I just finished my custom sachs intake that i made from a puch header. I am putting a 17mm round bing from one of those magnum x's. My setup is a 505/ 1D with a welded biturbo. I am currently going about 33 mph with the stock setup. I was just wondering what kinda performance i could be expecting by getting rid of that stock 12mm and adding the 17. I also plan on doing some porting but ill save that for later. Thanks for the input!