Speed difference on Mercruiser 228

[79Merc80]

Hello experts.

Just a quick question. The PO of my boat put an inline 6 upper drive (Without changing gears). At 3k RPM, I am getting 31 MPH. I just aquired a drive from a MerCruiser 233. What kind of speed difference can I expect at 3k RPM???

Thanks in advance, Craig

 

[Bondo]

Hello experts.

Just a quick question. The PO of my boat put an inline 6 upper drive (Without changing gears). At 3k RPM, I am getting 31 MPH. I just aquired a drive from a MerCruiser 233. What kind of speed difference can I expect at 3k RPM???

Thanks in advance, Craig

Ayuh,.... 31 mph at 3000 rpms is fine, but what are yer numbers at Wot,..??

I suspect you'll be luggin' the motor, severely, with the 233 outdrive ratio,....

 

[79Merc80]

I don't know what the number are at WOT, I haven't had it that far. It's a 19P stainless 3 blade and highest I have had it was 47 MPH at 4500 RPM. I thought the 228 came with a 1.47 ratio.