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Ayuh,..... Not very well, as you'll need a much smaller prop to make up the difference,...I have an Alpha one Gen one outdrive with a 1.98 gear ratio that came off a 1988 3.0 liter. I’m looking at an alpha one Gen one with a 1.84 gear ratio that came off a1990 4.3 liter. Will it work on mine?
go down in pitch about 2" from what you were running with the 1.98. The 1.84 has less gear reduction so you need a lower pitch prop to try and compensate. Issue will be if yo were already running a 15" or 17" prop you may run out of available pitches . If you were running a 19" drop to a 17".What prop adjustments would look at doing? I’m currently using this one
As Kghost points out, if your WOT RPM is in spec 4400-4800 or so (your version of the 3.0 could be 4200-4600) then you can probably drop to a 15" pitch and have similar performance.I’m running a 3 blade aluminum, with a 15” diameter and a 17” pitch.
2000 rpm’s 17.5 ftNeed more info.
Length and brand of boat.
What are your max RPM when at wide open throttle and trimmed up for max performance with you alone in the boat?
It’s an old boat, pushing it 2500 rpm’s was max if I took it to 3000 it was letting me know this is all I gotThat is not correct. You should be in the upper 4000RPM range. Is that a typo?
How old is old?
Why are you wanting to change the drive?
Regardless of the age, If it will not go beyond 2500 rpms without issue, changing the prop or the drive will not solve what ever is your problem.
The old drive is toast and all I do is putt around lake and troll. I was satisfied with the boat and buying a new outdrive is outrageous. I don’t know why I’m even explaining this ****. All im looking for is some boat knowledge that I do not acquire. Like changing outdrives gears pitch and size of prop. Gees.How old is old?
Why are you wanting to change the drive?
Regardless of the age, If it will not go beyond 2500 rpms without issue, changing the prop or the drive will not solve what ever is your problem.
The old drive is toast and all I do is putt around lake and troll. I was satisfied with the boat and buying a new outdrive is outrageous. I don’t know why I’m even explaining this ****. All im looking for is some boat knowledge that I do not acquire. Like changing outdrives gears pitch and size of prop. Gees.
Thank youIf you had said all of this in your first post then you would have received the answer you were looking for.
99.9% who post questions even like your original post are having problems or need to understand like what you asked.
"" will a different ratio drive work wirh my boat"
Without knowing why it is ASS UMED you had a problem of some kind.
In the end, now that you issues/concern is revealed,
You can use any gen 1 drive if you have Zero plans to go above 2500 rpm.
Facebook Market place is loaded with gen 1 outdrives of all ratios.
I found one for a 4 cyl like yours for a friend for $450 complete and in good shape