I run the Ballistic 17.5 High RPM with the timing turned to max in the stock class. I've never beaten down the straight, and have plenty down low. Couldn't be happier with the motor. Also can't go wrong with the new Reedy's, I run one in my mod car and it's silky smooth and also runs nice and cool. I ran the 17.5 variety (of the old Sonics) for only a single race day as a loaner when my Ballistic was on order, seemed to deliver great power as well. Probably half of the people at our track run the Reedy's and the other half run the Ballistic and I have yet to hear of anyone unhappy with either.