Welcome to lag city
If you're not happy to consider a different turbo, all you can do is put the largest rear on it and be done with it. Don't complain about lag if you're not happy to change turbos
Dont know what happened there, try this;
www.youtube.com/watch?v=qlsiASrwlW8
EDIT: FFS the name is "Formula 1: Michael Schumacher Monza 2006 OnBoard" on youtube. Its 5 mins of pure listening pleasure