In my opinion a stock 454 has plenty of torque for most types of wheeling and the weight issue I don't really see as a problem, K5's are not exactly lightweight and a 100 lbs extra you won't notice with all the extra torque you will have. In addition to that I am sure that my stock 454 with 4 bolt mainbearings will last longer and take more abuse than a built 350 or 383. I love my fofittyfo /forums/images/graemlins/waytogo.gif