Thread: Super rich!
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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,557
If the rear fuel pump was not working you would be down on power on boost.
If the WUR was also not energized (all CIS components are daisy chained to the run sequence) then you would also be rich when not on boost. The car would run very badly. Rich off boost and insufficient pressure on boost.

Two fuel pumps are not mandatory for these cars. The fuel delivery system can support twice the stock power level (can you say homologation racing advantage?). The problem with single pump failure is that the failed pump then becomes a drain on the remaining pump. The front pump cannot push enough fuel through the dead rear pump and a dead rear pump cannot pull enough fuel through a dead front pump.
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 10-13-2009, 08:33 PM
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