throttle body. I originally wanted to put one in each runner and use SS tubing since I thought it would look cool. The problem is running 6 nozzles on a 3 liter engine the nozzles are really small and more prone to plugging. Plus I only need 4gph total at 15 psi boost. If I went port injection with the smallest Devil's Own nozzles my total would be 6gph. Of course run more boost and port injection would be fine.