My engine is still too new to give accurate run times. I still have slight mechanical pinch and a rich tune. I am racing it Saturday on one of the largest tracks in the country. By the time races start all pinch should be gone and the break in shim removed with an aggressive race tune on it. I will be able to give good details on the 9901 pipe and runtimes. My home track is so large and wide open that 98% of the racers do not get 10 minute pits with any engine. So far I have been able to do it only twice with other engines and both times pitted with nothing but fumes left in the tank. We shall see........