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lucittm lucittm is offline
Manassas, VA
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Join Date: Apr 2007
Posts: 1,211
Spring length also has to do with preload. You want the wastegate valve closed "hard" against its seat otherwise it will leak. If you cut down the spring length, you reduce the preload and the valve seat pressure will be less when it is closed.

Now, if you cut the spring down and then manage to stretch it back to its original length (about 6 3/4" in my wastegate) then you have reduced the number of effective or active coils. With less coils to bend, the spring is now stiffer because it has to move each coil farther in one inch of movement. More lb/in.

1991 964 Polar Silver Metallic Turbo Coupe
Old 02-22-2009, 07:11 PM
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