Turbo timming recommendation?

I add a bit more advance under vacuum at light load. It helps overcome the low end losses before the turbo spins up. Retarding timing throws more heat to exhaust, increasing turbo drive, but also reduces efficiency. Having knock detection is benificial. Fuel mixture plays a large part too. To me a turbo is smoother and easier to tune than a high compression N/A engine. EFI is a great help in tuning a turbo.