These are the sonics for a .040 68-69 no.9790071 400 block and a .060 73 no.485428 455 block.The 400 block could easily go to 4.210 .The 455 is so bad I almost don't believe the chart.If you add .030 to take it back to stock thickness its still not good.Im hopping my own no. 485428 block is better than this when I get it checked.I will do my 62 389 block when time and money allow.
|