Hello Hyamyule ( I hope I spelled it right ). Why wouldnt you of bought the car if you knew the 302 wasnt the original engine? The 302's didnt start finding there way into mustangs until late in the 67 production year. Before then it was just the 289 in 65 and 66. In early 65, also know as 64 1/2 coupes, there was an option, 260 v8, or 289.
Look on the vin#, the 5th digit should be a T for a 200 inline six, or if its early 65, U for 170 inline six.
Either way enjoy your stang, shouldnt be to hard with a 302 in it.
. I've been restoring these cars, and working on my 289 coupe for a while, so if you have any questions feel free to ask. If I cant answer it I'm sure they'll be some one else who can.
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64 1/2 Red Mustang Coupe. 289, C4, 3:1 rear gear. Mallory duel point. Ported & Polished 65 heads shaved .01 with 351 windsor valves, high side of 10.5:1 comp, 1.7:1 sled rockers, blue wolverine lumpy cam, autolite 4100 Hipo 4 barrel. And to many others to list
2000 Perf Red Mustang GT. 5spd.
64 1/2 red 6cyl coupe. Auto. project car.