George,

You may not like this....

Here are the valve clearances on my B20E race engine (stock valve train, "D" cam) as recommended by the previous owner... .013" exh and .018" int.

I just had the valves ground on a head that had about 1000 miles of racing at those settings. We reused the valves, as they were all in good shape with no cracks and no burning... they were simply touched up and reinstalled.

I will admit that the engine is run *plenty* rich, so maybe 1000 miles at full throttle is not as detrimental to the valves as it might seem at first blush.

Also for the record, the P.O. admitted that the 142E ITB racing community could never agree on the best valve settings, at least from a maximum power output standpoint. He said the .013/.018 settings resulted from someone spending a bunch of time on a dyno. Obviously, whoever came up with the .013" clearance was convinced that more exhaust duration was clearly a good thing. I would suspect that valve longevity was probably NOT a factor in the decision making process.

Gary L.
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1971 142E ITB racer, 1973 1800ES, 2002 S60 T5