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fredmeister fredmeister is offline
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Join Date: Oct 2002
Location: Baltimore, MD, USA
Posts: 2,238
How are you controlling the boost on the wastegate with the device you mentioned?
If it is like other boost controllers that use pressure supplied to the vent side of the wastegate housing to provide more force than the spring is set to go off at then I dont think the spring is the issue.
The spring in this type of arrangement should be set to go off at a lower boost then desired and then the pressure supplied to the normally vented side of the wastegate varies to make up the differential to control the boost.
I would suggest making sure the pressure going to the vented side is being controlled properly because it should be self compensating. Meaning that even if the spring were getting weak at higher engine rpm the boost pressure on the vent side would increase via the contoller to maintain your 20psi set point.
Without seeing your system in detail though it is hard for me to say accurately but this is my experience from how other systems seem to work.
Did you try it in 4th gear to see what happens? Maybe the turbo is running out of capacity or you are not getting enuff load on the engine to generate the boost where you expect.
Just ideas.
1979 930 Turbo....3.4L, 7.5to1 comp, SC cams, full bay intercooler, Rarlyl8 headers, Garret GTX turbo, 36mm ported intakes, Innovate Auxbox/LM-1, custom Manually Adjustable wastegate housing (0.8-1.1bar),--running 0.95 bar max
---"When you're racing it's life! Anything else either before or after, is just waiting"
Old 09-03-2010, 11:06 AM
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