2001 Sprint 289 pad-to-prop adjustment

[Deude_Mann]

My pad to prop height is large at 5.5" and I am thinking I need to reduce it by a lot. I'm looking for others experience here with the steeply stepped nature of this hull. BTW I have also posted this in the Sprint forum but this hull is a little unusual and there is not much traffic over there.

Background:
I have a 2001 Sprint 289 F&S which is approximately a 19' boat with a Merc XR6 150. The prop is freshly refurbished and is sized correctly; at WOT the boat runs at 5400-5600 RPM trimmed.

Since I bought the boat the steering has been heavy even after replacement of the steering cables by a well regarded boat shop. It is heavy from hole shot to plane even with judicious adjustment of the trim.

I am checking the pad to prop height. And much to my surprise it is a LOT at 5.5". I used the normal procedure to make the measurement: Hull and cavitation plate leveled. Measure from prop shaft center to ground and from pad to ground. Subtract the two measurements.



Question:
5.5" seems like a lot of prop-to-pad distance so I want to raise the motor on the transom. But how high for this hull? I do not have a jack plate but right now the motor mount is set on the topmost hole on the transom bolts. Or put another way, the motor is as low as it can go on the transom.
The holes are 3/4" apart so that is the adjustment increment. That gives me four reasonable options:
Raise it 1X holes to 4.75" pr-to-pad (not enough IMO)
Raise it 2X holes to 4.0" pr-to-pad (maybe enough)
Raise it 3X holes to 3.25" pr-to-pad (approx the standard recommendation for most boats)
Raise it 4X holes to 2.5" pr-to-pad (this is getting a bit sporty but may be OK given the 12" transom setback from the pad - see second post)

I will note here that I HAVE A WATER PRESSURE GAUGE and watch that while running. I'll add water inlet scoops if need be to make sure I have enough water pressure. The water pump itself was just replaced.

I have read through all the info here but there is not much on this specific Sprint hull if anything. Also note in the photo that the rear of the hull has two deep steps and thus the motor is actually well back of the effective pad by at least 9"; this acts like a jack plate in that regard.

Thanks in advance all

[Deude_Mann]

Click here for a photo of the pad, steps, and transom. The low photo size limit here really screws up the detail so I hosted it remotely.

[Commanchejoe]

I would take it to around 4" to start with and go up in 1/4" increments

[CB_SabreFTD18]

I had a 221 back in the day. 12” manual jackplate. Also, I had a 262 & 277 prior. If you could add 4” manual plate, it would make things easier. 3.5-4.0 prop to pad should fine. FWIW, various props give more steering torque than others regardless of engine height. All tend to get tighter as you raise engine near max for the prop. 4 blades usually have more steering torque than 3 blades. Larger the diameter, the more steering torque at higher engine heights, generally. Smaller diameter props worked well for me in all those light hulls up to the small block 200. An old small diameter Laser 2 ran very well, but even that small prop did have noticeable torque. If you don’t have hydraulic steering, installing it would help tremendously. A small barrel Trophy prop ran well on those boats too. If I recall, on the 277 I had a cheaper “rapture” prop on it. It was 13 3/4 dia I think. It ran fine with it as long as I didn’t raise the engine too high to create slip in turns. Powertech makes a bunch of smaller props that would work if you decide to prop shop around that don’t cost an arm & leg.