Canted Valve
 

Hi all
So I'll start by saying I'm not a "cheby" guy (period)
so I don't follow anything cheby..
This morning I was watching (garage squad) and they were working on a z28
I noticed that the heads are canted valve. I that the BBC had them, and I know that
the 55 Chrysler had them Porcupine heads
why is it we never hear about these cheby heads?