Re-work heads or use fuel additive for leaded SB?

I would use at least 89 octane. if you try an additive for cleaning? try Lucas Fuel Treatment.

a.. A great tune-up in a bottle b.. Cleans and lubricates the fuel system c.. Neutralizes low sulfur fuel problems d.. Increases power and miles per gallon by burning excess exhaust emissions e.. Increases the life of pumps and injectors I have found that Lucas is by far better than the others.

my2¢

If you pull the heads just have hardened valve seats installed. Then go through the rest of the head, new valve guides, drop some new valves in it, and replace the springs, retainers, locks and use umbrella type seals. If the rocker studs are press-in, have screw-in studs installed. Also a new set of stamped rockers would make the job complete. Make sure your shop checks the pushrods for straightness and deformed ends while you at it.

lib wrote:

There is no real need for the harden seats. There will be extra wear, but not that much. In 80,000 miles, she will need a valve job instead of

100,000 miles. Realistically, what are the chances of reaching 80,000 miles on a '63 Corvette these days?

Also, if the seat is faulty, it can drop and create a lot more problems than the extra wear from the standard seats. Figure that in 80,000 miles, she has to do a $200 valve job vs. the potential for an entire engine rebuild by trying to go 100,000+ miles.