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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
 
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 15,037
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Dave,
I have that exact same shop manual and distributor. The explaination is misleading which leads to confusion. The pot does not work both ways, if the pot performs an action under vacuum it cannot perform the same action under boost using only one input line. When on throttle, vacuum switches to boost which cancels out any function of the pot allowing only mechanical advance. This can be verified by applying vaccum then pressure to the pot.
There is also a schematic of the mirriad of hoses and switching devices for smog that manipulate the vacuum/boost signal. Posting pages from the manual is forbidden on this forum so a hand written schematic should be used.
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RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 09-27-2009, 11:00 AM
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