Just browsed thru last months edition of Car Magazine, UK. (www.carmagazine.co.uk) They pit the new Subaru STi against the Evo X. Some interesting comments;

"publicly, the Japanese engineers quote the 'environment' tuned 276bhp for the 4B11T, privately, they say it'll do over 300bhp easy". I wonder if the Evo X ECU is consciously retarded to conform to some environmental requirements for exhaust emissions.

Also, I was all about to lament the lack of the Evo X horse power until I realised, the Subaru STi it is pitted against is the 2.5ltr version, putting out 300bhp. (Subaru claims, tuned versions can output >400bhp) Both cars have almost similar torque characteristics.

*So (unofficially), tuned 2.0ltr 4b11T can do ~360bhp against the 2.5ltr Subaru doing >400bhp

The article doesn't declare an outright winner, but the writer seems more impressed with the Evo X.

Now, the question is, how much horsies can a tuned 4b11 n/a produce?

Forgot to add;

Quoted century sprints for both STi and Evo X = 4.5secs (5speed manual version)
Mitsu engineers claim 5.2secs for the Twin SSC version

15% more on n/a

anything between 160-190hp for a front wheel drive car will be just nice.