VMP Tuning - 07-11 Mustang Shelby GT500 & 05-10 GT 80lb/hr Ford Racing Injectors - Set of 8 New from Ford Racing Used on the FRPP Cobra Jet. M-9593-LU80 High-impediance, works with the stock Ford computer. Rail spacers required when used on the GT500 or 05+ Mustang GT with Whipple Supercharger or Roush Supercharger. FRPP Rail Spacer kit M-8510-M2L required, or select above option when purchasing. Spacers are needed because the above applications use a short injector, these are a long style injector.