in them. Yes I know its not as sexy but they will still look right on the car and I expect they will give you better lighting than the LED set you are looking at. I'd look for Bosch, Hella, Cibie or Marchal 7" round H4 lamps and consider 80W/100W offroad bulbs like Silverstars/Philips. In proper H4 lenses these will work well and won't blind other drivers.

You should be able to do the whole thing for about $150 and have great results and ~correct looking lenses.

If you really want the very best LED results you will need 8" H4 lenses, good H4 LED bulbs and a solution to the cap not fitting. The cost of this solution will be easily over $1000 with new parts.

Alan

 

check out bulbs supplied by this company:

https://headlightrevolution.com/prod...es/bulb-style/

.

 

Huh. I believe that most of the 7" round LED headlights you can get on Amazon are plug-and-play, like the ones for Jeeps and motorcycles. I see them on cars at Frenzy once in a while, and they look kind of odd. Those look a lot better. If that's what you go with, let us know how it went for you.

All of the expert and anecdotal evidence I've seen says that the light scatter from LED bulbs in reflectors meant for filaments is unacceptable. As I've gotten older and as super-bright and LED bulbs have come onto the market, I find light scatter from oncoming vehicles to be more and more troublesome. So, I absolutely won't do that to someone else.

 

I don't see the issue with the link to the kit I posted. its not just H4 LED bulbs, its a kit that includes the correct lens/bucket. I would think that these buckets would reflect and focus the light in the correct way. I do understand that simply swapping H4 LED bulbs into buckets designed for incandescent bulbs is a problem....

 

At this price point I don't expect they will be as good as the 7" H4 option I suggested - that was the point. Would they work - probably (fit may still need some adaptation - I know it says for 928 - but be a bit wary). Aesthetically they do not look like 928 lights AT ALL... so depends if you care? H4 euro style lamps have a sharp horizontal cutoff and work very well on low beams, even with much brighter bulbs. Of all 928 lighting over the years (and continents) the pecking order is this:

Best : 8" ROW H4 with separate 9003 bulbs *
Next : 7" ROW H4 with separate 9003 bulbs (not too much worse than the best)*
Next : 8" USA H5 with separate 9004 bulbs (not much better than the worst)**
Worst:7" USA sealed beams with integrated filaments - no upgrade path - what you have now

* can use uprated bulbs with much higher output quite effectively
** even slightly uprated bulbs will just blind oncoming motorists - don't do it

The difference between the worst and best is just huge. The 7" ROW is the best bang for the buck by far. After-market lamp systems that are DOT compliant will be close to the worst above - IMO it is unlikely any aftermarket complete solutions will be as effective as good condition 7" H4s. Seems you want to get the LED's - that's OK try it - but I don't think you will ultimately be fully happy with them.

You asked for inputs...

Alan

 

I installed a set of 7 inch Cibie H4s in my dad's 944 and the lighting is just as good as the 8 inch H4s I have in my 89.

The Cibies also have a more modern z beam cutoff instead of the e code Hella H4s (also stock 8 inch) that angle upon the outer edge.

They were super easy to install and aim and well worth it even with 55/60 watt bulbs installed. It's amazing how well they light up the road, especially considering their $100 price tag.

The 8 inch H4s you can get from any Porsche dealer/ part supplier but they cost $$$$. Install the LED headlights after you get home so you have less to worry about.