I bought a early casting cold weather 400 block from AndyF, he had it sonic tested and I retested it with my Dakota 1000 tester, the thinnest place on the worst cylinder wall was .167 down low shruggy
The thickest was around .350, that block clean up at 4.350 and was still running good after 5 years of running it in my S/P car on E85 with no top end lube work


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)