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

Tidybuoy · 01-19-2012, 02:00 PM

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.

Flat6pac · 01-19-2012, 02:58 PM

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

HenrikL · 01-19-2012, 11:20 PM

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.

Quote:

Originally Posted by Tidybuoy

Does the wiring harness at the doors pass thru the same spot as the car speakers?

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

Quote:

Originally Posted by Tidybuoy

I will have a complete harness from door to door as well as the harness that goes to the fuse box (relay).

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.

RWebb · RWebb's Garage

Quote:

Originally Posted by Flat6pac

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

javadog · 01-20-2012, 01:49 PM

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

drcoastline · 01-20-2012, 02:41 PM

Quote:

Originally Posted by Flat6pac

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

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.

Tidybuoy · 01-20-2012, 02:42 PM

Quote:

Originally Posted by HenrikL

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.

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

snbush67 · snbush67's Garage

Quote:

Originally Posted by Flat6pac

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

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.

Quote:

Originally Posted by javadog

No, you have to chaqnge the whole thing. What I was talking about was this; the early regulators are what's known as a parallel arm style. The later ones are known as a cross arm style. Porsche changed the design to the later style becuase it works better. There's a service bulletin from Porsche that describes how to install the later regulators in an earlier car. You can find it here:

http://members.rennlist.com/emcon5/Tech_bulletin_7.pdf

SO, there are two basic styles of regulator. Then, there are manual and electric versions of each style. Further, a coupe and a targa had different parts, as the targa regulators had an additional piece welded on to allow the travel of the regulator to be limited, since there were no frames in a targa window. And, Porsche evelved the design of the cross arm style of regulator several times, so not all of those are the same dimensions.

Confused yet?

JR

Flat6pac · 01-20-2012, 06:32 PM

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?

Jascha · 01-20-2012, 06:48 PM

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

303462 · 303462's Garage

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

Tidybuoy · 01-20-2012, 07:48 PM

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?

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.

RWebb · RWebb's Garage

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.

blee · blee's Garage

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:

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.

RSTarga · 02-02-2012, 02:53 PM

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.

PRE-H20 · PRE-H20's Garage

tidybuoy,

did you convert your windows?

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

daleflesburg · 02-03-2012, 12:37 PM

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.

Tidybuoy · 02-03-2012, 12:51 PM

Quote:

Originally Posted by PRE-H20

tidybuoy,

did you convert your windows?

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

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

Tidybuoy · 02-03-2012, 12:53 PM

Quote:

Originally Posted by daleflesburg

I can tell you that the manual mechanism is at least three pounds lighter than the power unit. No big woop, but lighter.

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.

daleflesburg · 02-03-2012, 01:05 PM

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.