Only real way to get that much power is using weber alpha throttle bodies or twin carbs, with 285 profile cams (piper)!

Im using 45mm bodies (£1700ish) and Piper 285 cams (£300ish) with stage one head (£???). I rolling roaded my 1.8 with this set up and got 182bhp and 143lbft, But it costs!