TORQUE SHIFT PROPELLER
TIPS AND TRICKS 

I have been experimenting with this on my boat and also found I could see no difference in the performance of my springs and the original ones made by Land and Sea.
 
I have a 19" 350 Chevy IO, carry a full load of gear and people, and find the Z cam has a slightly faster out of the hole  than the ZZ,  but not by much, but  the boat's RPM drops about 500  with the ZZ cams, and  goes 5 mph. faster, using my 30 lb. springs.  All these years I have used LS's Z cams, and am pleased with the new ZZ's.


Trim Tabs/ Prop Shifting in  High Pitch
 
 If your motor has a trim tab, the prop blades  may strike  it as they expand outward.
 
 Mercury does make an extended trim  tab that allows  clearance for the blades. In some cases you can saw off part of the trim tab for clearance, or remove it completely.
 
All the  trim tab does  is keep the boat from  tending to veer to the left or right when running at high speeds. You can handle the boat with no problems.  The later models with power steering don't have tabs.
 
If after that you feel you need a extended  trim tab go to a  Merc dealer.

 
If this is your first time using this prop there is something not mentioned in the literature.
 
The prop springs and cams work controlling the blade pitch from start up to about 3500 RPM.  From there to top speed the blades are moved by the change of  water pressure  differential  on the top and bottom of the blades.
 
On some boats the hull shape and prop angle prevent this from happening on its own. If the final shift doesn't occur, raise the outdrive slightly and bring it back down and that should force the final shift and you'll see the RPMS drop.
 
If that still doesn't do it, lower the boat speed slightly when you're raising the outdrive, which reduces the pressure on the blades allowing them to shift, and then accelerate again. 
 
I have a semi V 19' 350 V8 boat that I have to do that to. It's easy  if you just slow a tiny amount. All my family members know how to do it and people in the boat don't  notice.

Setting  final  pitch with the hub set screws.  The final outward movement  of a blade is limited to the cam profile.
 
If you set the final set screws too far in, the inside edge of the cam, being struck by the guide pin cam break the cams inside edge off.
 
I will not replace a cam that this  has happened to,
 
You can take one of the blades set screws and run it inward  so only 2-3 threads show. Take a blade with cam in it , insert in hub, and turn  and pull outward  until it is stopped by the cam.  This point is the end of the cam's travel.  Adjust each hub set screw so blade stops just short of this position.   You can put  grease in a cam, insert a pin and pull blade out as far as it will go. Remove the pin and examine the position on the cam where the pin stopped. 
 
Land and Seas made changes to the propellers over the years. Be careful which model you buy as some parts won't fit the first 2 models.

1. Props 1 and 2 used a 1" propeller shaft which require a different bearing and cam. They also had 5/8" prop guide pins. The very fist models had no cams but curved slots in the propeller shafts that a tapered guide pin rode in. The shape of the  slot couldn't be adjusted.
 
2. The later props had 1.125" propeller shafts that use the current bearings I'm having made.  The cams are interchangeable in these models and most of the guide pin are 1/2" in diameter.  I will have bushings to fit these also.
 
Contrary to the LS literature, the blades of the same pitch are not all interchangeable. Small variations in the pitch occurred  in machining so when a prop was assembled,  blades were selected that were within 1 degree of each other.  If more than  that a slight vibration could occur.
 
If I have any extra blades to sell you need to send me  the good blades to try and match up with my inventory.