Setback effect rpms?

[Fishiest1]

I'm about to add 4" of setback to my rig.

I was just curious if I was going to lose rpms.

Thanks in advance.

[chris_lacey]

You may lose some rpm due to decreased slip, however raising the engine on the set back may regain the rpm with additional speed thrown in (again due to reduced slip).
If your slip is already good (low) you may not lose any rpm or gain any speed. The set back will likely give you additional bow lift. The trade off is usually worse hole shot.
I liked my V-King with the ModVP and 6" of set back, but the hole shot was much better without it when I powered down to a V-4. Set back likes HP and is not a band aid to make up for an underpowered rig.
The main reasons for more set back are these:
1. May give more bow lift so that optimum hull angle of attack can be achieved without positive trim, and
2. Allows higher engine height for less drag.
3. May also decrease steering torque

[Liqui-Fly]

Setback will cause your motor to run deeper...you have to run them higher.

[350cavi]

Yep, going with set back, and using the stock height the motor was at when it was directly on the transom, it will sit a bit lower in the water. So you will have to move the motor up a bit to regain the "stock" height of the motor.