In fact it isn't a 3i inlet but one from the RS1600i.

The throttle housing from the ERST bolts straight on to the RS1600i one but not to the 3i one.

Also the RSi one is totally in one line (see picture) and with the 3i inlet the throttle housing is bolted on at an angle which makes it more difficult to make a cross over pipe from intercooler to throttle body....