If the 91 is in good condition and has been well maintained and you like it than go for it. Sure the 305 is not going to win many stop light races, but since you are only 16 you have many years ahead of you for that stuff. Right now you want a dependable car, that's not going to cost you a fortune in gas, maintenance, tickets and insurance. There are a lot of things you can do to spruce up the car and the engine to make it your special rod.

However if you got money to burn and the 305 just ain't going to get it, then hold out for something else. Another point and an important one, is no matter what you get make sure it is a SAFE car and drive it Safely. Way too many 16 years olds die too soon doing things they shouldn't when behind the wheel.