pipes
I'm sure Curt's pipes are the high RPM version.That's what he said. He didn't run them much. They should run 10,100 or so depending on the motor.They do look a lot like Howlers because they are "hydroformed" like the Howlers. The center sections are smaller in diameter though.
I had Dave build me a set of his pipes years ago in the lower RPM version. They have longer header sections and run at 9200-9400 RPMs. They are now on one of my brother's sleds and work very well. When Dave built pipes he gave the option of open stingers or silencers.