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It is a 090 WUR. The lower CCP/WCP was actually by design. I rebuilt the engine last summer with 97mm (3.1L), 10:1 CR P&C's. This hard start and sluggish cold acceleration has existed since the rebuild. I originally thought it maybe needed more fuel due to the higher compression, so I had the WUR rebuilt to run at lower CCP/WCP's. Hence the lower values.
During that rebuild, I replaced all vacuum lines, injector sleeves, o-rings (inner and outers), intake boot, and the airbox was replaced with new one (old one had crack on underside). Installed a pop off valve, double-triple checked for air leaks from the glue holding it in.
Given this problem existed since the rebuild, I still thought it could be a vacuum leak. So I ran all the leak tests I could in my garage last summer - propane, reverse vacuum and soapy water, cigar smoke, etc. Couldn't locate anything. Brought the car to a Porsche-specific mechanic who ran a smoke test, also couldn't find any leaks.
Still not ruling out leaks though, as it does run lean when cold (in 15's per afr meter on dash).
Couple days ago I discovered something possibly worth mentioning... When I start the car cold, it cranks and cranks, put-puts slowly to life. As soon as the car is running stable (i.e. ~10 seconds after starting), I immediately turn it off. No time for WUR to lean out or engine to warm up. Then when I restart the car, it fires up immediately.
It's almost as if the fuel lines need to be primed first. Don't think it's the CSV, because 5-10 seconds of running shouldn't warm up engine enough to disable CSV in the second start (or am I wrong about that?). Checked residual pressures few days ago, they're within spec.
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