14x5.5 what tire are you running

High Performance 68 Barracudas came with E70-14 tires on a 5.5 width rim which were about a 25.8 inch outside diameter(OD). That is close to a 215/70R14. That being said, anything with a smaller OD should work. I'm running 225/50ZR15's on our 67 Barracuda with OEM 15 x 7 inch Mirada rims. They are 9 inches wide with 24 inch OD. Playing with Tire Rack's Tire specs on BFGoodrich's Radial T/A it looks like 215 is the largest width recommended for a 5.5 rim. I'd go with that and the profile (I like 60) you like with the highest speed rating you can afford. I like to be below 300 for wear, as I feel they have better traction.