I know I cant be as much help to alot of your questions because I'm fairly new to my m44 but I had an e39 before this. Yes, at least my m44 is giving me cooling issues. But there is a thread on here that gives in full detail, and pictues of how to rebuild your cooling system. As far as performance goes, I've seen a few turboed M42's but Downing used to make a supercharger for our motors. But from looking they no longer make them. And a used one will cost you around 2500 |