No load usually equals no boost. But to keep the Turbo constantlly spooled is going to equal an extreme amount of heat. I would suggest an Anti Lag system, but this is not for use on a daily driven car. More to the point the more I read about them, I found they are primarily used in WRC styled events. Anti Lag is actually a Misfiring System (shameless plug for Initial D, those who know will get it!) Anyway I've found after much reading and specualtion of how great it is, hardly anyone will tell you, (from ignorance about it,) that it isn't supposed to be used for more then a certain amount of time. Most writings that I read from a Eurpean test on an antilag system reported Cracked Tubular Headers, hairline fractured Turbine housings, along with destroyed turbine wheel which also leads to the turbos destruction itself. this is nto an everyday use product, however if you don't mind replacing these items often as wel as the occiasional head from warpage of heat, you can usally push the system for nearly 200 KM wihtout fail. (Damn, i wish I knew the source I read that from.)
How it works:
The cheap ones usually involve the addition of an electronic box w/coil, and a spark plug bung in the manifold. When you activiate the system it watches for an RPM drop and fires causing the unburnt gas to exlpode causing the turbine to spool up. The least effective way, there isnt' much unburtn fuel left in your exhaust, see below.
The good systems usually take over the ignition system for your car. The system monitors your timing and when you pull your foot off the gas you timing changing dramatically. That timing change then causes the plug to fire while the exhaust valve is open after no fuel was burned form the power stroke. In laymans terms, that means the you injected the fuel compressed it, didn't fire, and pushed it out, while on its way out the plug fires causing the explosion to happen in the manifold causing the turbo to spool. This is the most effective Anti Lag that i know of.
I know there are more knowledgable people then I to describe this, I hope they see the thread to put straight anything I might have put wrong.