Stock 360-2bbl melling cam is spd25. I think the 340 cam is spd22. I've used a couple of those 25s before in 318s, noticeable win power, idles like stock 318 cam. Exactly the same thing as the comp 252 minus 0.015" lift. Duration and overlap are dead nuts the same as the comp at a cheaper price. Good for a mild " 1 step over stock" cruiser. The first one I used was on a D250 that I towed a bunch with. Mileage improved over stock cam, too.