The LT4 Bosch injector is only available here. These are custom modified to work in the LT4. These will fit in an LT1 but the ECU will need to be reprogramed. They are the new style Bosch design III using the same electrical connector and when installed are the same height as the stock Multec. No one else offers this feature. Please Read: Our fuel injector sets are custom fitted to your application. Please tell us your vehicle year, make, and model and leave the rest to us! Each set will be flow matched and come with a USB drive containing the data for your set. Easy installation (less than one hour)Part Number: FICLT4