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JFairman JFairman is offline
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Join Date: Jul 2006
Location: S. Florida
Posts: 7,273
I have an '87 930 with the IA head and B.L. WUR.
I have the CIS gauges for checking system and control pressure and an innovate LC-1 and G3 AFR gauge in the car.

When I removed the shims you're talking about (mine had 2, a thick one and a real thin one) the system pressure went from 95psi down to 75psi.
I put the thin one back in and fuel pressure went up to 80psi.
I didn't touch the CO adjustment or the WUR.
Idle and 40mph steady speed got a little bit richer, like from 14.3 down to 13.5 and boost enrichment got leaner.
Midrange boost around 4000rpm went from 10.1 up to 11.5
Midrange felt a little stronger and didn't stink like unburned hydrocarbons as much.

But, boost up around 6500rpm went from 12.5 up to around 13.8 and thats too lean up there for the 1.1 bar boost I'm running. I also heard some detonation with the windows rolled up at high rpms.
So, after seeing and hearing that on one test run I put the 2 shims that were under the spring in the fuel pressure regulator back in.

hope that helps.
Old 06-06-2008, 09:26 AM
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