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fredmeister fredmeister is offline
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Join Date: Oct 2002
Location: Baltimore, MD, USA
Posts: 2,235
Originally Posted by gsmith660 View Post
does anybody know at what pressure on the bottom of the diaphragm opens the wastegate should it be what ever boost pressure is?
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.
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
---"When you're racing it's life! Anything else either before or after, is just waiting"

Last edited by fredmeister; 02-20-2009 at 03:33 PM..
Old 02-20-2009, 03:30 PM
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