ATK 5.9 Magnum crate motor horse power
@GFlo pretty clear from the link you posted (lower pic) that the ch318a and ch318aa (assembled) are the only heads they are selling. Neither of which they list as a performance variant.
From engine quests old catalog, (upper pic) the ch318b and ch318ba were the performance variants and are not listed. I am not sure what the casting differences are other than some dual intake bolt pattern options. But both are listed as “performance”.
From engine quests old catalog, (upper pic) the ch318b and ch318ba were the performance variants and are not listed. I am not sure what the casting differences are other than some dual intake bolt pattern options. But both are listed as “performance”.
