Prop RPM VS. Engine RPM?

[THRILLSEEKER]

Hey guys when a engine is turning a certain number or RPMs say 6000, does that mean that the propshaft is also turning 6k
I hear people talking about changing gear ratios in outdrives.
Is this to increase or decrease the number of RPMs the propshaft is spinning compared to the engine?

[cobra marty]

To decrease propshaft speed. Ratios can be 1:1, 1.12:1, 1.25:1, 1.36:1, 1.5:1, 1.65:1.

[Vinny P]

Most stock Bravo drives are 1.5:1 ratio. That means that the engine turns 1.5 times to the prop shafts 1.

[THRILLSEEKER]

Thanks guys, do any of you know what the ratio on a stock 330TRS is?

[David]

1.5