Hello
Seems to be my error while past & cut.
However from the IE history those are the possible links:
http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=8720&highlight=distributor+marelli+bosch
http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=29928&highlight=911+t+distributor+conversion+bosch+marel li
http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=28885&highlight=911+t+distributor+bosch+marelli
http://www.pelicanparts.com/cgi-bin/vb/showthread.php?s=&threadid=32442&highlight=distributor+marelli+bosch
Now the marellis are a bit strange and need more attention then the Bosch units.
I never do change the contact on the car, I allways pull the unit complete and work on the bench. Well we ( to company ) have the bench becourse we sevice F-cars as well and you need a bench for Dinoplex or V12 engines. Will safe time.
Ok woun´t blame on marelli the 547 Carrera distributors are also needing a bench.
You always have to grease & oil them when you change the contacts and I worked to often on 914/6 with marellis. Its just inneffective trying to do that in a 914/6 engineroom..
The marellis are just a old design when mechanics where used to oil the distributor every 5000 km.
Now there are some aftermarked contacts around who have a to soft spring. Those will not work on higher rev rates.
Adjusting them is allways a bit close to trail & error sometimes new contacts will "set" after a tesdrive and you have to begin again. A part from the problem is that the little plasticslider runing on the cam will waer in at the first miles.
Not sure about the screws, needed clamp force isn´t that high.
Like said on the long run you will need a Bosch unit as caps and finger for the marellis are nla and even the contact runs into 30$ regions. Now I´m not sure about your car but if you still have a early non CDI unit a petronix, lumetition or similar upgrade will pay back.
Grüsse