Real Time Thrust Tests with Complete Boats

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poobought
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Re: Real Time Thrust Tests with Complete Boats

Post by poobought » Fri Feb 03, 2012 9:03 am

fl cracker wrote:cant hide money :lol:

:lol: Well at least we know he had some but maybe not so much now.

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Re: Real Time Thrust Tests with Complete Boats

Post by Waterthunder » Fri Feb 03, 2012 12:18 pm

James I looked up the motor it was originally sold to Garrett in July of 08. So it's almost a 4 year old motor that has now been on three different hulls. Man I doubt a 4 year old 500HP motor can hang with several 600HP motors with dyno sheets and a bigger new supercharged LS motor.
THE PROOF IS IN THE PROP!

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Re: Real Time Thrust Tests with Complete Boats

Post by swamper2 » Fri Feb 03, 2012 12:22 pm

poobought wrote:
fl cracker wrote:cant hide money :lol:

:lol: Well at least we know he had some but maybe not so much now.
http://www.crateenginedepot.com/LSA-62L ... 385C2.aspx price isn't bad depending on how much extras you have to buy to get her running.
16ft alumitech/406sbc/2.38w/3-80in.R's

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Re: Real Time Thrust Tests with Complete Boats

Post by Big Casino » Fri Feb 03, 2012 2:42 pm

Next in our line up of Test Boats:
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Re: Real Time Thrust Tests with Complete Boats

Post by Whitebear » Fri Feb 03, 2012 4:18 pm

Yup. 25% reduction in pitch resulted in 7.99% increase in RPM and 6.05% increase in thrust. I enjoy looking for relationships in performance numbers.

What I get here is the relationship between decreasing pith by 25% and increasing thrust by 6.% its close to a 4:1 ratio, pith to thrust at this throttle setting. It is about 8% increase in RPM and thats about a 3:1 ratio. Fun stuff.
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Re: Real Time Thrust Tests with Complete Boats

Post by poobought » Sun Feb 05, 2012 7:18 pm

Update, Roxy and I finished up the motor swap today on my boat. We test drove it in my swamp and hay field and I'm thinking we will see a pretty big gain in thrust numbers. The motor run flawlessly and felt very strong. And believe it or not it even quieted my Rattletator down ALOT. Now on to getting Roxys New fire breathing Dragon installed.

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Re: Real Time Thrust Tests with Complete Boats

Post by Waterthunder » Wed Feb 08, 2012 11:13 pm

It took awhile but I learned how to quiet them down on the EFI motors you can set them up where there is no clatter. We also used this to get Hamants 4 cyl cont to run smooth.
THE PROOF IS IN THE PROP!

"If you copy someone you will only achieve what has already been done."

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321-508-5316

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Re: Real Time Thrust Tests with Complete Boats

Post by poobought » Thu Feb 09, 2012 8:27 am

Dave, I was very suprised to hear how much the new motor smoothed out my box. It was misarable to drive before and now you can barely hear it. I guess the smoother cam in the motor really makes alot of difference. Its the smoothest carburated motor I've ever driven.

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Re: Real Time Thrust Tests with Complete Boats

Post by Big Casino » Fri Feb 10, 2012 10:20 am

Second to Last Chart from Original Testing:
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Re: Real Time Thrust Tests with Complete Boats

Post by Roxy7430 » Thu Mar 08, 2012 11:05 pm

It is time for an update!

We have done a little more testing and a lot more work!

The 383 Scorpion boat now has a 6.2 Waterthunder, 2:68 rotator and 82" R. This is the same motor that was on the Jimmy White boat on the first round of testing. The main difference is the gear ratio and a more aggressive tune with the MSD ignition box. We did break one rule.........we changed 2 things before re testing.

The BBC Scorpion boat now has a Supercharged LSA motor from Marine Power. The HP rating is almost exactly the same as the BBC at 550. Ratio was 1.91 on the BBC. Changed to 2:38 on the LSA, tested and then changed to 2:68 and tested again. We also used 82" R blades then changed to 82" S blades. (Thank you to Sensenich for providing the S blades for testing purposes)

We also changed the BBC Scorpion from single rear driver, double up front to an air ride suspension with side by side driver and triple up front. Even though the air ride is much heavier the total boat weight dropped just over 300 lbs.

We have the test results for the changes above and just need to get them in a format to post.

We are also going to share some purely subjective "seat of the pants" opinions. Also will have some results of side by side holeshot performance by 3 of the test boats. That part is way more fun than trailer testing!

We are going fishing this weekend.......to much boat building and testing lately!
Jim Allen, President
Go Ballistic Airboat Co
352 463 3960
jim.a@pharma-mgt.com

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Re: Real Time Thrust Tests with Complete Boats

Post by radtech » Mon Mar 12, 2012 11:33 pm

Dang, wish I could get in on this. I am curious about how my boat performs compared to others. I have a 16X8' fiberglass seminole hull with a wore out 220 gpu and a 70" wood prop. I say that only because I know the cylendars need redoing and there was brass bearing shavings in the oil pan when I changed the oil. However, this I have run wide open with other boaters hauling butt down the river and was easily able to stay with them. I'd love to be able to test it against other boats and involve it in what you are doing

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Re: Real Time Thrust Tests with Complete Boats

Post by BUBBA-HAYS » Tue Mar 13, 2012 3:02 pm

any plans on testing an aircraft boat w/ a gearbox?

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Re: Real Time Thrust Tests with Complete Boats

Post by aherr520 » Tue Mar 13, 2012 10:57 pm

BUBBA-HAYS wrote:any plans on testing an aircraft boat w/ a gearbox?
that's what I would like to see ,to compair it to a Carmotor with gearbox,maybe the boat Dan had with the 0470 and stinger on it. it still may not produce the numbers of the high HP CM but I don't think it would be to far off.
aaof member

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ptr34
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Re: Real Time Thrust Tests with Complete Boats

Post by ptr34 » Wed Mar 14, 2012 6:37 am

i have a go520,go470,g0480. two 1.3 to 1 and one 1.5 to 1
if u don't run dry .then should have gotten a bassboat
tons videos on YouTube ptr34

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Re: Real Time Thrust Tests with Complete Boats

Post by flying fish » Thu Mar 22, 2012 10:04 pm

Supercharged LSA motor from Marine Power. Will she catch a fish?
How is the performance of this motor? Does the 6.2 LSA Suprecharged piece got the grunt the BBC had??

Man, I been waiting a week. No, 2 weeks. No wonder it seems so long. :)
15' DB - 6.2 LSA - 4 blade 82" R - 2.52 CH-4

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Re: Real Time Thrust Tests with Complete Boats

Post by Scorpion Airboats » Thu Mar 22, 2012 10:18 pm

Poo-
where and when are you going Sat? The Crown boat is coming up and we want to fish! :old_glory:
Scorpion with WaterThunder fuel injected 550, 2:68 gear box

DANGEROUS LIFESTYLES

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Re: Real Time Thrust Tests with Complete Boats

Post by Roxy7430 » Thu Mar 22, 2012 10:19 pm

The LSA had better thrust numbers than the big block. Sorry for the data delays. Will have some info soon. We also retested the 6.2 thunder motor with a tune up and 2:68 ratio.
Jim Allen, President
Go Ballistic Airboat Co
352 463 3960
jim.a@pharma-mgt.com

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Re: Real Time Thrust Tests with Complete Boats

Post by poobought » Fri Mar 23, 2012 7:38 am

Roxy7430 wrote:The LSA had better thrust numbers than the big block. Sorry for the data delays. Will have some info soon. We also retested the 6.2 thunder motor with a tune up and 2:68 ratio.

Well, come on with your bad self then. Post em up. LOL

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Re: Real Time Thrust Tests with Complete Boats

Post by Roxy7430 » Fri Mar 23, 2012 9:04 am

Latest Test Results: LSA and 6.2 Thunder

LSA: Supercharged 6.2 rated at 550 HP

Ratio RPM 82" Prop 3000RPM WOT
2:38 5200 3 R 430 1449
2:68 5400 3 R 360 1481
2:68 5400 3 S 340 1447

Other: The boat performance was better with the R blades on the water. Holeshot was better and cruise was slightly better and the R was smoother.

Engine: Absolutely flawless. Brand new engine started with the first touch of the starter button - literally. The installation was extremely simple. There were no instructions with the engine and we had no problems with hooking everything up. This was our first experience with a supercharger and EFI. The engine starts with a momentary touch of the starter button....it will turn over on its own until running and if you accidentally touch the starter button while running it will not engage the starter. The engine spools up almost instantly and the throttle is electronic with no hard linkage. You can't make the engine diesel no matter what you do. It starts exactly the same every time regardless of hot , cold or in-between. Fuel economy seems to be about average but more on that later.


6.2 W/T (Carburated)

Ratio RPM 82" Prop 3000RPM WOT
2:68 5500 3 R 350 1382

Other: Notable difference from SBC. Smoother, no diesel, better fuel economy, the gearbox is MUCH quieter. Overall, the same or better in all areas. In owners opinion a very worthwhile upgrade.


Some other details: Our testing is done per our terms. We are attempting to present data in the fairest way possible but there are a few things you need to know. We do at least 3 pulls for every number posted. We post the highest number every time unless we feel that something is not right. For example the LSA pulled 1546 with the 2:68 / r blades. We felt that that number was suspect possibly due to a slightly loose connection so we didn't post that number as it was the only one that high.

When we first started testing we noticed that the first pull was the strongest. We discovered that the tension was not completely releasing and when we zeroed for the next test. What was happening was we were missing the pretension on the system in the next pull making the number somewhat lower. We now ensure that there is no tension after every pull. We now have much more consistency. We also noticed that engine temp can make a difference and we at times will hit a little higher RPM which translates to a slightly higher thrust number.

I am sharing all this for a couple reasons. I want everyone to understand that we aren't "hiding" anything and I also want you to know that the posted numbers are provided in a consistent manor with the same criteria for every setup/pull. The posted numbers are the best we could get out of every boat with the way the owner had set up his boat.

I will share the results for the LSA to demonstrate the consistency norms:
2:68 R blades 5400RPM

Pull 1: 1456
Pull 2: 1481
Pull 3: 1480
Pull 4: 1546
We posted 1481 as the thrust number. This is very typical except for the 1546 number. We felt that there might have been a slightly loose connection. We never hit that number again in any combination in a total of about 20 pulls. Our decision was to not use that number. Please understand that we will continue to make these subjective calls in the future to most accurately share results.

More testing soon!
Jim Allen, President
Go Ballistic Airboat Co
352 463 3960
jim.a@pharma-mgt.com

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skinny99
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Re: Real Time Thrust Tests with Complete Boats

Post by skinny99 » Fri Mar 23, 2012 3:04 pm

"LSA: Supercharged 6.2 rated at 550 HP

Ratio RPM 82" Prop 3000RPM WOT
2:38 5200 3 R 430 1449
2:68 5400 3 R 360 1481
2:68 5400 3 S 340 1447"

A lot of info here for sure. Couple questions.
1) Did you make pulls with the 2:38/"R" turning 5400 RPMS's?

2)Did you make any pulls with the 2:68/"R" turning 5200 RPM's?

3) Did you make any pulls with the 2.68/"S" turning 5000/5200 RPM's?

4) Where were you at in pitch at all these pulls and did you set them with a digital angle finder and if so, where on the blade and what were the number?

5) Do you have dyno sheets on both motors and could we see them?

6) Are you able to track the thrust curve of each combo? Can we see?

Thanks. No doubt a lot of work went into this stuff.
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Re: Real Time Thrust Tests with Complete Boats

Post by Waterthunder » Fri Mar 23, 2012 3:51 pm

The WaterThunder motor is 500HP@5,500RPM's. So by these numbers 50 more Horse power and a blower get you 100lb's more of thrust.
THE PROOF IS IN THE PROP!

"If you copy someone you will only achieve what has already been done."

http://waterthunder.com/
321-508-5316

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Re: Real Time Thrust Tests with Complete Boats

Post by Roxy7430 » Fri Mar 23, 2012 5:14 pm

skinny99 wrote:"LSA: Supercharged 6.2 rated at 550 HP

Ratio RPM 82" Prop 3000RPM WOT
2:38 5200 3 R 430 1449
2:68 5400 3 R 360 1481
2:68 5400 3 S 340 1447"

A lot of info here for sure. Couple questions.
1) Did you make pulls with the 2:38/"R" turning 5400 RPMS's?

2)Did you make any pulls with the 2:68/"R" turning 5200 RPM's?

3) Did you make any pulls with the 2.68/"S" turning 5000/5200 RPM's?

4) Where were you at in pitch at all these pulls and did you set them with a digital angle finder and if so, where on the blade and what were the number?

5) Do you have dyno sheets on both motors and could we see them?

6) Are you able to track the thrust curve of each combo? Can we see?

Thanks. No doubt a lot of work went into this stuff.
1) No. Had a rev limiter that maxed me out at 5200. (took some reprogramming to change that)
2) No. Wasn't as interested in 5200 as I was 5400
3) No. same as # 2 (We also had limited time and it was one or the other) We just couldn't get everything done before it got dark.
4) Pitch is a tricky topic. If you have 5 people look at a particular pitch mark you will get 6 answers! We also found a substantial variation in the pitch marks on each blade for the same prop. I purposely didn't post pitch marks because we didn't feel that we could accurately report the numbers. As I stated in another post there is a SA member that swears that his 3 blade R is pitched over 3, another SA member looked at the same prop and identified it as "maybe 2.5" . I think you get where we are coming from. Generally speaking the W/T engine is at 3 and the LSA is at approx 4 with the R blades as tested. The LSA was on approx the 1 mark with the Superwide.
5) W/T identifies this motor as 500 HP with no dyno sheet. The LSA is identified as 550 HP with no dyno sheet. The difference is that the W/T engine is modified from stock with at least a different camshaft and the LSA is 100% stock internally. The LSA's are randomly dynoed and they do have a representative dyno sheet as I understand it. I have seen the dyno sheet and I think it is on the Marine Power web site.
6) I can graph the thrust curve and save the data in a file. We haven't bothered to do this because the RPM cannot recorded. The thrust curve would be different based on how quickly the operator accelerates.

Hope that answers some of your questions.
Jim Allen, President
Go Ballistic Airboat Co
352 463 3960
jim.a@pharma-mgt.com

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Re: Real Time Thrust Tests with Complete Boats

Post by poobought » Fri Mar 23, 2012 5:35 pm

Skinny, to add to Roxys answers to questions 5 and 6 if we did have dyno sheets and thrust graphs we would certianly share them with everybody. We are working with what we have to work with and hopefully we and everybody else can continue to learn from what we are doing because it is ALOT of work. If anybody wants to have a gearbox and prop changing compitition I think me and Roxy can take you. :lol: :lol:

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Re: Real Time Thrust Tests with Complete Boats

Post by skinny99 » Fri Mar 23, 2012 11:32 pm

poobought wrote:Skinny, to add to Roxys answers to questions 5 and 6 if we did have dyno sheets and thrust graphs we would certianly share them with everybody. We are working with what we have to work with and hopefully we and everybody else can continue to learn from what we are doing because it is ALOT of work. If anybody wants to have a gearbox and prop changing compitition I think me and Roxy can take you. :lol: :lol:
I very much understand how much work y'all are doing. It is a chore I am sure. I am a racer to the core and have spent a lot of time testing, collecting and evaluating data. I know there are some very general and specific answers out in the work y'all have done.
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Re: Real Time Thrust Tests with Complete Boats

Post by skinny99 » Fri Mar 23, 2012 11:50 pm

Roxy7430 wrote:
skinny99 wrote:"LSA: Supercharged 6.2 rated at 550 HP

Ratio RPM 82" Prop 3000RPM WOT
2:38 5200 3 R 430 1449
2:68 5400 3 R 360 1481
2:68 5400 3 S 340 1447"

A lot of info here for sure. Couple questions.
1) Did you make pulls with the 2:38/"R" turning 5400 RPMS's?

2)Did you make any pulls with the 2:68/"R" turning 5200 RPM's?

3) Did you make any pulls with the 2.68/"S" turning 5000/5200 RPM's?

4) Where were you at in pitch at all these pulls and did you set them with a digital angle finder and if so, where on the blade and what were the number?

5) Do you have dyno sheets on both motors and could we see them?

6) Are you able to track the thrust curve of each combo? Can we see?

Thanks. No doubt a lot of work went into this stuff.
1) No. Had a rev limiter that maxed me out at 5200. (took some reprogramming to change that)
2) No. Wasn't as interested in 5200 as I was 5400
3) No. same as # 2 (We also had limited time and it was one or the other) We just couldn't get everything done before it got dark.
4) Pitch is a tricky topic. If you have 5 people look at a particular pitch mark you will get 6 answers! We also found a substantial variation in the pitch marks on each blade for the same prop. I purposely didn't post pitch marks because we didn't feel that we could accurately report the numbers. As I stated in another post there is a SA member that swears that his 3 blade R is pitched over 3, another SA member looked at the same prop and identified it as "maybe 2.5" . I think you get where we are coming from. Generally speaking the W/T engine is at 3 and the LSA is at approx 4 with the R blades as tested. The LSA was on approx the 1 mark with the Superwide.
5) W/T identifies this motor as 500 HP with no dyno sheet. The LSA is identified as 550 HP with no dyno sheet. The difference is that the W/T engine is modified from stock with at least a different camshaft and the LSA is 100% stock internally. The LSA's are randomly dynoed and they do have a representative dyno sheet as I understand it. I have seen the dyno sheet and I think it is on the Marine Power web site.
6) I can graph the thrust curve and save the data in a file. We haven't bothered to do this because the RPM cannot recorded. The thrust curve would be different based on how quickly the operator accelerates.

Hope that answers some of your questions.

As far as 1,2 and 3 go I understand how much time and effort y'all have went througHh.

#4 I very much agree that the marks are very subjective. It is not a dick measuring contest, really it is just an experiment. Do you not think that a digital measurement of the tip angle of just the "R" blade would be a consistent gauge of pitch. It would help you be able to reproduce your numbers easier I think.

I know what I have measured what 2,2.5 and 3 measure like at the tips of an "R". I won't post cause I don't want a pissing match to insue. However it has been pretty consistant between blades.


#5,6 I am not really looking at an acceleration curve more just a chart of thrust per RPM's. If you wanted to do someting like charting one of the motors from idle to WOT at 200 RPM increments. Then test the combo from 4800 at WOT to 5600 at WOT in 200 RPM increments. That would be some very interesting data, especially if you could overlay it with the torque and horsepower curves.

I may be unrealistic in my wants but I believe that is where the real answers lie. Thanks
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