Running an apc 13-4. Idled best on 13-6 but 13-4 does better 3d. I might just try an apc 14-4. I am getting 10,500 on the 13-4. I am not sure how well it will transition with an apc 14-4. Slight lag from idle to full throttle. 1/4 and above to full is istant acceleration.