Converting to Power Windows from Manual on '74 - any advice
 

I'm going to be converting my car to power windows this weekend from manual. I'm just wondering if anyone has done this before and does anyone have any advice.

I haven't received the new parts yet but FedEx says tomorrow, so I haven't been able to look things over yet.

some questions:

Does the wiring harness at the doors pass thru the same spot as the car speakers?
I will have a complete harness from door to door as well as the harness that goes to the fuse box (relay).

Are there any adjustments of is this a simple switch?

Thanks in advance..................Vern



p.s. for all of you that are reducing weight as much as possible, I will weigh the manual setup and the power setup for your comparison and mine.

The power windows are lighter.
Years ago there was a show done about the Mountain run (Muhollan Drive) in California and the guy went to Porsche engineering to learn how to lighten and set up the car to run the drive fastest and taking out the windup windows saved weight.
Bruce

I will be doing the same operation on my car later and will be very interested in any pictures or information that you may accumulate during the project.

If I read the factory manual correct the power window wires have their own hole.

Did you buy the harness new or used? I have the harnesses that go in each door, but need to buy that part that is under the dashboard.

I often see this rumor -- I never see any data. You also need to specify lighter than what...

Yeah, it's funny, sice there are two different basic versions of the regulator design, not counting the differences in the regulators for things like targas. There are weight differences between the various designs. I don't know that anybody has ever compared apples to apples.

FWIW, in the lightweight cars I'm familiar with, Porsche used manual regulators...

JR

How is it possible? How can a basic wind up mechanism that I estimate at less than two pounds weigh more than a mechanism and a motor? I am sure the motor weighs two + pounds by it's self. Then add the mechanism and wiring.

As far as the harness that goes from the fuse box to inside the car, I ordered it on Pelican. OEM-91161210402 - Genuine Porsche Part: WINDOW WIRING

The wire harness is not here yet and has been delayed - probably because it is coming from Porsche. This was $99


As far as project details: I will take photos and post. I'm hoping to get this installed as all the parts showed up today (except the delayed harness). I may have to keep my windows rolled up for a couple of weeks but I can handle that.

Vern

Bruce ,

You keep posting but that Power windows are lighter, do you have any first hand data to support your claim. I think you are wrong.

The earlier manual assembly as a whole is lighter than the later electric assembly.

When you add the electric motor to the later assembly then it weighs more.

The pictures below are of a manual crank and an electric motor crank.

http://forums.pelicanparts.com/uploa...1306560581.jpg


http://forums.pelicanparts.com/uploa...1306560602.jpg

I m just repeating what I heard on a TV program years ago. Google brought some articles up but nithing about the show I had seen.
Here is a little about the story on PP.
Bruce

What happened to the Mulholland "King of the Hill" RSR?

If you decide to go through it, give me a shout -I have a new right side electric motor crank...

power windows
 

I have all the power window stuff from a 74 targa if anyone else is contemplating this.

The power window mechanisms that I have are the early type (vs the later sizzor type).

I didn't realize until this thread that there are two different types. I hope and I'm pertty sure my manual windows are the same type in my '74. Otherwise, I need different parts.

What would you reccomend for cleaning these up. I'm planning on removing the motors and cleaning away all the grease but what type of new grease should I be using?

http://forums.pelicanparts.com/uploa...1327121248.jpg

By the way, these are not light and I would be shocked if the manual windows are heavier. Regardless, I want power windows and I'm committed to going on a diet to compensate. :)

BTW - I think I have tracked down the source of the power windows are lighter rumor... it is made as an unsupported stmt. in a book on Porsches - IIRC, it might be in Aichele's book.

That's too much work. Unless you are going for "concourse", you can convert to power without removing factory regulators or hunting down factory power window parts. Just slap this on:
http://forums.pelicanparts.com/uploa...1328221699.jpg
Attach the motor behind the door card, slip the flexible drive cable over where the window crank attaches, hook-up wires, viola. Pretty slick. And by the way, I just happen to have a used set I removed from my car if anyone is interested. It's light too - couple of pounds at the most.

I think the origin of "lighter" came with the 934 which came with power windows in race trim. Reason was that the weight savings were deemed inconsequential in this monster by Porsche, not that they were actually really physically lighter. All 930's came with power windows and changing out to manual windows was a pain in the A.. for such little weight.

tidybuoy,

did you convert your windows?

if you arent going to use your manual regulators on the driver side, maybe we could talk.....

I went the other way, not for any reason other than the electric motor lifts were so slow, and I wanted my 74 hot rod to have power nothing, no power windows, no electric sunroof (no sunroof at all), no air conditioning, no heater, no radio, no cigarette lighter, no speakers, and I can tell you that the manual mechanism is at least three pounds lighter than the power unit. No big woop, but lighter.

I'm going to be doing this this weekend or early next week (time permiting). I'm sorry but I promised the old regulators to the guy who sold me the power stuff, so it's spoken for.

Vern

Great, my new muffler is 6lbs lighter than the old so I'm at a break-even point right now :) I guess I won't have to cut out the donuts afterall.

I know, and I do not know what was wrong, but my electric windows were so slow that it seemed to take a minute to put them up or down, and would have to help the drivers side window down in a troll booth so I could pay the troll. And the passenger side was even slower. So, when rebuilding the car I changed back to manual. Surprise, they go up and down really easy. I do not know what was wrong before the motors or the mechanism.

Very interested in how the conversion goes. I have a 74 with wind up windows as well and my arms are getting a little bit of a work out day in and day out!

Did anyone ever end up weighing both the power window components vs the manual window components? There has to be a difference!

Manual Window Mechanisms
 

I backdated. My 74 had electric windows which were so slow that I thought they would not make it, in fact the passenger side sometimes would stall. I bought used manual window mechanism and replaced the electric ones with them. At the same time I put in all new felts in the channels. I like them and they help make it my version of what a 911 with no bling should be (all of the power is the engine, i.e. no power windows, mirrors, no sunroof, no air conditioning, no radio - the one concession is a set of leather electric seats out of a 95 Carrera). My car is a combination of 70s, 80s, and 90s parts, which make up what I wanted my 'outlaw' to be. The windows work with minimal effort and I do not mind the exercise of the left arm. Of course I had to change the upholstery on the doors, and Robert Budd made me new stuff. Note that he even covered the door handle, the map pocket lid and the top trim piece with stitched leather.

http://forums.pelicanparts.com/uploa...1360418300.jpg

The weight savings was just a couple of pounds per door, but 7 pounds savings is supposed to equate to a horsepower, so that is my 2 cents worth.

My own philosophy is remove the a/c, add power windows. Voila: weight savings.

Just completed conversion on the '72 I am building. Even in '72, all the holes are present to snake the harness from the rear of the trunk through to the door hinge area and thence to the door shell itself.

The old parallel-arm mechanism is quite a bit heavier than the later 3-arm mechanism. So if converting from manual parallel arm to electric 3-arm, you will save weight.

Yeah, it's been done several times. If you have early power windows, you can figure in the neighborhood of around 7 lbs. It's a little more than that if you use the newer style regulators. If you have a later car with the later style power windows, the savings is a little less.

JR

If anyone has a set of manual window regulators for sale or trade for a power set I would be interested.

I have these for sale:

http://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/732426-fs-manual-window-regulators.html

I don't need a set of power regulators, as I also have a pair of those.

JR

Does anybody know what the thread is for the winder on the manual regulator?

I tried an M4 and a M5 screw but don't think it either of these.

I think the part number is 911 542 475 00 called a conical screw but seems a bit silly to put an order in just for two screws unless they are special!

Thanks

M5 x .8mm works on the later style regulators. Don't know which ones you have.

JR

Thanks JR - The end thread was damaged so that's why it didn't take it at first & I didn't want to force it.

I ran a tap down it just enough to clear the first thread & all seems good.

I'm car-sitting my buddies 64 C2 Corvette for 2 years - I drive it, do all the repairs and keep it clean. He and I are happy. It has manual windows and manual vent windows and I love it! Simple, light, easy to fix. I have power windows in my 87 Carrera and its slow, makes more noise than it should. Motors are expensive. If it had crank windows, i would be very happy.

Have a body shop replace all of the felts in the window frames. It is a job as the frames have to come out of the doors and the glass too. However old felts get hard as bricks and stall the windows. New felts are like new motor. Ask how I know.

daleflesburg
How do you know?

Because my 74 would almost not raise or lower the windows, and as recommended by a local body shop, we had the felts replaced. It was like the motors were replaced. The windows work great now.

To demonstrate, carefully wet the felts with water. It will soften them enough to give you an idea of how much they are binding the windows.

Frankly,,the PW are a PITA and subject to hours of fun trying to stop binding..I assume the motors are not very strong and any slight bind is enough to cause performance issues
, I am trying to source manual regulators to revert back from power.. if anyone has a set for a 77 Targa..please let me know

You asked for advice.

1. Are doing it for weight savings? Electric motors are not light. Don't do it.

2. Is future reliability a concern? You will most likely be installing used motors. Don't do it.

The 911 cockpit is relatively narrow and power windows are not necessary IMO.

If I forgot to say it. Don't do it. :)

after two hours of working on the passenger side electric window I have determine that I would like to convert back to manual. Once the panels were off I could see that the windows were converted by the PO to the kit that Brian suggested (BLEE)...if any one has this conversion as well...

1

oops..all thumbs

1 Can these be reverted back to manual winders simply be removing the kit?..my reversion could be as simple as replacement winders?
2 Could my culprit be where the cable slips over the original winder?
3 Whats the best way to "get inside" the door to rectify..or is only option small hands and bandaids?

Sorry to dig this thread up...looking into "modern" power windows for my Blasphemy Build. What kit is this Blee?