What power to expect 20v turbo modded

If I take a 150hp 20v turbo, add a K04, injectors and custom exhaust and run it on std remapped management. What sort of max power could I expect. I know it's not an ideal scenario but just looking at the options.

 

Near 260@6000 and 270lbft peaking at 4500 and dropping like a stone soon after.

 

Is that from experience or an educated guess? I take it a 150 engine with a K04 isn't really optimised for it. Also wondering if you can get big hp figures on a remapped std ECU compared to aftermarket management?

 

You'd be causing yourself a lot of trouble taking a 150 and adding a K04, the cost is ridiculously prohibitive, it uses different oil and coolant lines, so you'd need to buy those, the injectors and FPR need changing, the exhaust manifold needs changing and the downpipe is different.

The best priced option for a 150 is the K03s with larger downpipe and FMIC for up to 240Bhp.
After this look at the K04-001 (a hybrid K03s) or Garret/IHI/ATP eliminators.

 

or get a modded ko3 from owen devloments 300 bhp but the cluch needs done as the 150 cluch cant take the power