1987 Looper v4 140 RPM only 4000

[nymack66]

Shift rod and new seals installed , bolted up like a glove , Tested in driveway hooked up to the garden hose, Verify complete shift into gears both ways spun it in gear to complete stiring up the old oil then shut her down to do a lower oil change low and behold water in the oil all milky stuff drain it and flush her dry and clean , I expected this since when I remove the old shift rod I felt the rod loose and free i knew the o ring was bad hence the proactive move in ordering one with my new shift rod.
I did not test in the lake as yet!!
I did notice an increase of "driveway idle" increase from 1200 RPM to 2100 since I bolted up the new V4 gear case is this normal ? I am guessing the v4 is less torque to spin verses the v6 gear case that was remove?
Note the original 1200 rpm is driveway idle not in water it drops to approximately to 900 RPM shifted fine.
I am wondering if I drop it into the lake if the idle will drop to an acceptable rpm for shifting or should I plan on adjusting the RPM down ?