Gear ratio changes

[spareparts]

you can make it work, I've seen worse, you'lll have to change props(go up in pitch)but keep in mind you can buy a new complete drive, ratio of you're choice from stern drive engineering for around $1200

[brisboats]

Most 165hp used 1:65:1 an 86 4 cylinder alpha one would be 1:98:1. I think you are looking at gen 2 charts or the sei stuff. Yeah you could make it work but you would be better off finding a 470 drive they were geared 1:84:1. Amazing what a prop can do but mercruiser geared em they way they did for a reason.

Brian

[yodaddy]

You didn't mention the size of the 4 banger, but in case it's a 470/3.7L four cylinder motor, they run a 1.84 ratio.

[moneyhole]

It's a 2.5L 4 banger. The guy thinks it just a blown head gasket.
It is not a wise idea or does it really make a noticable performance differance on my motor.
Rear ends are changed all the time in cars like a 3.73 if you are looking to cruz or a 4.10 to get to the end of the 1/4 mile first. If it were your boat, would you do it if you could get the Renken, trailer, & titles for $640?
The only other good option I have is an identical outdrive as mine, used with trim pump arms and complete outdrive with gimbal housing for $500.
I have a brand new water pump for the lower unit already.