It really depends on the tune. It could have 100kw or 240kw. If the bloke said it has forged pistons I'd assume it's had a 207 transplant. Check the engine number to see if it's the original block or a new one?

I'd be finding out more about the tune status as well. If he did any research at all or the work was done at any reputable workshop, it should have a tune of some sort. Perhaps ask the bloke about it? You can also take it to any workshop and chuck it on a dyno to find out for yourself. Check out evo R section on here. I think it's $80 or something for a dyno run.

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Twin scroll Pig Bi-Squeeling