My 414 Duster has a Comp flat tappet with specs of 242/250, 106 lsa, 107 ic installed, weighs 3300, 3.55 rear, 28" tires & 4 speed. Makes killer low end & mid range but is done @5400. I have FiTech efi, air gap intake. Timing was locked out @ 34 degrees & was a dog on the low end with a carb. Switched to efi which controls the timing now & it feels like a different car with the increase in low end power. I can be cruising on the hwy @2500 in high gear and floor it. No hesitation, pinging, it just gets up & hauls. Takes a little more rpm when taking off with the stick but so much fun to drive. The thing I love about this combo is from 3000-5400 the torque is at least 450ft;lbs. Peaked 510@3900. I'm sold on the narrow lsa.