It has a 4X46mm Arctic Cat 600cc snowmobile TB's (heavily modified to match 90mm b-to-b distance) on alpha-N. Latest dyno run gave us 164.9kW@7420rpm, 230.8Nm@5820rpm. Torque starts @ 4000rpm, +200Nm available till 8000rpm. Cylinder head is ported and modified for mechanical lifters and we are running a set of CatCams dual springs. Cams are custom grind, 292/304/106 deg, 12/10.4 lift. Home made custom custom 4-1 header with 44.5mm primaries+full DIY racing exhaust system.
Engine was dynoed (chassis) with 94octane R+M unleaded pump gas. Next dyno run will be on higher oxygen content unleaded racing fuel so there might be some more to gain..