Can't set dwell and total timing short of target
 

Following the advice I've read in every article and message on this board I am trying to adjust the timing on my '73 'S' before adjust the MFI. This is where I've run into a couple of glitches. 1) can't set the dwell below 58 deg, and 2) not getting the mechanical advance from the distributor that I should.

No matter how I adjust the point gap, dwell only varies slightly +- around 58 degrees. Anyone have suggestions what to look at next to figure this out? I'm contemplating pulling the distributor to make sure bushings aren't worn.

On setting the initial and total advance: first thing I found was that sometime in the history of this car someone used a ball bearing to plug the vacum line going to the cansiter on the distributor. With this remove, and the vaccum retard working, I was able to crank more initial advance but I'm still not getting the total advance that I should at 6,000. Again contemplating pulling the distributor to see if someone limited the advance in distributor. Any other suggestions?

Was plugging vacuum lines or revising timing curves a typical solution when fuel quality changed years ago?

Presumably, you are in compliance with the procedure for connecting a dwell meter outlined in this string?

http://forums.pelicanparts.com/porsche-911-technical-forum/67852-how-check-dwell-cdi.html?highlight=dwell

Varying the size of the point gap should produce demonstrable results.

Are you sure that you gapped the points at the correct OEM setting? 58 degrees of dwell, if accurate, indicates that the points are closed up.

Are you sure that you are reading dwell and not duty cycle? I use a Fluke 88 to measure dwell. The reading I get from the meter reflects duty cycle. I then need to compare the reading to a chart that came with the meter and it translates the duty cycle reading into degrees of dwell for a 6 cylinder car. I don't exactly recall, but I think that when the points are correctly adjusted, the duty cycle reading is around 62?? I can check and let you know.

Good luck.

Discussion of the disassembly and cleaning, and all of the pertinent data for your car's distrributor are contained in the thread below.

Current gas available meets all of the octane requirements of the 2.4 MFI engine, and no alteration of the vacuum module on the distributor is needed or required! Yours has been victimized by a person grasping at straws! There is no valid reason to use anything but the factory specs.

http://forums.pelicanparts.com/porsche-911-technical-forum/5432-distributor-lube.html

SmileWavy
Thanks guys, just the info I was looking for. You nailed it, I was hooking up to the distributor side of the coil instead of the purple/black wire. Had a brain fart and didn't even think to search the archives before posting my question.