Im looking to buy a new block for a stroker build but I was hoping to start with a used block. I found a FRPP 306 block for a good price but wil that be any stronger than the stock one I have? I also found a 408 but the block is out of an old 1970 van, am I just better off stick to building the stock block I already have? I am hoping to be able to handle 500hp with the nitrous when the car is all said and done but Im on a budget. Any help is appreciated.