Hydrofoil are great for some boats and pointless on others. getting on the plane at slower speeds can save a lot of money on fuel but as others have said they do drop top end speed. Boating is about how you use the boat and finding the best solution and hence they do have their place but boaters agree that they have negatives as well as some positives.
hydrofoil | make a difference with hole shots, and for pulling tubes, skis,etc
Adding a hydrofoil to an outboard - Yes or No
Negatives and positives
These are great when you want to cruise at slower speeds or you boat is underpowered but then is not often the case with RIB owners . They are great though for fishing boats where the mark is a long way and they want to conserve fuel and I have seen the planing speed drop by 4-5 knots so impressive results.
Starfire Hydrofoil - Force 4 Eliminates porpoising, cavitation & chine walking
In all situations they did a great job. If the engine is running at optimum trim they will lift the aft end, slower planning speeds and on the s3.45 stopped chine riding. You may loose 1 or 2 kts at wot but in reality, how much time do you really sit at full chat.
If you are concerned it will not plane towing at slow speeds - considering a hydrofoil
A hydrofoil can help as well as trim tabs. A cheaper options of trim tabs are SMART TABS SX – TRIM TABS by Nauticusinc.
Not only do they help with launch but they really help slow speed tracking as well.
Trim tabs stalled on 1988 Bayliner 1950 Capri 19 1/2 ft. 3.0 omc.
TRIM TABS makes you able to cruise on a lower speed and helps to keep boat stable. Trim tabs work very well for slow planing. Save money on fuel and make your boat handle much better. They are expensive, but worth.
In low speeds
You can add your hydrofoil in order to obtain slower speeds without comming off plane in tricky treed areas. It also helped with getting in boat without swim ladder. If u normally run bow lifting prop it helps with ski and water sports to get bow down faster. Otherwise if planning water sports a lot I change prop for more low end torque and hole shot. So yes they work but for high speed and fishing not needed they can tend to get tree snagged when trolling.
"I had a Chris Craft 19 ft. with a 5.0L engine several years ago that would just rear up when I added full throttle. The bow would stay way up until the boat gained some speed, then the bow would come down and the boat would come up on plane. This was due to the weight of the engine and fuel in the stern of the boat. I bought a Stingray hydrofoil, installed it, and the boat would come up on plane immediately when adding full throttle. I just bought a 2001 Crownline 180 BR with a 5.7L engine. I installed a Stingray hydrofoil and again, it solved my problem."
But if you are travelling at slower speeds, the whale tail will definitely improve performance and allow the boat to come up on plane quicker and at slower speeds.
"I have a whale tail. My boat bow doesn't rise unless I use the trim button which I find useless since I can get on plane fairly quickly without trimming. But then again my boat only has a 3.0 and top speed of 38mph. I pull a tube at anywhere from 15mph when the kids are riding and around 25mph when the adults are riding. Anything over 25mph and it's just a disaster waiting to happen especially if the water is choppy. Seen and heard of too many acl tears, spinal injuries, broken bones etc when traveling 30-40 mph while riding the tube. Especially if there is more than one rider because people sometimes collide with each other when flipped off the tube. That's me on the left flopping like a crash dummy last year with my brother on the right who you can't really see. And this was at about 25 mph but we were being slung to the left of the boat at the moment which dramatically increases your speed."
Never run with drive tilted up for trimming you can damage the tilt lock mechanism which on your is almost obsolete.
The hydrofoil should help getting on plane. Your engine small and not very powerful. So fast hole shots will never happen.
Or you can install trim tabs. They make auto adjusting ones for small boats like yours. Or you can get the electric or hydraulic ones.
All depends on your budget.
A little trick to faster plane is to flip the trim insert to the forward position.
From factory they will be set in the aft position but you will need to set them in the forward position for the best planing and performance speed.
This just trims in the drive deeper into the water letting the boat plain faster and easier. The extra half inch just helps the boat get more water under.
The right height the anti cavitation plate
Get rid of the hydrofoil if motor is at the right height the anti cavitation plate on the lower unit should have no water on top of it while on plane. Thus the hydrofoil is doing absolutely nothing. Evidentially running under the water causing the bucking.