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Jeff NJ Jeff NJ is offline
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Join Date: Nov 2013
Location: NW NJ
Posts: 1,187
Originally Posted by Black_Hat View Post
I would get an AFR meter 1st. - make sure your AFR is safe with a healthy margin because of number 2 below

2nd the boost was so low on the 964 turbo due to terrible timing resolution - 3 teeth on the flywheel
and they are not symmetrical. Put a timing light on it under boost and see it jump around.

Mine ran dangerously lean with a 1 bar spring with stock internals - after headers and free flow muffler (rarlyl8) it was way too lean. I then needed rarlyl8 to modify my WUR.
Black Hat is correct about the AFR's. Going from .7 to 1.0 dramatically changes the AFR under boost. I already had the Leask WUR, so I definitely was tweaking WCP, boost enrichment and boost onset to get the AFR curve correct.
But again, once I got it right, I'm not playing with it anymore...

If you don't have a good boost/AFR gauge, don't up the boost until you do, IMO.
1988 930 Venetian Blue
Old 06-29-2017, 09:23 AM
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