Ratio swap on OUTDRIVE ?

[scott's vip]

I have a 79 vip 17 ft with a 4 cyl 2.5 iron duke<br />I believe the ratio on the outdrive is 1.55.<br />My ? is the outdrive is toast I found a donor boat it is a 81 with the larger 4 cyl 470 series <br />170 horse vs. mine @ 140 it has a 1.85 with a 21 p<br />prop CAN I USE THIS ?

 

[Frank Martin]

Re: Ratio swap on OUTDRIVE ?

not with that prop with a 15p prop the ratio ends up almost the same

 

[johnkc]

Re: Ratio swap on OUTDRIVE ?

scott, the correct ratio for that 2.5 /120 is a 1.98:1 ratio and it will probably run a 17 pitch prop.