The Game Changer

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Davie GSO480
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Re: The Game Changer

Post by Davie GSO480 » Wed Jun 26, 2019 5:22 pm

CarMotorBarge wrote:
Davie GSO480 wrote:It is what it is...it aint a full racer, but it is a fun boat to ride, performs amazing well, snaps hard.
Remember its about 20% displacement disadvantage to a 0 540
Those thrust numbers were on tester, not a boat.....No cage etc in the way.
The 3 blade Alpha is the only prop we tested that work in the higher rpm band, the Saber stopped converting about 3100,,,,,

https://southernairboat.com/gallery/#
I posted a couple pictures on main gallery
You need to change your user name. I aint changing the name, when I joined this site way back I had a Lycoming supercharged 480 ci. Me and Mike Thruman fixed up alittle. Heck id be called PE 90, 0540, gso480, up stack etc,,,,never mind trying to explane the 0-541 up side down stuff,,,lol. I got it this addiction in 1978...so,,,,

So tell us a little bit about the headers. Who made them and what is different about them?

The headers are long tube with a 2.5 '' dump, and special tuned ends that Normam clay made, Dave ordered them special,,,I had them black coated, but it not doing so well.....kinda looking crappy


Image
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Davie GSO480
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Re: The Game Changer

Post by Davie GSO480 » Wed Jun 26, 2019 5:28 pm

Hambone79 wrote:Please help me understand my ignorant thinking what's so game changing about a V8 car motor DD spinning a prop built for a 4cyl AC Motor? Not bashing just trying to understand . beautiful boat BTW.

I dont guess the propeller know what it was de signed for, it just works.
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PJC
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Re: The Game Changer

Post by PJC » Wed Jun 26, 2019 5:46 pm

Some of the credit for the way that boat runs belongs to John fenner he set the bottom and replaced all of the soft rivets it had in the bottom, it went 90 with a bone stock 235 horse 540 on it

Davie GSO480
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Re: The Game Changer

Post by Davie GSO480 » Wed Jun 26, 2019 6:45 pm

PJC wrote:Some of the credit for the way that boat runs belongs to John fenner he set the bottom and replaced all of the soft rivets it had in the bottom, it went 90 with a bone stock 235 horse 540 on it
Yep John was at our club the second time I took this rig out,,,He was with Cory and his then new FedUp boat...
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CarMotorBarge
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Re: The Game Changer

Post by CarMotorBarge » Wed Jun 26, 2019 8:41 pm

Davie GSO480 wrote:The cam is one part of getting the direct drive to respond and run like it does.
Why would Water thunder give away his cam spec's?

My engine idle at 650 rpm's.
The cam lope goes away at 900 rpm...
Propellers tip speed is your limit here, the longer the prop, the faster the tip speed at the same engine rpm.
I have 2 different hubs from Sensenich, same Alpha blades. One is 66'', the other 68''
The 66'' at 3600 is at Mach .92, or 707 mph at tip, At 68'' at would be Mach .95 or 728 mph.
I turn the 68'' 3200 rpm's
Above (depending on tempture) much .92 your just making noise

With the 66''its a little quicker
with 68'' it has alot more low push, partly because its in cleaner air beyond the engine
I have a video racing a Hawk step with a 9 to 1, straight value 0-540,,,,let me see if i can figure out how to load it here.
You bought the engine. So you should be able to get the cam specs. This is how every other engine builder works. :stirpot:

So what intake does it have? Can't tell from the pictures.

Definitely a cool boat. 8)
14x7.5 Al David hull with 14 inch transom
419 CI Horsepower Barn LS3 with 2.88 Ox Box swinging 4 blade 83.5" R
GTO Rigging and B&S Tilt Trailer

Davie GSO480
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Re: The Game Changer

Post by Davie GSO480 » Wed Jun 26, 2019 8:47 pm

CarMotorBarge wrote:
Davie GSO480 wrote:The cam is one part of getting the direct drive to respond and run like it does.
Why would Water thunder give away his cam spec's?

My engine idle at 650 rpm's.
The cam lope goes away at 900 rpm...
Propellers tip speed is your limit here, the longer the prop, the faster the tip speed at the same engine rpm.
I have 2 different hubs from Sensenich, same Alpha blades. One is 66'', the other 68''
The 66'' at 3600 is at Mach .92, or 707 mph at tip, At 68'' at would be Mach .95 or 728 mph.
I turn the 68'' 3200 rpm's
Above (depending on tempture) much .92 your just making noise

With the 66''its a little quicker
with 68'' it has alot more low push, partly because its in cleaner air beyond the engine
I have a video racing a Hawk step with a 9 to 1, straight value 0-540,,,,let me see if i can figure out how to load it here.
You bought the engine. So you should be able to get the cam specs. This is how every other engine builder works.

I did not ask, nor do I want to know the cam spec's. :stirpot: :violent1:


So what intake does it have?
Holley Sniper EFI.
Can't tell from the pictures.

Definitely a cool boat. 8)
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Seven3
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Re: The Game Changer

Post by Seven3 » Thu Jun 27, 2019 1:17 am

So Davie GSO480, I’ve seen the pics of boats you have owned in the past. You and I have very similar tastes in boats (riveted aircraft hulls with 540 power). For your ‘next’ boat, would you stay this DD route, go LS w/gearbox, or go back to aircraft?

Davie GSO480
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Re: The Game Changer

Post by Davie GSO480 » Thu Jun 27, 2019 7:22 am

Seven3 wrote:So Davie GSO480, I’ve seen the pics of boats you have owned in the past. You and I have very similar tastes in boats (riveted aircraft hulls with 540 power). For your ‘next’ boat, would you stay this DD route, go LS w/gearbox, or go back to aircraft?
Good question man...depends what you want out of the boat..

I have a 13' Bennie Web with a RHS based LS gear box now,,,,,,,,,,,Its green.....its a family cruiser, double front seat, bimini top,,,and in about 5 sec is at 85 mph, so......for brute power, the LS gear box is the way to go.

Dont get me wrong,,,,,,,,,,,,,I think the Lycoming angle valve is one potent sexy motor..Ive has several,,,
I work on then myself, or go to Mike Thurman for internal work,,parts and his vast experance and knowledge....

I am trying to slow it down alittle,,,the direct drive is challenging,,,,,,,lets face it, if you put enough power on a wheelborrow it will run.

So with the DD, and a good lite strong 12'' boat,,,,you gotta twek it to run with the 0 540's.....its fun.....all the while burning Regular 93 gas. That I dont miss, getting and paying for LL100
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Davie GSO480
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Re: The Game Changer

Post by Davie GSO480 » Thu Jun 27, 2019 7:30 am

I'm in West Davie, Cell phone number is in my profile....anybody wanna talk, or come over and check this DD out...common....

This combo does have its place in airboating I will say....JMO
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Waterthunder
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Re: The Game Changer

Post by Waterthunder » Thu Jun 27, 2019 11:36 am

We have 5 of these DD's out there now they all run great! They are 3 different types of combo's, I will say one of them swings the same 70'' 5 blade saber as most AC guy's. It does turn more pitch more RPM's than what the prop manufacture told me the hot rodded A/C guy's turn. We are testing a budget DD combo that will cost the same or less than a well build angle valve 540, That is what Davie GSO480 has. That is a sweat running combo and another DD combo that is a nasty ass combo that swings the hell out of a 70'' 5 blade saber! To be honest I'm just having fun trying some cool ideas, don't have much interest in selling DD's there is no money in it, and most of all I'm not going to spend the time to prove it or convince people of it. Most everybody wants a big loud nasty ass sounding motor turning 6,000RPM's. So we would go broke building DD motors.
THE PROOF IS IN THE PROP!

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

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Seven3
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Re: The Game Changer

Post by Seven3 » Thu Jun 27, 2019 1:53 pm

Davie GSO480 wrote:
Seven3 wrote:So Davie GSO480, I’ve seen the pics of boats you have owned in the past. You and I have very similar tastes in boats (riveted aircraft hulls with 540 power). For your ‘next’ boat, would you stay this DD route, go LS w/gearbox, or go back to aircraft?
Good question man...depends what you want out of the boat..

I have a 13' Bennie Web with a RHS based LS gear box now,,,,,,,,,,,Its green.....its a family cruiser, double front seat, bimini top,,,and in about 5 sec is at 85 mph, so......for brute power, the LS gear box is the way to go.

Dont get me wrong,,,,,,,,,,,,,I think the Lycoming angle valve is one potent sexy motor..Ive has several,,,
I work on then myself, or go to Mike Thurman for internal work,,parts and his vast experance and knowledge....

I am trying to slow it down alittle,,,the direct drive is challenging,,,,,,,lets face it, if you put enough power on a wheelborrow it will run.

So with the DD, and a good lite strong 12'' boat,,,,you gotta twek it to run with the 0 540's.....its fun.....all the while burning Regular 93 gas. That I dont miss, getting and paying for LL100
Davie, I respect that honest opinion. And like I said I’ve seen your old boats, so I trust your judgement. I’ll be at the races on the 6th on a black 14’ Thurman with a 540, if I see you I’ll pull up and introduce myself.

SWAMPHUNTER45
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Re: The Game Changer

Post by SWAMPHUNTER45 » Sat Jun 29, 2019 6:54 am

Thank you for your post Dave look forward to hearing more on your LS R&D.

BATTLE READY
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Re: The Game Changer

Post by BATTLE READY » Sun Jul 14, 2019 1:21 pm

Davie,

Why did you go with an 11 ft boat compared to a 12 or 13 ft ? I know the other LS DD boat around here owned by Seth is also 11ft. Im guessing it is just a weight savings with the 11 ft ? I am not sure of the difference in weight in an 11, 12 and 13 ft boat but It was my understanding that Bennys 12 ft boats would out perform the 11 ft boats with the same power, and also the 13 out performs the 12 ft. I know you have had all makes of boats from Thurman, Don Davis, step hulls etc and just wondering why the 11 ft hull.

A buddy of mine was able to drive the other LS DD boat and he was very impressed. He is not getting rid of his LS Gearbox boat but he may build a LS DD.

Rob

Davie GSO480
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Re: The Game Changer

Post by Davie GSO480 » Tue Jul 16, 2019 8:56 am

Hi all....
I bought this boat and rigging used from Big John...its 11'9''....War Daddy....I am happy with the boat, rides good. Handles the weight good,,,,,this motor is just alittle lighter than a 0-540..raidator and all.
Remember,,,,,with regards to the boat....its weight down VS cubic inches of displacement....and hydro dynamics up
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terrible ted
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Re: The Game Changer

Post by terrible ted » Tue Jul 16, 2019 1:25 pm

The fuel economy and longevity. If he has the bearing worked out then it should have better life. My VO540 sucks fuel. I read allot of articles about prop performance. They were always below the speed of sound, So tip speed is critical.

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Re: The Game Changer

Post by Seven3 » Tue Jul 16, 2019 1:47 pm

Although I haven’t ridden on one yet, I’ve seen them run. I think they are a comparable alternative to the 540. I don’t think they’re going to outperform a strong 540 (at this point), and I don’t foresee them taking a big chunk of the market away from the 540, but for the guy who hates going to the airport for fuel, they are a viable option.

terrible ted
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Re: The Game Changer

Post by terrible ted » Wed Jul 17, 2019 1:13 pm

When I ran dd Chevy's the fuel economy was way better than my aircraft. Just none of them could hold up to the play created in the cranks by the prop. IF the longevity is there and the fuel mileage then I see them doing good.

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Re: The Game Changer

Post by Pulfordanny » Wed Jan 01, 2020 5:12 pm

How can I get ahold of Mike Thurman ? I’m looking for a set of 1200 mags for my continental 720 . Thanks in advance

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kwanjangnihm
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Re: The Game Changer

Post by kwanjangnihm » Wed Jan 01, 2020 8:26 pm

from an older thread:
Mike Thurman wrote:
Sun Jul 29, 2012 7:24 pm
If you need mags overhauled or for outright purchase or trade yours in for credit towards new ones. I have a large selection of mags and parts. Contact me if I can be of help. Mike Thurman 954-600-5181
" I don't care who you are back in the world, you give away our position one more time, I'll bleed ya, real quiet. Leave ya here. Got that? "

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Re: The Game Changer

Post by stbpope » Sat Feb 01, 2020 9:26 pm

nice boat

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