<VV> Corvairs

[shortle]

My nemesis with Corvairs (lately) seems to be with their valve seats coming loose from the heads. This has happened to me twice in about 25,000 miles. First was with 140HP heads (intake seat exploded) and then it was with 95HP heads. The 95 was an exhaust valve. Both of these heads were very deflashed long before the seats came loose. Neither of these were ever overheated in the time I owned them (don't know about previous history).What is the solution to this? Can something be done to keep this from occuring? Neither time was it warm outside nor was the engine under any extreme load. The vehicle is my '63 Rampside with a 1965 RN engine, 3.55 diff. and a PG.I am using the 12 plate oil cooler with both side covers and the OTTO parts pan and valve covers. I hope to get some answers and suggestions from ALL members regardless of race, sexual orientation, age, political beliefs, education, life experiences, etc.
Thank you in advance for what I hope is an interesting thread.
Timothy Shortle in Durango Colorado
Getting ready for our tri state meet next weekend