Thread: compression ?
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fredmeister fredmeister is offline
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Join Date: Oct 2002
Location: Baltimore, MD, USA
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I figure shouldn't the values be roughly compression ratio times 14.7psi plus 1 times 14.7psi.
For example at 7 to 1 compression 7x14.7 = 102.9 plus 14.7 or 117.6psi.
This assume 100% VE or Volumetric efficiency. In reality it must be less because 100%VE is not attainable at low rpm speeds especially with our manifold design.
This is alot lower number than 120 or 130psi that most guys are quoting. Just theoretically what I suspect to be the case.
Someone else chime in please.....sanity check needed.
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1979 930 Turbo....3.4L, 7.5to1 comp, SC cams, B&B intercooler, Snow Perf water/meth injection, Rarlyl8 headers, Garret GTX turbo, 36mm ported intakes, Innovate Auxbox/LM-1, custom Manually Adjustable wastegate housing (0.8-1.1bar),--running 0.7bar max
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Old 02-08-2009, 04:58 PM
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