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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 14,082
The vacuum readings reflect the overall health of the engine itself, air recirculating devices, engine tune, and modifications. Results will vary at 80mph due to air drag, boost characteristics, and how the engine is modifed or set up. Also the vac reading needs to be taken below the throttle plate to see what the engine sees and not what the intercooler and turbo are seeing. Those who have cut into the brake booster line are seeing manifold vacuum below the throttle plate.
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 06-17-2013, 04:07 AM
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