The 428 is a rare and interesting British sports car. Although never fully developed by AC the better models are the pre 1969 examples with the "fighter pilot" dash instrument layout. Cars handle and drive well but mark IV Cobra improvements can be made to both engine and suspension to give eye watering performance.. Often said to be very expensive when new - however it easily out-performed the Maserati Minstral, Ferrari 330, E-type Jag. and Aston Martin DB6 only a Ferrari 275 could accelerate faster than an AC 428. Currently undervalued, Most parts easily obtained except for body parts. Good owners club.