Classic/Antique Car Repair: 1966 Mustang - 200 6cyl, octane gas, valve seats

Question
Paul, I have an original # matching mustang with a 200 6cyl. it's not driven much, but I would like to know if I should be using lead instead of unleaded gas. Thanks, Andre'

Answer
Andre:

Do you know if the original 6 has been rebuilt in the past? If it was, anytime after about the mid-'70s, chances are it's already got hardened valve seats.

At any rate, this is not a particularly hard-working, hot-running motor, so I'd say skip the lead, but use 89 or 91 octane gas.

If it's the original motor and has never been rebuilt, I'd use a lead additive, just to be on the safe side.

--Paul