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gsmith660 gsmith660 is offline
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Join Date: Jun 2007
Location: Missouri
Posts: 4,183
Originally Posted by fredmeister View Post
Yes it sees the boost pressure. As long as the upper chamber remains vented to the atmosphere.
You don;t want to cut the spring because like others said this increases spring rate. It will likely not reduce the preload much like you are attempting to control because the spring is compressed a huge amount in the housing, but because of the higher rate will actually make it worse.
Why are you talking 0.5 bar anyway that is aweful low for a 930 engine? Unless you are planning on installing a boost controller to get back to 0.7-1.0bar with the 0.5bar spring.
Don't mess around with this stuff unless you have a good understanding of how the wastegate works and how springs are designed. Take a step back and look at the design or do a little research on google to see how things work before making changes.
Its not a 930 engine its a science experiment with a 2.7 motor and just about the same number that say dont cut the spring also say cut the spring. It makes sense to me that if you reduce the overall length then the preload would also decrease if you can point me to a site that will refute that I am willing to look.
" Porsche there is no substitute" I always liked that saying. Air cooled is the only way to go!
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Old 02-20-2009, 03:45 PM
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