I just want to get my two cents in. Everyone is concerned about weight of a big block and that it will take more power to push the little s-10 the same as a built small block. Taka a small block at 575lbs and you build it to make three hundred and fifty horse. Now you also build a big block chev at a weight of 685lbs and for about the same amount of cash you end up with about 100 more horse power. Say total weight of your vehichle is #3400 with the small block, that is 9.71 lbs to each unit of horsepower. Add in the additional weight of the big block and additional power and you get 7.77lbs per unit of horsepower. The differance there is going to be guite extreme. Even at the same power levels the differance of the big block is only 0.29 lbs per unit of power. Just about the same as having your old lady in the car or a full tank of gas.
But in all reality if you build two engines with different displacements the same the bigger one will almost always out power the smaller.