I thought the 2005 USDM VIII MR had a normal Evo VIII engine and not that of a JDM MR, as the US MR was only rated at 276bhp I believe
Isn't that the same bhp as the JDM spec (280ps) on which all UK spec Evos are based on?
The FQ340 adds as far as I can tell,
a. new drop in filter (RalliArt?)
b. hard piping kit for intercooler (HKS?)
c. HKS Super Dragger II exhaust
d. Unichip piggyback ECU?
e. other bits of cosmetic changes including the SatNav, leather seats
But the basic engine block should be the same.
The JDM spec GSR has a titanium turbo option, which I think is standard on the UK spec MR FQs.
US spec VIIIs only have the standard Inconel(?) turbine.