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| Stiffer valve springs - anyone have them? | |
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| Tweet Topic Started: Feb 10 2010, 12:19 AM (2,400 Views) | |
| Dallas | Feb 16 2010, 12:57 PM Post #16 |
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I meant peak combustion pressure between all that boost and n/a |
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| 3tech | Feb 16 2010, 01:25 PM Post #17 |
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Compression, and cylinder pressure are not a factor in choosing springs. One has nothing to do with the other. |
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| mwebb | Feb 16 2010, 01:29 PM Post #18 |
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FOG
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what ? ambient baro = about 15psi at sea level , a bit less at higher elevations . boost = i dunno , 7 8 psi for most OEM turbocharged systems . combustion pressure can get to 500psi , but most of the time very much less depending on conditions and the system involved ... but not relevant as that will hold the valve closed . and in a normal world the cam will not try to open the valve during combustion . so peak valve seat pressure is not a function of the valve spring . the spring s are tested at 28 psi an NA engine may have 20" of vacuum at idle 25" on decel vacuum peak of 12.5 psi which is being resisted by a 28 psi spring ... that works 28- 12.5 = 15.5 in reserve , so you can not exceed 15.5 psi of boost and have the valve close but there is no boost on decel. what relationship are you referring to ? |
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| earthtoad | Feb 17 2010, 07:20 PM Post #19 |
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google "Ferarra" or something like that........ |
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1:54 PM Jul 11