87 Carver Montego Mercruiser inline 4's

[Chief's Toy]

I have two inline 4 cyl. 190's on a 27' Montego, what gear ratio do I need?
Also both outdrives were RH rotation and I cannot find any info as to if this was done at the factory or by the previous owner. My question is does anyone know if it will adversely affect the performance of the boat to go with a CR port outdrive like is normally found on dual engine boats?

[Bt Doctur]

470

In a 27ft your underpowered with those. 170-180HP w/ 2 bbl, 180-190HP w/ 4bbl. Gear ratio for the 470 is 1.84-1. Usually swing a 13 3/4 x 21P. Dont believe they had CR back then. No, you can change it to CR by replacing the lower unit and the prop.

[Chief's Toy]

Thank you for the info.