906 heads

[darkside]

I was wondering if someone could tell me a little about these heads like yr model and if they are hp's  i know their 906's but here's the casting # 2843906 and on the front 66160  thanks

[Chryco Psycho]

the 906 head was used on all big blocks HP or not  from 68-70 , they are an open chamber casting with 88cc chambers , they are 1 fo the more desirable heads but in realitiy there is very little difference between any production head casting other than the open or closed chamber