Is it the sticker on the air cleaner????
I had a 7.5 to one, peanut head 454 rated at 270hp in my dually. NOT a performance engine.
454 with good parts in a 70 chevelle, 450 horsepower. A performance engine.
454 dually engine with 10.5 pistons, .600 lift solid cam, big port aluminum heads, single plane intake and an 850 dp, becomes a performance engine.