yes thats what the do. they also put a larger positive pitch on the blades inside to make it tighter faster. there is a good article in mopar enthusiast years ago about them.. its not 1970 any more. t5ime to stop thinking that way...
have a dynamic converter in our dart. mild 360,904 and 3.23 gears. 9.5" converter, flashes to around 3800 and you would never know it wasn't a stock converter driving the car around until you mash the go pedal... makes the car so fun to drive.
