Okay, most of y'all know I have a 78 El Camino with a factory original 305. When I can afford it I plan on a 350cid 290hp GM crate engine. How big of a difference will that be ?? I have no idea what the factory HP and torque rateing is for the factory 78 305. I also have no idea what the factory rear end gearing is, but I also plan on a posi rear with 3.73 gears, and a 700r4 transmission. I think that combo would be a great match. So anyone have any advice or comments ??