For me, it has been a range of 17-19 percent comparing engine dyno numbers to chassis dyno numbers. I'm using a 9.5 inch race converter that kills wheel power, but obviously you need it to get down the track. A lock up converter, or a manual is more like 12-15 from what I've seen with others. My engine dyno numbers come from a dyno that uses Depac sampling, so I trust the engine dyno more than the chassis dyno. When you think of everything going on in the car I'm surprised it isn't more of a loss. I know when people do the loss converted to heat calculations it should melt the polar ice caps, but it is what it is.