1971 TWISTER HOOD AIR INTAKE HOLES....WHAT DECIPHERED HOLES VS. NO HOLES IN HOOD???

Hello to all! Ive researched twisters for this very reason and cant figure it out.......why the 4 inch holes in some twister hoods, but not in the majority?? Anybody??? Maybe the V8 cars had holes from the factory while /6 were scoops only?? Mines a V8 w holes and scoops, but ive seen them either way....any input?? Thankyou!