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The H4 Lighting Roundup (from 944 forum)


The H4 Lighting Roundup (from 944 forum)

Old 06-19-2007, 12:25 AM
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Default The H4 Lighting Roundup

We’ve had a lot of discussion here at the ‘list (and elsewhere) about how to improve lighting in our 924/944/951/whatever. I thought I’d put together a compilation of what we’ve all said before…and what my experience has been. Besides, pictures are worth a thousand words anyway! One note…I’m DEFINITELY not an engineer – I have a degree in communication. So, this is not a technical article; while I’ve made my best effort to make sure this is technically accurate, caveat emptor. With that said, let’s begin!

Want to know what the single best thing you can do for your lights is? Buy a lighting harness. Essentially, it’s a bigger set of wires that you connect into your alternator, to your driver’s side OEM plug, the grounding lug on your frame, and the backs of your lights. The stock Porsche wiring leaves a little to be desired, it’s not very thick and there’s a voltage drop from it running all the way into your cabin (to the light switch), then back to your lights. Bigger wires help all that electricity get to the lights without the drop in voltage. The extra ground makes the circuit more efficient – it doesn’t have to travel as far to ground!

Rennbay sells the harness. Other places sell them, too…and the equipment you need is available if you feel like making it yourself.

Next step is new lenses.

Lens on the left is an E-Code lens, lens on the right is a VisionPLUS:

The view with no lights:

If you’re paranoid about staying “legal” in the good ol’ US of A, stick with DOT-approved lenses. Hella calls them the VisionPLUS lenses. DOT standards (which date back to the 1950s), for the light pattern to be directed up, towards overhead road signs, for example. These lenses, with stock bulbs (55 watt low beams and 60 watt high beams) and a harness, are MUCH brighter than the standard sealed beam. You can also get Xenon and Yellowstar bulbs in the stock wattages.

VisionPLUS on low beam with 60/55 bulbs:

VisionPLUS on high beam with 60/55 bulbs:

If you’re not so concerned about the legality of your lenses, getting E-Codes are the way to go. The “E” stands for “European”. The light pattern for E-Codes is different. It has a sharper horizontal cutoff (pattern doesn’t have to go up towards for road signs) and a small triangle that goes to the right (for roadside signs). These lenses are a MUST if you get bigger bulbs. The pattern is more friendly (I think), even with stock wattage bulbs. The pattern is narrower and puts more light down the road.

E-Codes on low with 60/55 bulbs:

E-Codes on high with 60/55 bulbs:

…and now, for the big guns. The best thing with E-Codes is the ability to run brighter bulbs without pissing off oncoming traffic. Because of the above-mentioned sharper cutoff, those brighter bulbs don’t beam into other people’s eyes! There are a lot of options for type of light (Xenon bulbs, Yellowstars, and just really bright Halogens - 130/90 watt standard halogen bulbs) and for wattage combinations – 80 watt lows and 100 watt highs, 70 watt lows and 80 watt highs, 90 watt lows and 100 watt highs, etc). I currently have 130/90 Yellowstars in my E-Code lenses.

E-Codes on low with 130/90 Yellowstars:

E-Codes on high with 130/90 Yellowstars:

From behind - low beams:

From behind - high beams:

Hella "Xenon" bulbs

I picked up these bulbs recently from (also available at Rennbay). According to the literature, they have a small amount of xenon gas in them, which makes them burn whiter. Or, so they say. These are NOT the cheap-o "blue" bulbs that you see rice rockets driving around with. Those are illegal, and just as well. They're blinding and vision-robbing! They are 100/80 watt bulbs. My plan is to run these for most of the year, then switch to Yellowstars if the weather gets really bad - less reflection off snow, etc. But then again, maybe not. What do I know?

E-Codes on low with 100/80 Xenon bulbs:

E-Codes on high with 100/80 Xenon bulbs:

With any of these modifications, another very useful thing to do is to AIM your lights. Here’s a rule of thumb – park 25 feet away (around three car lengths) from a wall. Turn on your lights. You should have about two feet of the wall lit before it transitions to dark. It’s comparable to most of the visible part of the tires of the car in front of you if you’re three car lengths away. To adjust on a 944, there is an aiming screw on the bottom left of the light housing – it’s easier if you take the black headlight surround off. Turning that screw right lowers the light cutoff, turning it left raises the light beam’s cutoff. You can also aim left to right. That aiming screw is top right. Turning left moves the light to the left, and turning it right moves it to the right. I tend to make my adjustment, then stand behind the car in line with the headlight. I want the bulk of the beam to point square directly in front of me. If I stand directly behind the car in the middle, the beams should be evenly on each side of me and they should cut off evenly at the top.

Questions? Corrections? Post here in the original thread! Happy aiming, have fun seeing where you’re goin’!

***Technical info on the photos - all taken with the following settings on a Nikon D70 at 17mm: ISO 200, F/5.6, 6" exposure.

Last edited by Wipeout; 09-02-2007 at 03:07 AM.
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