It's a 454 stroked and bored to 502, Howards aluminum rods, Arias pistons Custom roller Howards cam made by Don Johansson before he passed. Dart heads, vertex mag, old school weiand tunnel ram with two 650 HP Holley carbs. 14.2:1 compression. It could get more power with a bigger cam and better intake. But Donnie said he didn't want me to kill myself haha. But damn this thing is an animal!