These injectors are plug and play into the factory wiring harness and install straight into the factory fuel rails with no modifications. This kit was designed specifically for naturally aspirated Nissan and Infiniti cars that are wanting to use both 91/93 and E85 with our tuning solutions. We recommend installing this product close to your tune date and driving easy until the tune is complete. Unless you purchase and install a flex fuel sensor, you will need to switch fuel types on a near empty tank. These injectors have been fully characterized to work like a stock injector, providing excellent startup, idle, and driving characteristics, while providing the additional flow needed to support E85 on your high performance combination. We have seen as much as 14whp increases from going from 93 octane to E85 using these injectors and our tuning, and in many cases, you will pick up more if you are using 91 or 92 octane fuels and switching to E85 from those.Please see attached dyno sheet for results : RED: 2.5" Intake, ISR LTH, MD CBEBLUE: Admin Injectors & Tune 93 OctaneGREEN & ORANGE: Admin Injectors & E85 Availability: Usually Ships in 3 to 5 Business Days Look at our youtube video explaining what injectors to use on your NA VQ