Re: Stingray 20' Prop Issue
Yes, everything you said makes total sense and confirms my guess that the 23 pitch you're running is completely wrong. Ironically, you and I happen to have nearly identical boats....mine is a 1999 200LX with 5.0...but mine is a Volvo (meaningless...both are Vortec Chevy 305 small blocks and have similar gear ratios)...and I have converted to a 4 bbl carb and some other light mods that have upped my HP output by probably 30 hp over stock.
And despite my having a bit more HP than yours, mine could NEVER push a 23 pitch prop. And your 4100-4200 answer and dog-outta-the-hole response confirms that yours cannot either. You are not even getting near the peak HP output of your motor if you're spinning it that slowly.
Your motor is supposed to be in the 4,400 to 4,800 range. Closer to 4,800 is better IMO because you want strong holeshot. At 4,100/4,200 I fully expect you'd be extremely doggy out of the hole.
You are way overpropped with that 23 pitch. Not sure why it's on that boat as it has never belonged there. I'd suggest you drop down to a 19 or 20 pitch prop. 4 blade might help even a little bit more with your porpoising and will definitely help with your holeshot.
If you want to stay aluminum, try the Solas Amita 4 blade 19 pitch. Probably can be found in the $150 range. If you're looking to spend more on stainless, Solas also makes a prop called the HR Titan, $300+. I'm told Stilletto makes a nice Stainless 4 blade in a 20 pitch, I've never tried it. But I believe any of these will get you in your proper RPM range. I'll steer you toward the Solas only because that's what I run, and I have same boat as you, and I know for a fact it works. Mine has been repitched to a 20 by a local prop shop, but that was to accomodate my extra HP from minor engine mods. I really believe a 19 pitch 4 blade Solas (Alum or Stainless) would work absolutely perfect on yours.
And with any of above, I think you'll be STUNNED at the holeshot you gain, and I bet your top speed stays about the same as it is now...might even improve a bit. Porpoising might improve a bit as well, but you'll still need to keep it trimmed all the way down at most slower speeds. FWIW mine gets on plane in about 2 seconds, and will go zero to thirty in less than 4 seconds easily. And my top speed about 58 mph GPS. I assure you that none of this is an exaggeration...wish I could take you for a ride but I'm in Indiana...
Most of that excellent performance was accomplished by propping correctly, and not-so-much by my 4bbl carb/engine mods. You'll probably be closer to 55 mph GPS with your factory engine setup on most of those props, and it'll rip outta the hole like you can't imagine.
Reprop correctly first, then see how your porpoising is, before you decide you need to mess with Smart Tabs or Trim tabs. You will still need to leave your trim all the way down for most speeds between zero and 35-ish....that's the nature of these Stingrays and is not considered abnormal. You'll only start trimming out a bit at 35-ish and faster.
