Thread: Ignition Timing
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930turbo 930turbo is offline
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Join Date: Jul 2006
Location: Valrico Florida
Posts: 200
Your '79 has two ports, one vacuum and the other boost. The port on top is influenced by vacuum, the port at the base/front is boost. This allows the vacuum to lean slightly under light load and enrich slightly under boost.

FWIW, I tested my Control pressure regulator (WUR), and found that it does not respond to vacuum, only to boost. This is on my '79 US model.
'77 930 turbo Garretson I/C 1 BAR spring, (2) '82 Triumph Bonneville Royal Wedding Edition
Past rides: '74 914 1.9 liter twin plugged track car, '83 928S, '87 924S, '75 911S w '78 ROW 3.0, '72 911T, '70 911T and various other insignificant domestic examples. Happiness is a grey tailpipe! Turbo's worth the wait!
Old 02-11-2009, 05:20 AM
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