ok i have a 90 prelude with a t3 t4 51 trim wheel. i also have an ss autochrome external wastegate. i put it all on and the next day my manifold cracked. so for a week i didnt boost. at the same time my downpipe only hung down about a foot. i didnt have my o2 sensor in so it was kinda running shitty but not really. well my turbo when out. shipped it back the the remanufacturer and they told me that the turbine wheel broke in half due to my car backfireing. i never heard my car back fire. if so i think i would have heard it. do u guys have any ideas what could have caused it???

thanx