Newbie: Smart Tabs / 4 fin prop / Hydrofoil on Reinell 190BR 4.3GL Volvo Penta SX I/O

dcolemanca · May 8, 2012

Its a standard 2004 19ft open bow run about boat, V hull, dry weight 2450lbs, used exclusively on lake, sea level.

I have read many threads on this topic and sure the right approach depends on the type of boat and what the goal is.

Its my first boat and overall have been satisfied with performance. However I woudl like to address the issues that many other pleasure boaters seem to have: slow getting onto plane with significant bow lift, minimum planing speed too high. The latter is the most important as we have young children (10 and 12) and want to do fun stuff like tubing and knee boarding and then progress to water skiing and wakeboarding. So we basically want to widen the usable speed range, willing to accept some drop on top speed, great if we can improve fuel economy.

The other weekend I found myself staring jealously at another smaller boat pulling a skier on the plane, guessing they were going about 15 mph, as I zoomed passed about 25 unable to slow down very much without dropping off the plane.

I know I need to get better at trimming the boat but think some extra help needed.

I see a lot of varied opinions on hydrofoils and most people recommending Nautilus Smart Tabs SX instead. I also see that moving to 4 fin prop (from the standard 3 fin prop, not sure on pitch etc) would improve handling too.

For this kind of boat what would work best to what I am trying to achieve?

Would a combination of smart tabs and 4 fin prop work best or is it overkill?

What is general rule of thumb on propeller fin pitch and diameter when going from 3 fin to 4 fin propeller?

Philster · May 8, 2012

Re: Newbie: Smart Tabs / 4 fin prop / Hydrofoil on Reinell 190BR 4.3GL Volvo Penta SX

A combination of Smart Tabs and a 4-blade prop would be the best combo and not overkill by any means.

What prop is on there now? To move to a 4-blader, you step down in pitch by 1. If you have a 19P, 3-blader, step down to a 18p, 4-blader and add tabs. This is the way to improve everything on the low end.

Adding a hydrofoil is ill advised, unless you have some sort of frankenstein outboard or something. They can be good in oddball situations -- not on your boat.

Maclin · May 8, 2012

Re: Newbie: Smart Tabs / 4 fin prop / Hydrofoil on Reinell 190BR 4.3GL Volvo Penta SX

Learning how to trim is the first step, and it is "free" as well. Start out all the way down until it begins to plane then gradually trim up, but not a lot if you are wanting to stay at 20mph or so. I do not trim up much until I plan to go on up to 25mph or so. Each boat is a little different, some boats get a lot of bow-steer from wave action if the trim is down past certain speeds. You may also need to move passengers or gear around from the back to the front as a lot of weight in the stern makes the planing speed higher.

Some take off fast and hit 25 or so then thottle down slowly and adjust trim back down, sometimes this helps find the sweet spot or technique to use for a particular boat and load. Can be a little scary for younger tube riders for a few seconds, but can be part of the fun also.

Tabs on the hull are beneficial to most boat hull designs regarding time to plane and low maintainable planing speeds. The hydrofoils push in the wrong spot regarding leverage, pushing only in the middle of the hull is not as stable as at the edges.

Some props provide lift, and some props are designed to keep lower planing speeds also, like some 4 blade designs. You may want to post the prop questions over in the Prop topics section, lots of expertise there.

The tabs provide more planing surface. May not seem like much but it is behind the stern and that helps the balance boat from stern to bow also.

Regarding tabs, typically on 20 foot or less boats the hydraulic tabs are overkill, mainly because those will need to be adjusted by the operator for each cruise situation, and each time the boat stops and starts. On larger boats they are almost mandatory, but on the smaller boats the automatic ones like Smart Tabs make more sense, as they are set and forget.

Another real help in obtaining and maintaining slower planing speeds are DuoProps. Kind of an expensive upgrade but man do they make a difference.

Maclin · May 8, 2012

Re: Newbie: Smart Tabs / 4 fin prop / Hydrofoil on Reinell 190BR 4.3GL Volvo Penta SX

Good stuff as usual Philster! Your post was not there yet when this old man started composing...

Oshkosh1 · May 8, 2012

Re: Newbie: Smart Tabs / 4 fin prop / Hydrofoil on Reinell 190BR 4.3GL Volvo Penta SX

Smart tabs are the way to go...as stated before a real "Ron Popeil" item..."set it and forget it"! They're also inexpensive and can be installed in an hour(if you're slow).

The 4.3 would do well with either a 19P 4blade or 21P 3blade for your situation.(edit...was thinking of my current motor, not my previous boat...hope this isn't a sign of things to come!)

IMO the "Tuna tails" are a waste of money, not to mention the fact that they're hideous and require you to drill holes into your drive.

Oh...also, correct weight and balance of your coolers, gear and passengers will also effect change in the ride. I've expiremented with moving both to the bow area/seats when tubing, skiing etc...It's amazing how much moving one kid(or heavy coolers/anchors/other "stuff") to the front will change the bow lift, especially with the excess drag of a tube, kneeboard, or skiier!

dhof55 · May 8, 2012