Extractors for a HZJ105 Cruiser.

Sorry Craig, no first hand experiance, but friend has them on the 1hz 80 and gets a gear better pulling power, so second gear corners can be done in 3rd, etc, and same with hills.
The 100 exhaust goes straight down the tunnel, where as the 80 exits the side...which means the 100 will be better flowing aswell...now you really should look at the rest of the system if you do the extracters, change out the large muffler infront of the diff for a less restrictive one, leave the rear one.
Lastly, consider the benefits of turboing your cruiser instead. The extracter exercise will set you back a little less that 1k, another 2.5 will get you a turbo, and that makes a big difference to pulling power...sort of changes your 6 into a v8, with a small increase in consumption, but usually 2 gears better up hills.
Genie are one of the better extracters, Safari is the best turbo system.
Andrew