What is better H1,H4, or H5?
What is the difference?
I know 964's have the H5 system, can it be changed to a H4 or H1?

Also, i noticed on my rear center reflector has holes that are plugged that you can put a set of lights on them. Has anyone done this conversion?

Thanks

 

All 964s except the USA version are fitted with H4s. The H4 system is superior to the rest.
Conversion kits are available and then you will have to decide on what type of surrounds to use. ROW or USA. I personally much prefer the ROW H4 surrounds to photos I have seen of the USA version which look like little tunnels to me,
Ciao,
Adrian
911C4

 

Adrian & I disagree, slightly. The H-5's (n your car, and soon to be gone on mine, suck) These use the same bulb ususally 9004, as on a chevy cavelier and all the rest. The H-4 that I think Adrian is thinking about is the Hella replacement for the old sealed beam that was delivered on us cars quite some time ago. He is right- the Bezel for these was wide on the top, and had a plastic insert (grey) on the bottom I also think they are ugle, but the Hellas gave good light. The 964 can be updated to use the current H-4's which are aerodynamic, look good, and have painted rings. They are Bosch units, about $250.00 a pair (w/o rings) In those, you can put any bulb you wish. You can fry the retinas of on coming drivers if you like. 2 cautions, however- the Porsche switch is not designed for the higher power bulbs, so you probably should use a separate relay to be on the safe side. The plug from the car also needs to be modified, as the plug wfor the H-5's will not fit the H-4's or the H-1s. I have heard that you can buy adapters. I have made my own. Snipped connectors with about 6" of wire from a slavage yard car, IDed the proper wire in the Porsche harness, and soldered the plug in. Now I can use either light. Best for last: The KIng: The H-1's These are complicated units. Each headlight has two bulbs (H-1, any wattage), and two reflectors, all individually adjustable, so you can have it any way you want. The output is terrific, they are of the aerodynamic design, and you can get painted rings. Downside, they are no longer manufactured, and people who have the want a fortune for the. I Found one NIB one at a garage sale for $50.00, and got two others for $160.00, but had to take these two apart, and used parts of each to come up with one that was up to snuff.

 

Thanks Adrian & Horst,

Horst,

I'm leaning towards changing to the H4's, would you kindly provided me what i would need and step by step instructions, if its not too much trouble.

Is a H4 headlamp unit a direct bolt on to a US 964 to replace the current H5?

Thanks

 

The light will physically fit, but you need to adapt the connector from the car, either as I explained above, or perhaps find some sort of adapter. The rings are also something to consider. I believe there may be versions of the H-4 that have paintable rings (to match your car. I would try to call some of the companies that advertise in Pano.