Alpha grive swap

[Grub54891]

I have an 1985 larson,140 mercruiser,Alpha drive.Aquired the boat and checking it over found the drive upper is toast.I have a spare driuve but I belive the gear ratios are different. How bad will this affect my preformance?
Originall drive,ser#:689774 1.98R replacement,0c365322 1.84 R Thank's for any advice.I shure hope I don.t need a new upper!
Grub

 

[Bondo]

Re: Alpha grive swap

Ayuh,.... Ya Might find a prop small enough to work,..... or not....

 

[achris]

Re: Alpha grive swap

Whatever the current prop is, multiple it's pitch by 0.93... That will give you the size of the prop needed to get you back to roughly the same engine speed as before...

If it's 17", then you need to move to a 15"
If it's 19", change to a 17".
Etc....

Chris............

That's it folks.... I'm now, 'one of them'...

 

[Grub54891]

Re: Alpha grive swap

Thank's guy's!