The Stovebolt Site Forums The Shop Area Engine Shop 216 with zero compression on cylinders 5 and 6

I've read several posts in different forums from folks who put hardened seats in only to have them fail, causing severe damage to the head. One was outlined in the Generator & Distributor magazine of the VCCA that happened to a 30 something firetruck. I've never personally experienced or read of an incident of head damage from unleaded gas. I used unleaded in my old '70 Harley (pre unleaded engine) for years and many miles with no damage. I've been running unleaded in my 38 since '04 with no damage. The general consensus that I've seen is you don't need to worry about using unleaded unless you work the engine hard for an extended period.