I started running this engine (in stock form) this past Fall. The car was up to the same pace as with my OS engines. Surprisingly good fuel economy considering I was still running on the rich side. I had no problems making 4mins at SCS during Qualifications. The break in process went really smooth and I feel these engines have great potential. Unfortunately as I started to lean the engine in the last couple of qualifiers it developed a "lean" condition upon opening the throttle at a particular place on the track. I still had plenty of smoke at WOT so the low end needle appeared to be the culprit. As I richened the LEN, I lost throttle response as could be expected but the problem persisted. I slowed the Servo speed a little to compensate for "banging" the throttle open too quickly. Minimal improvement...
It wasn't till I tore the car down weeks after the race that I found that the carb had come loose. 8-(
I will be running this engine again at the Winternats in Florida next month and in addition, I will be testing the "Team" version as well. Beautiful workmanship and good power!