cyclone has a different intake manifold w/ secondary intake butterflies iirc, along w/ cyclone stamped on the IM and i think the valve covers were red....but the IM is useless in that respect w/out the jdm ecu to control it...not worth worrying about if you ask me, and yes you can use the IM w/ out the ecu, i had a cyclone in a 1g awd w/ usdm ecu....and if youre looking for a motor dont be fooled by advertisements for the 4g63t that label them as jdm/usdm....theyre one in the same