QUOTE(L-Jet914 @ Nov 28 2021, 12:54 AM)
I don't why the vacuum T was installed in between with the fuel pressure regulator and decel valve was done to connect the retard side of the vacuum port of my distributor. The port on my throttle body is capped off as pictured. I do know the engine had some major work done to it in the 80s cylinder heads etc. So it now has the configuration of two vacuum t's connected to the manifold vacuum port off the intake plenum giving vacuum to the retard side of the distributor, fuel pressure regulator and the decel valve, instead of just the decel valve and fuel pressure regulator.
@L-Jet914 its possible the retard vac hose set up was modified with the engine rebuild.
the way i see it the one reliable bit of original information is the white engine tune sticker.
that sticker shows only a retard vacuum hose to distributor.
instructs hose to be off for initial idle setting.
there is no hose shown to the right of distributor on diagram to the advance port.
VW has a consistent practice on these stickers across all models to show any hose that is there and to show if it is either disconnected or left connected for the idle setting.
so no hose on the advance distributor would have been the original state of the car.
to note, no hose means no connected hose to anywhere else.
it has to be remembered vw would have fixed a hose on to that advance vacuum port and tucked it under the distributor. the hose in that instance protects the interior of the vacuum port from moisture and dirt. this is how others describe their L Jet set up in old threads here.
from there you get to the throttle body.
it would have had the retard hose connected to the retard port down near the tin on the forward facing part of the throttle body. which it currently does.
the advance port would either not have been present on the throttle body or it would have been capped with a rubber or hard plastic fitting.
for whatever reason along the way, the advance port has been activated.
in a manner similar to a EC-B, but not quite.
its been activated with a manifold source after the throttle plate as well as the source before the throttle plate used on the EC-B. i won't go into that here. it works for you.
basically this one is the
@ClayPerrine version. when it is in its original state.
thats what i work out from what i am seeing. retard connection only to TB.
we have not seen a fully intact version of this yet linking the distributor/TB set up to an emissions sticker and a tune sticker but i'm thinking this is it. EC-A = CP version.
its being installed as late as april 74.
the one on
@JeffBowlsby website is first week of jan 74.
and
@nihil44 has one from november 74.
its great that you have posted the photos you did.
they match the car on
@JeffBowlsby 's website.