Looking for a Lower Unit for a 1985 V6 SPCLK (220 hp)

[jd fishnboat]

I've been all over the net and my eyes are starting to bleed. From what I've gathered the lower unit for this particular motor is supposed to have a 1.75 gear ratio. Most of the "150-225hp" lower units I've seen are 1.86 or 2.0 gear ratio.

Does anybody know if I can use one of these other lower units and just change the prop if I don't like the top end/low end of the boats speed?

The motor is in a 1986 20' nitro bass boat

jd