Recommended tire size for 14” rallye wheels on 63 Dart .

My 63 Dart came with 13” tires, probably 6.50x13 Want to put more tire on the car to improve driving, it gets really skittish once you get above 60mph.Any suggestions.I bought small bolt pattern Chrysler rallyes so wider tires are possible but what will fit in the wheel wells ?
Not a fan of Rallye wheels on early A bodies. That's just my opinion. I like steel wheels on them, especially the 14" x 5.5" Chrysler steel wheels. Here is a pic of the mentioned wheels, with 215/70-14 tires. 205/70-14 or 215/70-14 both work well on A bodies.

Picture 695.jpg