[Silver-911]

Hello everyone! I was hoping I could get a bit of help with making sure my CIS is set up correctly. I had the car at my Porsche mechanic last year to get the WUR rebuilt and he did a few other maintenance items (adjusted valves, oil service, new plugs etc). He also confirmed WUR pressures were correct but the car left not being 100%. He found a few of the injectors to be leaky/poor spray pattern and also commented on the magnecore wires and suggested replacing them. I got the car back with a higher than I would like idle as well, and he mentioned that he did that because it being better than having it too low as he couldn't quite get the car to settle in a happy spot, sometimes it would idle way too low, other times too high. But the idle never hunted, and stayed around 1100 rpm for me, sometimes dipping to 1000ish. More on this later...

I drove the car last summer and into the fall, the car seemed to run OK but had intermittent rough running above 4k, which I chocked up to the leaky injectors and planned to replace them this season.

Being in Canada the car sat for a few months over the winter, but I was fortunate enough to pull the car out of an early slumber and get a few drives in during January and February. As the temps were quite cold I let the car warm up for quite some time and the roads were still kind of bad I didn't push the car at all.

After the first warm day with somewhat spirited driving the car was running great. On my way back it decided to start running awefully above 3k, and more than 10-15% throttle. I could barely make it up a hill. I had just filled the car back up and I assumed I picked up some bad gas. A few tanks of gas, new fuel filter and some fuel system cleaner later, I didn't notice much improvements. I tried to get it back to my mechanic but his shop is closed until April as he is moving.

I decided to order some new injectors and spark plug wires as recommended, and am currently waiting for them to arrive, as well as a CIS pressure tester kit. However, while I am waiting I decided to check the timing as I have a good digital timing light that lets me set the advance. I checked it and it was way off. And as soon as I pulled the vacuum lines to complete the check it would hardly idle. I put the vacuum line sback on the distributor and checked the idle, it was currently sitting at 5 degrees advance, WITH the vacuum lines connected. Almost like the car was timed with the lines connected. I disconnected the lines again and timed the car at idle to 5 degrees and then double checked at 4000-6000rpm and the mechanical advance was working and hitting a fairly consistent 21 degrees advance. I buttoned it back up and took it for a drive.

What a difference. The car pulls harder through the mid range than it ever has. However, I still get intermittent missing/stumble above 4,000rpm and a feeling of lack of power. I am wondering if the leaky fuel injectors could be causing this, as I understand it they dump too much liquid fuel into the runners instead of misting it in as it should and when called upon with a heavy load you get an overly rich mixture as the extra fuel gets sucked into the cylinders. Please correct me if I'm wrong in this thinking. Also, the idle has now settled to a nice happy 950 and is consistent with no missing or hesitation while running.

This has lead me to second guess how the car is currently put together. I pulled the numbers for the WUR (0 438 140 089) and the Fuel Distributor (0 438 100 031) and it appears to be correct for a 1980 ROW car. (body is a US 1976 911s with euro 930 bodywork). But the engine is a 1980 911SC powertrain.

However, it appears to be missing a few components, specifically the decel valve and the thermo time valve. Currently the vacuum system is connected like this:

Upper vacuum on back of throttle body (facing front of car) goes to the lower port on the distributor. Lower vacuum on the back of the throttle bod is going directly to the vacuum port on the WUR. The front vacuum port of the throttle body is going to the upper port on the distributor.

The car seems to start and idle fine while cold, with idle climbing from initial 800-850 to about 1100 until warm where it now settles down to a nice 950 after I corrected the timing.

I know I don't have a lot of info to go on for you guys, as I am waiting for my pressure testor to confirm the WUR functionality and control pressure. However I did confirm their is voltage to both the WUR and the other air valve on the right hand side of the engine. The car does run a bit lumpy when cold though, so the thermo time valve before the WUR would probably fix that. I could try pulling the vacuum line off the WUR while the car warms up and see if it runs smoother until it warms up.

Also, I do have an innovate wideband 02 sensor to install next week which will allow me to confirm the fuel mixture and see what the car is doing while it is running.

I know this is kind of a long and rambling post, so I apologize. I guess what I'm really looking for is some guidance with my current system, what components should I track down and introduce back in, or can I make it function sufficiently with what is currently here.

Also of note, leakdown test was good, the engine is in good mechanical condition with a recent rebuild (probably less than 20,000 miles ago), and valves currently adjusted less than 5,000mi ago.