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mooney265 mooney265 is offline
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Join Date: Sep 2008
Location: New Orleans
Posts: 1,365
Originally Posted by Speedy Squirrel View Post
I am still waiting for the distributor part number, but if this the distributor that I think it is, I have the following comments:
The distributor rotates counter-clockwise.
The pressure capsule mounts the same way as the US version.
Mounted in this way it is not possible to retard the timing with vacuum, only advance it. Vacuum in the capsule will pull the control rod in, which advances the timing.
The capsule under pressure can retard the timing in this configuration.
The vacuum retard curve in the manual is using the term vacuum in the systems sense, as in the vacuum retard system, and not the sense of a negative pressure. I think the chart therefore refers to boost retard at those pressures. The machanism can work in no other way. Porsche would not run a car at 29 BTDC without air temp control, like the C2 has.
This distributor runs on static + centrifugal advance, with boost retard of about 10 to knock it down to 16 BTDC under boost.

check this out - - My mechanic changed out my vacuum pot a couple months back and because i have a '79, told me that my pot [single] wasn't available any more. so, put a two port pot on it and left the vacuum advance open to atmosphere. I connected the vacuum retard to the "E" port on your pictures...

because my dizzie turns couter clockwise, he mounted the pot "upside down" so that it would work under vacuum.

i've attached the pictures of the dizzie and the pot. you can read the number off of the dizzie. my question is: did he do right?

LIVN80S - - Red '79 Porsche 930 Steel Slant Nose Conversion [in 1987] w. 46k miles 3.3L; 964 Cams; K27HF @ 1.0 BAR, with Garrettson Intercooler; Rarly Zork; CIS Flowtech Fuel Head & BL-WUR.

Last edited by mooney265; 03-31-2010 at 07:22 PM..
Old 03-31-2010, 06:21 PM
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