Hydrodyne 18 I/o prop

[iand464]

I have an old hydrodyne 18 with the 888 It is a good running boat I got without an out drive. I had a R drive in good shape from a 470. So that's what I have. I have the wrong gear ratio out drive on it, it should have a 1.5 and I have 1.84. I can turn my stainless 22 pitch 3 blade to about 46-4700 rpm. I need to loose about 4-500 rpm. i don't want to buy new gears or another stainless.

What is the highest aluminum pitched prop?
Would a four blade 23 take out that much?
Could a prop shop get some more pitch out of my 22?

We mostly drive out to islands to go swimming, but do some skiing tubing and wake boarding. I can pull the great big tubes and multiple skiers easily the way it is, just don't like it so much past the recommended rpm.

 

[Bondo]

Ayuh,.... Is it the 302 motor, or the 351 motor,..??

Either of 'em can turn the rpms yer seein',..... 4100/ 4200 rpms is gettin' pretty low for Wot,.....

Generally speakin', 23" is 'bout as big as aluminum props get, though Ya occasionaly see 25" pitch aluminum props,.....

A prop shop, oughta be able to beat in another inch into the prop ya got, along with addin' more cup, to bring down yer rpms,....

 

[iand464]

It's a 302 with 351 heads on it. It has the 351 firing order too.

Sounds like leaving it alone may be a good option