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twiceblown · 09-27-2005, 04:51 PM

i figure that if exhaust pressure is directly related to intake pressure, then increasing boost from 1bar (2bar absolute) to 1.5bar (2.5bar absolute) [25% more exhaus] then manifold pressures at 22psi would be approximately 40PSI. That means that according to the above measurements,

34mm flapper would require 14.2psi spring
38mm flapper would require 17.8psi spring!!!

All just to provide enough seat pressure to keep the flapper closed while boosting!!!

09-27-2005, 04:51 PM	#40 (permalink)
twiceblown Mmmmm, Boooooost! Join Date: Nov 1999 Location: Disneyheim Hills, CA Drives: 300 yards. Trader Rating: (26)	Re: Measuring stock exhaust restriction i figure that if exhaust pressure is directly related to intake pressure, then increasing boost from 1bar (2bar absolute) to 1.5bar (2.5bar absolute) [25% more exhaus] then manifold pressures at 22psi would be approximately 40PSI. That means that according to the above measurements, 34mm flapper would require 14.2psi spring 38mm flapper would require 17.8psi spring!!! All just to provide enough seat pressure to keep the flapper closed while boosting!!!