Switched od now prop qusetion

[Fisean]

I recently blew the uppper gearcase gears in my Volvo 200 penta outdrive...after much grief I purchased a used Volvo 270 outdrive. I noticed (after the fact) that the lower unit was stamped 2.10 gear ratio. I have a v-8 and noticed the old drive was stamped 1.61. I went ahead and swapped outdrives anyways, thinking I could experiment with props to alieviate the gear ratio dilema. I put on a 14 X 21 prop and only could muster about 20mph at WOT 4200rpm.
My question is should I swap out the lower unit back to my old gear ratio or am I on a endless path trying to compensate with a radical pitch on the prop.
With the old set up I was able to run at 28mph at 3000 rpm with a 14X19 ???Thanks for any opinions in advance!

 

[hwsiii]

Re: Switched od now prop qusetion

Fisean, I think I already know why you blew up your old outdrive, but would you please tell me what your maximum RPM and speed was with the old outdrive.


H

 

[Fisean]

Re: Switched od now prop qusetion

Fisean, I think I already know why you blew up your old outdrive, but would you please tell me what your maximum RPM and speed was with the old outdrive.


H

Maximum rpm was 3,500 speed was between 25-30mph. I blew the upper when I hit a log as far as I can tell...it was more like a floating telephone pole. I have been pondering this after posting. Think I need to change out the lower unit back to the one I had on originally, and go with the original prop, hopefully a 200 lower will fit the 270 intermidiate. On a side note....will a lower unit that came off a 200 fit on a 270? It was replaced once before and not sure if the bearing at the top fits the race on the intermediate.
It ran so perfect before, not sure if I can compensate with a prop with a short hub.