Whats the lowest powered STV that you have ever seen?

[JPEROG]

As the title says, I picked up an STV Pro Comp for my son as his next step in boating. I am going to rig it with the same 15" 115 optimax that he had on his 15' wahoo. Any idea what it should run with 2.33 and a 5750 limiter I know it won't be too crazy. His wahoo ran a best of 60 and my first pro comp with a carbed 200 ran 94 at 7K with a 1.87 turning a 30 chopper worked by Tillman (30 years ago).

Joe

[99fxst99]

I will guess about the same. My concern would be that the 115 wont make enough power to get enough air under the boat to overcome the drag of the hull and sponsons being fully immersed.
I am thinking of a good first boat for my 12 yr old. He is already a capable operator, and we are working on his boater's license at this time.
I wish I still had my 18 Talon to put a smaller motor on for a first performance boat. Keep us informed on how this project goes.

[JPEROG]

The good news is that he only weighs about 100 lbs so we will see. I have to clean up the rigging and make some changes before we hang the motor. It will be a couple weeks before its wet.

Joe

[kellytheaker]

Joe sounds like an exciting project for a father/son . I have seen your rigging sooo it will be interesting to see the finished hull with your input. I would suspect an improvement in speed . I think you will have a pretty trick tunnel seeking out 75 but looking like 90 . Have fun - whenever I hear of these projects supposedly for the kids - I always look at the parent and you realize it' for both of them in reallity . Those hulls are super neat just sitting still .

[JPEROG]

Well, its truly for him but it wouldn't happen if I wasn't here for sure. Don't get me wrong, I love seeing young guys get involved in our hobby and watching my son expand his experiences-its just much harder for them then it was in the 80s when I did it. I remember going into my credit union at 16 "with my dad" and getting a loan for a new motorcycle in less then 15 minutes-those days are history for young guys and if they have the cash then its the liability cost that stops them next. I am having a hard time insuring this pro comp with a baby motor as a fifty year old adult, yet when I was 18 they insured me on my first STV with no issue (there is some truth to "the good old days").

438770438771

Joe

[Euroski]

Average Euro with 200 may break 90. But have no idea with 115.

[David - WI]

If you just plonk a 100# driver and 115 Opti on a 19' Euro that was already entered into the Tunnelboat simulator, you get 63 mph top speed... for what it's worth.

[Capt.Insane-o]

Gear ratio is the killer. The 115 and 125 2s had a 2.07 might be worth looking into a swap later

[PaulR]

My nephew had a Euro with a mid 1980's 150 Merc on it. It ran 70-75 but that's right where it wanted to pack air so it hopped on the top end unless you headed into a stiff wind on some chop. My Drag motor is down right now so I think I'll put my 135 2L powerhead on my rocket and see if I can get 60 out of it! LOL!

[JPEROG]

I have a 200 waiting but I need to restrain myself and make him learn the characteristics of crossing wakes and stepping over them when he comes up on someone to pass ect. I told his mom that the 115 would stay on it for a year.

https://www.screamandfly.com/image.php?u=83&dateline=1482609378 (https://www.screamandfly.com/member.php?83-Capt-Insane-o) Capt.Insane-o (https://www.screamandfly.com/member.php?83-Capt-Insane-o)
https://www.screamandfly.com/images/statusicon/user-online.png Spring! https://www.screamandfly.com/images/reputation/reputation_pos.png https://www.screamandfly.com/images/reputation/reputation_pos.png https://www.screamandfly.com/images/reputation/reputation_pos.png https://www.screamandfly.com/images/reputation/reputation_pos.png https://www.screamandfly.com/images/reputation/reputation_pos.png Gear ratio is the killer. The 115 and 125 2s had a 2.07 might be worth looking into a swap later
--
We have a set going in it now.


Joe

[JPEROG]

If you just plonk a 100# driver and 115 Opti on a 19' Euro that was already entered into the Tunnelboat simulator, you get 63 mph top speed... for what it's worth.

My original guess was 65 which will be perfect. I think that a big ear chopper or an ET is going to give him the ability to trim it up and learn at a reasonable speed.

Joe

[mach351]

I ran an Xr6 150 for years on my STV. Best speed was 110, but it would run upper 90’s everytime it went out. We also rigged a mirage ski racer with a 2.0 150 and it went 96. Never messed with anything smaller than a V6, but I agree rpm is going to be your issue. Gunna need a bunch of pitch.

[XstreamVking]

Wasn't there a vid of an stv with a 150 4s honda on the web? A 115 opti with a small blade 24p trophy should go at least 60.

[JBS]

I'm thinking 60s too?

[home made tunnel]

Wasn't there a vid of an stv with a 150 4s honda on the web? A 115 opti with a small blade 24p trophy should go at least 60.

Yes there was, but that guy with the Honda had a crappy prop, and I think it topped out at like 30mph haha.

If your son does 65mph with that boat, that's great. I'm lucky to hit 65 in a headwind with chop with my little 500lb tunnel with a 115 Pro XS on it. 23p through hub cleaver, 2.07 gears. And mine's hopping on the top end.

[KG4]

I seen a video of a stv or mirage with a 150 inline and it was flying.I think it was in Mexico.

[Hot Shot Merc]

50mph:thumbsup:

[Krazymaan]

After the boat, does he get the 69 Camaro when he's 18?

[JPEROG]

After the boat, does he get the 69 Camaro when he's 18?

Hes an only child but cars are not really my thing unless its something that we would get into together. Boating forces time spent together and created great memories for me that will never be erased. All every parent wants for their kid is more then what they had...

Joe

[Krazymaan]

I thought maybe you had a 69 camaro under the car cover next to the STV. By looking at the rear quarter panel body line.

[JPEROG]

I thought maybe you had a 69 camaro under the car cover next to the STV. By looking at the rear quarter panel body line.

Thats a hellcat "family car". But its not mine.

Joe

[Chaz]

Boating forces time spent together and created great memories for me that will never be erased.
Joe

And those frustrating times when you think he's not paying attention or "just not really into it". It's just a momentary thing in their life they have to figure out. It might take ten years for him to say so, but it will dawn on him as it has for my son that you were there at his side for all of it.


Tell Cory I said "awesome whip dude" .. or whatever they say these days :thumbsup:

[David]

We had a 115 HO Etec on a pair of boats. 67 on a 16' Baja with a big prop. 64 with a more useful prop. Then we put the 115 on a 19' flat bottom ski boat (J Craft). 52 with a big prop, 47 with a ski prop. My guess is the STV won't be as fast as the Baja, but a lot faster than the ski boat.

[Capt.Insane-o]

Simon could move the limiter...but thats kinda spendy

[JPEROG]

Simon could move the limiter...but thats kinda spendy

You think its safe to turn it 62 or 64 for extended periods? I can get the box bumped but I want it to live and not go past its power curve. We had the little whaler set up to run 5720 on the smartcraft and it stayed there for 30 miles at a time. The 2.07 will help a little bit as well.

Joe

[eli]

Back in the earily ,70,s I was 13 ,if your boat went 50 you were king ,I got my 14 , alumna craft up to 28 with 10 hp Omc , my cousin went 30 with 9.8 merc on 12 , alum a craft ,so one day we decided to put both motors on the 12 footer , and each steer with tanks in the front we almost lost it and our parents were mad ,I think we never made to 30 mph and if we had I think we would of been upside down ,so joe is doing it right to get sons feet wet before the real speed come along

[Capt.Insane-o]

Back in the earily ,70,s I was 13 ,if your boat went 50 you were king ,I got my 14 , alumna craft up to 28 with 10 hp Omc , my cousin went 30 with 9.8 merc on 12 , alum a craft ,so one day we decided to put both motors on the 12 footer , and each steer with tanks in the front we almost lost it and our parents were mad ,I think we never made to 30 mph and if we had I think we would of been upside down ,so joe is doing it right to get sons feet wet before the real speed come along

Well if he was a real dad he would put him in a center steer viper with a 150 and a 28 chopper with the nose cone pointed at the drain hole. ;)

[Scream And Fly]

I remember somebody clamping a 9.9 Merc on a Mirage, and if I recall, it ran on plane too!
JPEROG great post Joe and I love that Pro Comp!

My first fast boat was a Vector with a 140 Mariner inline-6. I had money saved from my after-school job of being a bicycle assembler at Toys R’ Us. That was when I was 16 and I was on top of the world. I remember that feeling of just being in the coolest boat ever. I think it ran like 65mph at best but that was perfectly fine for me. It had a huge impact on my life. Nothing really ever matches those first incredible feelings of owning such an awesome boat.

[Capt.Insane-o]

I remember somebody clamping a 9.9 Merc on a Mirage, and if I recall, it ran on plane too!
JPEROG great post Joe and I love that Pro Comp!

My first fast boat was a Vector with a 140 Mariner inline-6. I had money saved from my after-school job of being a bicycle assembler at Toys R’ Us. That was when I was 16 and I was on top of the world. I remember that feeling of just being in the coolest boat ever. I think it ran like 65mph at best but that was perfectly fine for me. It had a huge impact on my life. Nothing really ever matches those first incredible feelings of owning such an awesome boat.

439605

[mikesufka]

^^^ Great pic !

MDS

[MattGreen]

439605

That poor guy is probably waiting on his 2.5 block from Ron at MAG Machine, you could update the meme lol.

Matt

[JPEROG]

Well after going through this old pro-comp and making what I consider to be a good looking old rig for my son, we finally hit the water with it today. The boat ran 73 on the limiter "bumped to 6200" with a 26 four blade. It jumps on plane with the motor high (I made an educated guess on height) and it ended up being perfect so we never made an adjustment but as soon as he touched the jackplate it dropped pressure and went into guardian. We will try a 28 and a couple of worked 30s tomorrow but my new goal is 80--I was originally thinking 70 was a stretch.

This has been another long project but Kory and I are both happy with the results.

465857465858465859465860465861465862465863465864465865465866465867

Joe

[Capt.Insane-o]

That's awesome.

[JBS]

That's a respectable speed for that set up.

[Baja170]

Yes there was, but that guy with the Honda had a crappy prop, and I think it topped out at like 30mph haha.

If your son does 65mph with that boat, that's great. I'm lucky to hit 65 in a headwind with chop with my little 500lb tunnel with a 115 Pro XS on it. 23p through hub cleaver, 2.07 gears. And mine's hopping on the top end.


Your little tunnel is super cool though and gorgeous!!

[H2OPERF]

Love the black wrap around... Did you spray it with clear polyurethane/buff, man it really looks good.

[Beak Boater]

Great story....love to see the youth exposed to things, whether its boats, cars, or motorcycles in a safe progressive way. Let them decide if its for them.

[Rodney Nance]

There is hope yet.

[scawd the dog]

Great set up Joe - Cory has to be stoked !

[JPEROG]

Love the black wrap around... Did you spray it with clear polyurethane/buff, man it really looks good.

The wrap around was done by Randy "Wildman" and yes he cleared it afterwards. He had the entire boat buffed by Brandon "a detailer that rents a shop from Randy". It looks a good or better then the day it was built in 92'.

Joe

[JPEROG]

Great set up Joe - Cory has to be stoked !

Brent,

Its so cool to see him with such confidence. Hes not intimidated by it at all and it will be a great platform for him to learn the ins and outs of running with us as a group with different water conditions and traffic. By the way, the Allison is ready for you and Blake anytime.

Joe

[JPEROG]

So with a 30 lighting et at 6000 with my 205 lb butt in the boat it ran 6000 at 73 mph. With Kory by himself its on the limiter at 77. We are going to run a 31 Bblades Blaster (four blade) and see what he gets. I never expected this from a little opti. It is a small case and a small skeg (we are going to add a torque tab and 3/4 of an inch to the depth of it).

Joe

[MorganBucks]

Cool Rig, Safe Boating!

[Radiant]

Very Cool.

I like the 75 hp decal on the cowling.

[David]

Does it porpoise?

[Capt.Insane-o]

I wouldn't weld on that skeg and if it's not ill handling adding tab to the skeg is just going to slow it down.

[JPEROG]

Does it porpoise?

Absolutely zero. I will get video of it soon. We got lucky that it does everything right.

Joe

[Jimboat]

STV Pro Comp with 115 optimax. Any idea what it should run with 2.33 and a 5750 limiter. Joe
Hi Joe - when i do a quick check using "Tunnel Boat Design Program" software (https://aeromarineresearch.com/tbdp6.html), using my STV model and 100lb driver and 115 optimax engine (no other details, sorry), i get top speed 74mph. maybe this helps? (naturally the results depend on actual setup, so used a 'middle-of-the-road' hull setup to get a 'quick' check on possible speeds).

[FUJIMO]

...Kid's Nowadays...I'll Tell Ya...They Are Sooooo Smart...lol...https://scontent-mia3-1.xx.fbcdn.net/v/t1.0-9/16864773_1300501730043031_1364805673839368026_n.jpg?_nc_cat=111&_nc_sid=2d5d41&_nc_ohc=dDfMGXyJd9YAX-68Bjb&_nc_ht=scontent-mia3-1.xx&oh=3be4d2996b3c335d995ce545795203f5&oe=5EEBC3A1

[rock]

Good job Joe. nice rig.

Rock

[Mad Maximillion]

Sweet rig!

[JPEROG]

Hi Joe - when i do a quick check using "Tunnel Boat Design Program" software (https://aeromarineresearch.com/tbdp6.html), using my STV model and 100lb driver and 115 optimax engine (no other details, sorry), i get top speed 74mph. maybe this helps?

Your model is very close. He clicked of four 80 mph passes this morning with a 31 Bblades Blaster at 6100. Remember this is now a 2.07 gear in place of the stock 2.33, the limiter is at 6250 instead of 5750, its a modified 15" midsection that can blow its breath, it is a small case, small skeg, and the motor is high. Bottom line is that I never thought it would have the capability that it does.

Joe

[Jimboat]

Your model is very close. He clicked of four 80 mph passes this morning with a 31 Bblades Blaster at 6100. Remember this is now a 2.07 gear in place of the stock 2.33, the limiter is at 6250 instead of 5750, its a modified 15" midsection that can blow its breath, it is a small case, small skeg, and the motor is high. Bottom line is that I never thought it would have the capability that it does.Joe
good job, Joe! sounds like we tested the same boat! i'm sure that if I input your actual hull weights and setup changes, that the TBDP (https://aeromarineresearch.com/tbdp6.html) would accurately align with your water results. Your hull design is very sensitive to setup, power and weights, especially at lower speeds. You're getting great performance of that engine!

[baja200merk]

I told you that thing was gonna go 80 :D. Looks great!