If you don't get the info you need here go to this link at the GT40s forum. Very informative.
http://www.gt40s.com/forum/gt40-tech-engines-induction-...-windsor-engine.html
One of the posters in this thread is running a composite gear.You could join and PM him.The thread is over a year old so he would have some miles on it by now.
They also claim 2500-4000 miles is typical for a bronze gear.
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