View Single Post
Registered User
Join Date: Jul 2004
Location: Buena Park, Ca.
Posts: 836
Porsche Crest Beautiful Car!


1st, I really like the way your 930 came out. I really love that color and hope you show some interior shots as well. You should be very proud.

I can put my two cents in, with my background in the Petro-Chem Industry. 1st, the factory waste-gate in question is nothing more than a PRV Pressure Relief Valve. This valve is designed to release at a set pressure or psi. In the case of the factory wastegate, the point of release is determined by the strength of a spring.

A factory waste gate spring is set for.8 bar. One can purchase heavier springs, which require more psi to make the waste gate release. As a result, an increase in forced induction will take place. As we all know, unless an engine is properly designed for increased boost, it is best to stay with a factory setting of .8 bar

If the openning of a factory waste gate at full release is larger that any of the GHL exhaust system....I would be shocked. That would be the only way logically that header system would be at fault. An outlet is only as efficient as the inlet.

With your specs described....your problem resides within your PRV. I would install factory .8 bar spring and test that under .8bar psi...the diaphram not only opens...but opens fully.

Lastly...having owned my 930 for more than 8 years and clocking over 120K miles myself, I have found the best way to make that car not by focusing on more horsepower....but by making the car light. I have dropped close to 300lbs off my car. Think of how much more horsepower it takes to propel an additional 300lbs. See pic of what I've done. BTW, I'm still running a factory I/C under the duck-tail.

I really hope you can solve your problem soon.

All the best Lewis,

1970 911 (SLVR/BLK/SRD)
930 RSR in "Excellence" Sept 2007 (SOLD)
1983 911SC EURO (SOLD)

Last edited by PAUL RODELO; 02-22-2007 at 10:46 PM..
Old 02-22-2007, 10:42 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #27 (permalink)