We talk about actual media. The burner will not burn slower than the slowest speed his firmware tells him for the mediacode. And the slowest for all 16x media is 4x for most 8x and 4x media it is 2x -R and 2,4x +R. If you use antique media he doesn’t know he will burn with an universal strategie probably also 4x or 2x but I havent’t the case until yet.
So it might be a solution for you to find 8x -R media TYG02 is still available. But I will have some doubts that they will run burnt with 2x when they didn’t do it burnt 4x whatever your cracking faq is saying.