The rules say you must start with a certain HP engine block, the rest of the internal mods and ending CI are unlimited. Start with a legal block, bore it, stroke it, or do whatever you want inside, it's legal. There are Intek twins and Tecumseh twins well over 50ci as well as the Kohlers, and all are 100% legal. They all make big power. It comes down to who has spent the most time getting that power to hook up, and the chassis to handle it entering and exiting the corners. Mike Collins does this very well, and he would be fast with whatever brand of engine he had.
thank you,we gonna nail a cheater next season,but waitn on him to spend big bucks on his motor before we tell him there is a difference in blocks,lol
Why do that? You could potentially lose a racer over a possible misunderstanding. Just inform him you must start with a 44ci block (or whatever is legal in your club), and then bore/sleeve it to the 49ci or whatever bore, keeping him within the rules.