Why? I decided to replace the flakey factory electrical oil pressure gauge
with a mechanical one. I chose the
VDO Vision line
because the looks fit well with the Z's interior and they are high quality
gauges. I chose the mechanical 100psi oil pressure, the mechanical water
temp and a voltmeter.
I bought the gauges from
egauges.com and was
very happy with their prices and service.
The Bracket The first step was to make a mounting bracket. The difficulty with
this is that the gauges are slightly larger than the DIN-sized opening.
I had to countersink the gauges into the bracket. I cut a piece of white
oak that I had lying around into a 7" by 2 1/2" by 3/4" piece. I used a
2" hole saw to make the holes, then used a Dremel to open them up
slightly to 2 1/16. Then I took an 1/8 thick piece of ABS plastic and
with my adjustable hole saw, cut the opening exactly the size of the
gauges. I then glued the ABS to the wood and mounted this to the factory
bracket with a metal strap.
Oil
Pressure line and connection
My car is an NA so I was able to use the turbo oil feed line (arrow) to
connect the mechanical oil pressure gauge. If your car is a TT and you
want to keep the stock oil pressure sender, you will need a T that has
1/8BSPT Male one one side to go into oil filter bracket, 1/8 BSPT female
to receive the stock sender and a - 4 AN Flare (or whatever you want to
use) on the T to connect the oil line.
The fitting on the block is 1/8 BSPT (British Standard Pipe Tapered).
Apparently many people are convinced that this fitting is 1/8 NPT
(National Pipe Thread) because they've been able to cross-thread a fitting
of this sized into the soft aluminium oil filter bracket. Trust me, I am
right! This plug and the stock oil pressure sender have the same sized
threads.
Here are some pictures of the fitting next to the stock plug. Show it to
people who think it is an NPT thread. Part
number for this fitting is 4F3MX-S from
Parker available from Hose & Fittings, etc. (800) 297-HOSE
Here are some pictures with the -4 Braided Stainless Steel Teflon line
connected:
And the run along the back of the engine:
Through the hole in the firewall above the clutch master cylinder
rerservoir:
(I have since wire-tired this and cleaned it up)
And under the dash to the center console:
Mechanical Water Temp sender
location and connection
The mechanical temperature gauge has a sealed line that is permanently
connected to the gauge on one side and the sender on the other. It can
not be separated. It is a little harder to deal with than an electrical
gauge but -in my experience- is much faster responding and accurate.
I got the 96" line on the gauge and ran it along with the oil pressure
line through the same hole in the firewall.
I did not want to remove the upper water pipe and have a fitting welded
in place (or drill a hole into it and tap it) so I bought a brass
fitting at the hardware store and removed the threads with a metal
lathe:
The third gauge is a voltmeter.
Obviously the easiest one to install.
Disclaimer: I accept no
responsibility for the authenticity, validity or legality of the information
linked from this website.
