"The YnZ Harness"
There are approx. 60+ different
variations of the 356 wiring diagrams from 56 through 1965 all models
included. As you often hear, shopping around can be a good idea. When it comes to 356 wiring harneses, there really isn't
one that is better than the ones produced by YnZ's
What makes the YnZ harness so special? First of all, each harness
is replicated from an "orginal" harness! If you order a harness for
1958 A Cabriolet,
the happy employee assigned to building your harness, runs
upstairs to get an orginal 58 A Cab harness. Upstairs there
are racks full of boxes containing original harnesses for a wide
variety cars, and yes, the 356 Porsche has its own rack.
The original harness is anchored down on a very long table and
the new harness is built right over the top of the orignial. All
wire sizes, colors and terminal ends are exact to the original factory
specs. Its is a very time consuming process, but well worth the wait.
Another great assest of YnZ, besides the beautiful harnesses, is
the history and intimate knowledge of the 356 wiring variations.
YnZ was researching and building these harnesses long before other
competitors even thought of getting into the game. YnZ has had a
long history with Porsche and many key factory reps in compliling
techincal specifcations and it really shows in their product and
think they are a work of art. Yes, there are other manufactures
that are less expensive, but you know the old saying "you
get what you pay for", with
the YnZ harness you get MORE than you pay for.
Lets get Started
Most of the harnesses that I have installed involved cars that were
complete restorations, so the main tunnel was free of other mechanisms,
making the install much easier.
However there are some common tasks that can be done to make the install
go as easy as possible.
Remove both front seats. The passenger bay is the one I lay in to
"massage" the harness up through the harness bay.
Remove the gear shift lever assembly, you can leave the shift linkage
rod in the bay.
This next item is very critical. Porsche used very sharp carpet tacks
to secure the carpet in place. They used them along the tunnel and
other places throughout the interior. Sometimes you find them along
edge on the right side of the tunnel. Those
tacks penetrate right into the harness channel! Even if you remove
the tack, it leaves a very sharp burr on the inside. You
need to pull these dimples out! If you don't, you will slice the harness
sheathing and possibly the wire's sheathing when pulling the harness
through the channel.
Here is a simple way to pull those out. Get a sheetmetal screw, about
1 inch in lenght, screw it in just a few threads. Now take a claw hammer
and "pop" the screw out.
You may want to "mask" off your dash and any other area you think
might get scratched by the wire ends.
Wire harness Preparation
Preparing the harness is based on the direction of pull as the harness
is installed. I have only install the harness one way and that is pulling
the largest bulk of the wire the shortest distance.
The Harness is divided into three sections:
Section 1 is from the top of the fuse block out to the dash, headlights
and dimmer switch.
Section 2 is the "fuse block" intersection.
Section 3 is from the bottom of the "fuse block" out to the rear
of the car.
There are smaller "spurs" along the way, backup lights,
dimmer switch etc, but these are not difficult to feed to their locations.
Section 1 Preparation
You need to wrap the harness so it can be feed up through the harness
bay. When you wrap this section, try to keep it somewhat oval in shape.
The flatter the oval the better. As you can see by the photo
below, the bay wider than taller. We are going to feed section one
from the narrow end up through the wide end.
Start your wrapping from the fuse block section and move out towards
the end. This keeps the wire from bunching up. Again keep in mind "Flat
Section 2 Preparation
This the easiest section to feed various "Spurs" to their proper location.
The headlights, dimmer switch, brakelight and backup light spur, only
the headlight spur needs to be wrapped.
Section 3 preparation
Again start your wrapping from the first biforcation passed the backup
light spur and work towards the end of the harness. Be sure to tuck
all wire ends in tight, its a snug fit for most models (Speedster is
easy, less wire). The photo below shows the bay you have to pull the
Looks like everything is ready for the install. Clean towel to lie
on with a rolled one to rest my head on. If your comfortable and not
fighting to stay in position, this section should be a snap.
I'll leave it up to you to decide whether or not you want to use "Wire
Lube". If you do, use it sparingly.
Start feeding Section One up through the harness bay. You should
be able to push the majority of this section through, only having to
pull from the larger opening of the bay.
The key is how to feed the harness. Push the harness up until is stops,
then bend the harness at a right angle to the bay and then push forward.
The bending motion is like you are trying to feed wire around a corner.
You should not have to force it, once there is a tail showing at the
upper end you can work the harness with both hands, one pushing,
one slightly pulling. It should look the the photo below when done.
The bar you see in the photo is a piece of lightweight tube steel.
I use it to anchor the harness and to help flatten it, so that when
the fuse block is installed, there is no pressure on it. If you use
the fuse block to "form" the harness you risk the chance
of cracking it. I make up the fuse block last to give it plenty of
time to form itself.
This is the easiest section to feed. It consists of both headlight
circuits, brake light, back up light circuit and high/low beam circuits.
Feed each circuit accordingly. Both the High//Low beam and stop light
circuits are feed through the large rubber grommet in the diagonal
bracing. The stop light circuit feeds through a grommet as well in
the fire wall.
You will need some string/twine to fish through the channel in the
tunnel to assist pulling the harness through this section.
Now I only pull the harness through the tunnel section only. I don't
try to pull through the bulk head all at the same time. The bulk head
exit can be feed through easily by itself. The "tunnel" pull is tight
enough without adding a couple of bends to the pull.
If you want to use "wire lube" this will be the place. I don't apply
the lube until after I see the harness poke through the other end.
Then I apply the lube as the thicker part of the harness is pulled
Once you have completed the "tunnel" pull, you can now "feed" the
remaining wire through the tube in the bulk head.
Go ahead now and route the various spurs to their specific locations.
While the inside of the cab is all setup to lay in, you might as well
start there. Start from the top of the fuse block and route the harness
to the wiper motor, ignition and light switch etc., clamping the harness
with the metal bands under the dash.
Follow the instructions provided by your harness manufactor for making
BEFORE YOU RECONNECT THE BATTERY AND TURN ON THE IGNITION, STOP AND
READ THIS SECTION FIRST!
IT COULD SAVE YOU SOME EXPENSIVE
Installing a wiring harness - Part II "Testing the System"