so i have this huge airfilter and i was considering options to have it fit where it needs to. I know the best thing to do would be what promotes best flow. the options i arrived at are: since the inlet on my turbo is 2.25inches and the collar of the air filter is 3.5inches, i would buy a 3.5inch rubber plug and cut a 2.25 or slightly smaller hole in the center so it fits tightly around the turbo inlet. having the filter right on the turbo. downside is there isn't a smooth transition and it would by less than 12 inches from my exhaust manifold another option i could do, using my mad fabbing skilz. create an intake plenum that would mount between the turbo and filter, with this i could move my intake away from the hot exhaust but it would put more distance between the turbo and intake filter causing friction in the flow .