distributer w/ advance and retard

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61porsche

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What is the proper hook up of vacumn to a bosch dizzy with both advance and retard?

Let's also assume the following:

1. Was auto trans- now manual.
2. Had EGR ; but now does not.
3. Both vacuum lines at present are hooked up to manifold and not ported as would normally be the case.
4. Has dash pot for carb hooked to vacuum and continues through T to retard side of canister.

My thought- pull all that crap, hook up the advance only to ported ( carb) retime for near max advance? ( 36-38 degrees)

My theory is that the engine is not getting the proper advance or under some scenario is getting too much advance and possibly contributing to a heat issue. Flushed the radiator, changed the stat. Better, but not where it should be.

Thoughts?
 
Thanks, that helps with routing but maybe I need to clarify:

1. The electronic speed sensors and electric valves have gone the way of Jimi Hendrix. Someone, ( genius) hooked it all up to manifold pressure.

2. My thought is that at present with both taps on the distributer hooked to manifold HG, one cancels the other resulting in base advance by mechanical only. This would lead me to believe that in order to run decently the distributer is far advanced which is not good by any definition- timing, valves, best running etc. It does run well, so something is happening. No suspected lean condition. Starts easily.

3. The car exhibits the classic temperature towards the 2 o'clock position, no a/c, and hot ambient- 100+ further reinforcing condition 2.

4. The radiator is clean and flows freely. ( Pulled, flushed, backflushed, etc.) New stat. The fan clutch is locked ( more genius, but maybe budget). Good flow at the expansion tank.

It's a 73 Euro. ( Worth mentioning) There is a sensor in the bottom of the left or front manifold , it's hooked up to the chokes. Never have seen that one either. The right daigram is closest to how it's routed, but again there's no electric valve and speed switch. Just vacuum.

Does the dashpot merely contain a spring that dampens the effect of rapid closing of the throttle? Or is it reverse acting upon a manifold signal switched by the speed relay ( 1900 rpm) ? or does it work the opposite way- only dampens below 1900 rpm?

When all else fails- unhook it all. hook up the ported vacuum source to the advance, set it for highest and best running? Call it a day.

Then see what the temps do, since my guess is there's way too much induced advance at the distributer clamp causing too much overlap that spikes the temps. ( My timing light was not with me and I didn't want to stick my arm down in between the hot radiator and the pully to count teeth on the flywheel.)
 
Thanks again. I'm somewhat used to seeing the Bosch electronic ignition box but not the switch box for emissions.( On a Euro- unless someone federalized it?)

No, two cars side by side, same day, etc. One clocks 3:30 and one at 2. So I don't think it's the guage. New sender too. Mine has never been at 2 even at 107 degrees and a/c. ( sans a bad t-stat.)

On the sender- it's on the front manifold.(low in the water jacket) It appears to be the same wiring as the chokes- green white. No choke, front or back, has a single supply which is what I'm used to. But does appear to be factory originating not near the booster, but between the carbs with the back carb only having two wires- one to the idle solenoid and one only to one side of the choke. I didn't detect any cuts in the harness, etc. So I'm tempted to wire them the way I know works by the wiring diagram off a keyed source.

On the other items- coolant; not any more. ( Mix is better for cooling) No to the wetter is better mix.

Out with the dashpot, plug the manifold, hook up the advance can to ported, retime. Forget about the retard function. There ain't no boost.

Waterpump is next, if the above fails. I just feel like what's left of the funky emissions is making the timing wacked. When I pulled the manifold vacuum off and capped- the engine responded faster; so it likes the advance. ( Didn't check the cam though to see if it was off a tooth or so advanced. mmm.)
 
Looks like the biggest changes for vacuum plumbing was the evolution of the EGR system, which I don't recall seeing on the Euro models. Not much experience with automatic equipped E9's but I could envision additional and different emissions-related vacuum delays that do not appear in the diagrams because the engineers were probably adapting under pressure causing many changes.
 
Maybe more helpful (for comparison purposes) to have vacuum plumbing diagrams in one post. (Courtesy of deQuincey and Dan G)

Euro 1971:

s1mhys.jpg


1972 US:
bav_72d.jpg

1973 US:
bav_73d.jpg

1974 US:

bav_74d.jpg
picture.php


picture.php
 
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