The most common is a 205/70x15 (or 75 series t be closer to original) but as Amrer has indicated a 215/70 will fit. He has had a lower performance Firestone on his car, he then upgraded to Blockley 205s (Blockley Tyre - Vintage and Classic Car Tyres) but has now fitted Michelin 215s (XWX | Michelin Classic)