318 low budget heads change

YY1 said
You sure about those factory compression ratings?

My info shows 8.6:1 starting in 71. The last year for 9.2 was 69 until the "pre mag" roller 318 with the 302s.

That's interesting. I was aware that the compression drop wasn't actually in '72 before it was reversed in '85 but was wondering when it happened.