Ok, sorry for sounding shitty. bottom line is that it is not that simple if you want "most power". What you need to know is that an ok pipe (estoril is great for cash) and your 70 kit and mikuni setup should be decent fast straight up if you read around and tune it right. To go faster you must learn how the engine works and buy go fast parts/get creative.
bullet pipe is fine for getting a bit past 50. probably a few mph's over estoril even. (edited)