Think about it though how much technology they did not have compared to what we have now. Basically back then car makers just put somethin together hoping it would run good haha. I don't think their claim is too far off due to the fact it lists on their website the machine work that is also necessary to get that kind of power just by headers, carbs and intake does it make %120 increase no. But with all the machine work and cam I really wouldn't be surprised if those claims are true. Just my two cents
