Or to take it to the extreme...

turn of the overrun fuel cut, change the rev limiter to spark cut (as ^), and then put a 'special' row at the bottom of both your fuel and spark tables. It will be at the kpa well under what you idle/cruise at, and right around the vacuum you're at during overrun. Add lots of fuel, and pull out lots of timing.

I can't promise this won't make bad things happen, especially to your turbo .