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AFM744 AFM744 is offline
Cynical Misanthrope
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Join Date: Dec 2001
Location: Campbell, CA
Posts: 382
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I have a VDO analog vacuum/boost gauge plumbed from my manifold. At cold idle it reads ~15"hg, or about -7psi. Off-throttle coast-down will reach as high as 20"hg (which is limited by the vacuum limiter, big ugly cadmium plated diaphragm on left side of throttle body). The gauge will swing from vacuum past zero into + boost at anything more than granny-driving, and will read ~15psi (1bar) at WOT. A normally-aspirated car will read highest vacuum at idle and off-throttle and (with a good intake) show zero vacuum at WOT.
X-1, AFM744, Jon, '92 C2 Turbo
JE 8:1 pistons, 964 cams, 38mm intakes ported/polished/twinplugged, ARP hardware, B&B headers/exhaust, 355whp. Full-blown GT35R 3.2 intake EFI pending...
Where my misspent time and money is currently going.
Old 05-28-2008, 07:55 AM
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