The only issue you need to worry about when running unleaded in a leaded car is valve seat protection. i've been running leaded engines on unleaded since it was phased out in Australia and havent had any issues yet. BUT you must use a "quality" petrol additive to save your seats. My choice is Nulon prostrength octane boost @ 2-3mls per litre as it does the seats and gives you a performance boost as well. [-/
Shiny silver rocks stuffed in fruit bags should be avoided. Besides being useless they can also coat certain parts of fuel systems with muck and cause blockages etc..... :cry:stay away