ROW H4 headlamp leveling system
 

In the late 1980's and early 1990's (1987-1994?) 911s and turbos in certain markets could have H4 headlamps fitted that had a vacuum operated leveling system, controlled by a dial on the dashboard. I would like to see how the vacuum dashpots are integrated with the H4 reflector assembly, so if anybody has one of these lights, or has a photo of the back side of one, I'd like to see it.

I'm curious as to whether or not this system could be adapted to a regular H4 reflector, or if the reflectors themselves are substantially different.

Thanks,
JR

A year or two back Blackbyrd had a set for sale and posted pics in his thread

Been working on this for a while, I have collected the vacuum parts and was hoping to be able to modify the H4's I have, but I am not sure after checking with various European sources.

Here are some fotos of the headlight...

http://forums.pelicanparts.com/uploa...1423669267.jpg

http://forums.pelicanparts.com/uploa...1423669286.jpg

http://forums.pelicanparts.com/uploa...1423669309.jpg

I had sort of resigned myself to picking up yet another set of H4 headlights (they are available new for around 400 Euros, the option number is M605 headlight levelling option (or vertical aim control) switch is 911 631 231 00, light is 911 631 023 00 near as I can tell.

I would be delighted if someone knew what the mods are to the headlights, it doesn't look too complex, but there appears to be some specialized parts that might be hard to fab up. I was also hoping to find (in Europe) some headlights out of a wreck where I could just liberate the special parts and fit them to one of my good H4 sets.

Any info appreciated...

Dennis

Just like to get this thread going, but where can I get the reflector for these headlights. The only ones I see online are for the ones with the rubber bushes on them.

Cheers

Alex

Hi there, it took me several years to collect all the parts for this option....and my assessment is that you can't fit them on to the standard H4 without some serious modification plus a whole pile of custom parts.

I amazingly was able to trade my H4's to someone who had a set with the vacuum actuators which made the whole thing work for me.

Look, anything that is made can be copied, certainly some of the plastic parts might be able to be printed using a 3d printer, but I worry about their strength and durability especially with the heat from the H4 so close.

I would also note you need the vacuum reservoir (still don't know where exactly that sits or what bracket it uses to hold it in place), plus you need a vacuum fitting on the power brake booster with a small port to feed the system, plus the check valve for the vacuum tank. All those parts are 924 or 944 parts.

The piping is an odd size.....I just ordered two of the longest ones in the parts list - Porsche still carries them and I think it is about $20 for a few meters of the stuff - so it should all come together.

M605 was not a common option - but check the 964 market, it seemed to be more common on those cars and is basically the same system from what I can tell.http://forums.pelicanparts.com/uploa...1646677545.JPG
http://forums.pelicanparts.com/uploa...1646677545.jpg
http://forums.pelicanparts.com/uploa...1646677545.JPG
http://forums.pelicanparts.com/uploa...1646677545.jpg
http://forums.pelicanparts.com/uploa...1646677545.jpg

Reviving thread in case anyone has more info. I found a pair of these off a 964 and since I am looking for H4s to fit my US '89 Carrera, thought it might be interesting to refit. However, does anybody know what might be involved in fitting a US car with the vacuum lines, reservoir, and electrical to actuate? And if so, can I use the headlights before I refit the other bits?

I have the complete system, yet to be operated as the car is just getting into the final stage before engine start up.

The system is fully pneumatic, no electrics and basically it replaces the brake booster check valve with one from a 924 which has a take off for a small hard plastic pipe, around 1.5 mm ID. That gets routed to the switch on the dash after running to a vacuum reservoir which tucks into the big hole on the PASSENGER side of the trunk before routing to each of the headlights. This routing follows existing paths for wiring and windshield washer lines.

The hose is largely hard plastic with custom formed rubber elbows and some rubber hose where it goes onto fitting and such. If you check PET, you can see the schematic of the piping and the lengths.

My plastic pipe was split and not in good shape so I just bought the longest length available from Porsche (PET gives the lengths), paying a price so low I merely screamed - i recall it was the pipe for RHD drive cars and just cut all the pieces from that.

Here is the reservoir and headlight as built just for reference.

http://forums.pelicanparts.com/uploa...1764268782.jpg


http://forums.pelicanparts.com/uploa...1764268806.jpg

Let me know if you need any more help...

D.

Thanks. Found the vacuum bits and dash switch on EBay. Hoping I can figure out the routing of tubing.

Routing is easy.

http://forums.pelicanparts.com/uploa...1764430131.jpg

The vacuum canister goes in the right fender with the rounded end inside the hollow that is there close to the hood hinge. Note that it is horizontal...not vertical as in the catalog.

Part 5 replaces the existing power brake fitting with the small vacuum take off and then there is a 924 check valve put inline a bit further down.

Line 11 is routed under the cowl lip along with windshield washer hose and some electrical

Line 13 routs along the drivers side fender with the hood latch cable, behind the fuse panel - essentially the top edge of the inner fender.

Line 14 routs under the upper front bulkhead lip along with the other wiring that crosses at the front of the car.

There are existing grommets you route into the headlight buckets....note that those are rubber not the hard plastic

Rest of the lines just go behind the ventilation fan to the switch.

On mine there is apparently provision for a tiny lightbulb, but I have never seen anything that fits in there. If I get energetic I may well see if I can fit an LED in it someday as it would be nice to see it lit.

Very simple system, the one I have seen work is amazing and makes a difference in aiming headlights, especially for people who like H4's like me....and those are sensitive to aiming point.

I got my system in parts and luckily scored very good headlights from a guy who had lost the remainder of the system and was willing to trade normal H4 headlights for the ones with the levelling canisters straight across. I was amazed as I expected to pay a premium, but he was happy...and so was I. The other parts I got from a large Porsche scrap yard here in NL, essentially they gave it to me as a box of junk, something like 10 euros for spare cannisters, all the little rubber parts, switch and so forth. The brake booster fitting and check valve are still available from Porsche, as is the fancy plastic line. I just bought 1 of part 13 which is 2.3m of the line, plenty to go around.

D.

Wow. Thanks for the detail. One more thing - I am getting these from a guy who swears they will not fit a G50 car, only a 964. The PET for each model quotes same part number for the assembly. Who’s right?

My car is a 1989 G50 car and everything fit just fine. The indent in the dash was there, the hole in the PS fender that fits the reservoir is perfect and the headlights fit no issue.

I see no barrier for you, keeping in mind like much of the equipment on those cars, it was all added in and Porsche clearly wanted to minimize changes to their cars to fit desired equipment and minimize the annual changes.

Personally, I never worried once whether I was going to be able to fit the system.

D.