Gear Ratio Question

[Jajbs920]

2006 Opti 200L SN 1B379785 hanger with a mid to late 90's 225 EFI powerhead
2007 Triton 197 Magnum
I recently purchased a used lower unit that came off a 2000 225 EFI and ASSUMED it was the same ratio as what I was running...was told it was anyway. I went and ran my boat today and I have to turn 300 RPM more than I previously did to achieve the same MPH. Can this be remedied with a prop change or am I screwed? My boat also wasn't getting near the same amount of lift as it was either. Is this also a symptom of a different gear ratio?

[John Jackson]

The only ratio's were 1.75 in 99% of them and 1.62 which was an option in the sportsmaster. If you somehow had a 1.62 gear and the new one a 1.75, it would be more than 300 RPMs different, and you would have a lot better holeshot.
I suspect you had the normal 1.75 torquemaster lower and the one you put on was the standard lower unit, also a 1.75. If that is the case, it's also a weaker lower.

[Savage]

Check the gear ratio now, don't assume.

[06 SB]

Here is how to check it.

http://www.bbcboards.net/showthread.php?t=20701

[Jajbs920]

Gear ratio is ok. I ran it today with just me in it and it was running 50 mph at 4500rpm. It's doing something strange. Going to start a new thread. Thanks again for the help.