Just my 2c but my tune 4 made 650rw/ runs high 11s. I'm on a stealth 67 turbo, dual fueler, and Brent/LDS sac65 sticks etc. 64mm is about a 600-625hp charger if I remember correctly, some others will max around 640 like the stealth 64g2. 66-68 stock frame chargers normally are limited to...