When you spot a 420HP ALFA ROMEO 155 TI DTM car at the Goodwood Festival of Speed, the gentlemanly thing to do is shoot a quick video of it, and in this one you can learn about the individual throttle body setup. If you want to make as much power as possible from an NA engine, there are a few challenges involved when it comes to squeezing every last Nm of torque possible in the right places. One common option is to tune the length of your inlet trumpets, aka velocity stacks to suit your preferen