I did some work on some of the cars this weekend including our 68 Butternut Yellow BB car....I thought the performance seemed a little off, so I pulled all 8 plugs (R43XLS AC's)..they looked a little worse for the wear. Our carb doc(Eric) recommended I go to the NGK and increase two heat ranges. So, I got some NGK BPR4ES #7222 plugs, gapped them at .35 and installed. The idle speed increased 200 rpm's on it's own
Car runs strong and smooth now...thanks to Eric for his typical sage wisdom
wilma