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billjam billjam is offline
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Join Date: Aug 2007
Location: Perth, Western Australia
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Originally Posted by Jim2 View Post
Billjam, my 79 930 stock isolators had an ID of 38mm. Compare these to a set of 1989 930 isolators I had which were far smaller, about 32mm. For effective use of the 38mm isolators you would port the manifold openings and cylinder heads, though you may no longer be interested in doing this.
It's interesting that Porsche reduced the size of the isolators at some stage.
It kind of indicates that they may have had some power or driveability issues as implied by beepbeep and spuggy.
However, I am still inclined to go a little bit in this direction - I'm leaning towards boring out to 34mm.
Old 07-04-2008, 07:20 PM
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