Simon Norris i think uses the theory build a high power N/a engine then turbo it

He built a cossie a few years back that i had the pleasure of being in with higher comp than std went really well with over 600bhp too

With the more controllable ecus there are now and the big roller bearing turbo's which flow more helps keep the temps down hence higher comps and more ignition can be used for more power

Only if you know what your doing !!and there are only a few that do

Paul