Thanks for the info Frank A.

pnwboat

Rear Admiral
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Oct 8, 2007
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Just wanted to say thanks for your tip Frank A. for information regarding changing the 1988 125HP 1.73:1 lower end to a late eighties 2:1 85HP lower end to increase performance. Did exactly that a week or so ago on my 1988 Bayliner Cobra 18.5 w/125HP. With the original lower end, 17p stainless I was turning 5100 RPM's WOT at 41 MPH. Put the 2:1 lower end on and what a difference it made! RPM's shot up to 6000 at 42 mph WOT. The hole shot was really surprising! Today I put a 19p stainless and dropped the RPM's down to 5600 WOT at a little over 45 MPH. With the original lower end, I could not run a 19p prop and get decent performance. The 125HP motor really likes that 2:1 ratio lower end. I highly recommend the lower end swap. It's like I have a different engine now.

Maybe that's why the later model 120HP's use the 2:1 gear ratio.....
 
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