lessons learned on 2/1

Well seems I didn't allow enough area for expansion of gases at the 2/1 collector outlet, and so too much back pressure blew the rear mid pipe out of the header adding, stronger springs plus one more helped but NAH, after discussion with other engine builders we concluded bigger extractor pipe from the 2/1 collector and big outlet in muffler. So here it is finished the mod this weekend so another track day looming to do some more testing.