I am starting to build my first mower but I need some help deciding on the engine to use. I have a 20 Hp flathead Briggs, a 25 Kholer commander, and a 14.5 flathead. I have found a v twin Briggs but I haven't bought it yet. I don't want to put a lot of money into engine yet but the goal is to play around on test and tune night at my local drag strip. It seems one of the major keys to top speed is rpm and it seems easiest to achieve with a v twin Briggs with a high rev kit. Is this the path I need to go or will my Kholer be a better engine etc. Any help is greatly appreciated.