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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
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The wear was most likely not due to lean mixtures. Worn rings, clogged oil passages, bad valve guides, those sort of things. If overly lean, especially on boost, the symptoms would be broken rings, holes in pistons, those kind of minor details.

Check and see if that frequency valve is still in place, behind and at the base of the fuel head -easy to see with the engine out. If the engine was originally installed in the '78 and ran that way for some time before you got it, then I'm guessing someone already did the needed adjustments to run without the freq valve. To give you a reference point, I once disconnected my freq valve to see if I could tune around it. My AFR's went from 14.4 at idle, to damn near 17, and I had to adjust the screw in a good full turn to get the AFR's down to just over 15....then it would go lean again as soon as going down the road.

I would suggest that before you run it, get your hands on the gauge setup to test the control pressures in your WUR, and set the ignition timing per specs (probably 0 to 2 ATDC at idle with the hoses connected, and 26 BTDC at 4000 rpms). Or if you can get your hands on a CO tester, you can check the mixture at the exhaust pipe...usually runs best at 2 to 3% CO, adjusted at the mixture screw on top of the fuel head.

Excuse me if you already know all this stuff. Good luck, let us know how it all turns out.
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Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 10-30-2009, 12:02 PM
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