CONTINUOUSWAVE

This is my first post. After reading the forum for many many years I am in need of some help. I have a 1986 18' Outrage powered by a 1996 130hp Johnson outboard (25 inch shaft). I replaced the gear case this past weekend with a unit from a Johnson V6 (gear set went in the stock lower unit). The orginal gear case was the stock unit (V6 dimensionally, with the V4 12:27 [1:2.25] ratio) running an OMC 14.8x17 aluminum prop (OMC pn 0765187). The "new" lower unit has the V6 ratio (14:26 [1:1.86]) and running the same prop, performance, as expected has suffered...With the motor trimmed I am now only able to achieve 4100 rpm with a top speed of 31mph, the boat is very slow to plane (but it will plane running nicely at ~3600 rpm) and has almost no holeshot with acceleration now very sloooow in comparison to what it was. Looking for some advice on re-propping, size, pitch, material, etc...Would like the engine to operate within its full throttle range (5000 - 6000 rpm).

What was your WOT speed and RPM with the old gearcase? Assuming 6000 RPM and 40 to 42 MPH. Clearly you will need to drop pitch down to the 13 to 14 inch range. Because its a V6 gearcase, I believe there are large diameter 13 inch pitch propellers available. I would not continue to run that motor with the 17 inch pitch propeller because you are lugging the motor. Ideally you should have the WOT RPM in the upper part of the WOT range (5500 to 6000).