gear ratio/outdrive change

[robdobdoo]

i have a 17 foot deep v glassply and have replacd the 4 cylinder volvo penta with a 3.8 l v6 buick. with the current volvo 270 outdrive it took us 12 running hours to blow the engine. it didnt plane until almost 4000rpm and topped out about 31 mph. what is the correct outdrive/gear ratio for this engine and is it easier to change the gears or outdrives? any help would be appreciated

 

[Don S]

Re: gear ratio/outdrive change

Volvo did use the 3.8L engine, it was known as an AQ175A they used a 1.61 gear ratio on it. The 4 cylinder had a 2.30 ratio, no wonder you blew it up.
It's only necessary to regear or replace the lower unit, not the whole outdrive. The upper and intemediate are the same.

 

[robdobdoo]

Re: gear ratio/outdrive change

thanks don
the rebuilt motor is easily replacible but i need to know the best approach to the lower unit. is it easier to replace it, or should i actually replace the gears and are they readilly available?

 

[adensity]

Re: gear ratio/outdrive change

thanks don
are they readily available?

I'm also interested.