Tank in Whiplash 45

[dr gary turner]

Would a single Right sided tank in a whiplash 45 be bad? Does there need to be two to balance the boat?

 

[larcor69]

Could you fit a tank large enough to make it through 10 laps?

 

[dr gary turner]

Could you fit a tank large enough to make it through 10 laps?

I think so, I plan to make a mock up with wood to see if we can get 18 oz tank in. So if the volume is not the issue the answers to the Questions are?

 

[P THOMAS]

Plan on using 14 oz tank on the right, should be all you need, my thirsty mac45 run the race ok on 14oz. You probally will need some weight on the left anyway to adjust the ride and balance point.

There are a couple good running blazer40 in dist 14, they can answer best setup.

 

[dr gary turner]

Plan on using 14 oz tank on the right, should be all you need, my thirsty mac45 run the race ok on 14oz. You probally will need some weight on the left anyway to adjust the ride and balance point.

There are a couple good running blazer40 in dist 14, they can answer best setup.

Thanks Phil, Have a Merry Christmas. Doc

 

[FloridaScaleBoater]

Plan on using 14 oz tank on the right, should be all you need, my thirsty mac45 run the race ok on 14oz. You probally will need some weight on the left anyway to adjust the ride and balance point.

There are a couple good running blazer40 in dist 14, they can answer best setup.

Thanks Phil, Have a Merry Christmas. Doc

What, are you guys giving up on the Bullard Built sport-40's

 

[El Zorro]

I would put the tank on the left side of the boat. My Phil Thomas Sport 40 has a 12 ounce plastic tank on the left side ( under the deck ) with a 2 ounce hopper tank inside the right engine rail just to the rear of the engine. It will almost empty the 12 ounce tank during a heat race with a good needle. Even with the tank on the left side I still have 2 ounces of lead taped to the rear of the left sponson to keep it on the water. And I'm not running the horsepower that you guys are running ( old blue head Picco ). Even so, the boat did pretty good this year.

Dick Tyndall

 

[Dick Loeb]

In my 40 Whiplash I ran 2- 8 oz Walt Barney tanks under the deck beside the engine on the balance point. ( CMB 45 RS )

 

[David Murany]

We run 2 of the 8 oz hard plastic sullivan tanks under the deck on my dads and fuel is never an issue but I would definitely suggest a hopper if you are gonna run one big tank. As Phil stated though tanks on both sides helps with the balance of the boat. Keep them as far forward as you can.

Dave

 

[SayMikey]

I believe Mike Starrett has one tank and if he throws in too early I WIN lol he runs out of fuel. I have one on the build table and will run a pair of 8s

 

[Mike Starrett]

I ran a 8oz under the right deck, a 4oz round tank right next to it and a 2 oz hopper under the carb. Never really had problems running out of fuel. I always waited to start because I thought it would be just that much later before I blew it off. More likely it just quit running. I didn't have my pipe inside the boat so I could run the 4oz between the stuffing tube and the right side. I did have to play around with the hopper tank to find a setup that worked though. I've seen them run fine with 2- 8oz slant ovals under the decks and no hopper(as suggested in the instructions).

 

[dr gary turner]

Thanks, We place the hopper inside the tank. I was my opinion and it maybe wrong, that the tank needed to be on the RT in order to keep the RT sponson planted to enhance going through the turns. But it seems it is the left sponson that lifts, according to Dick and others ?????????????? BTW Dick I am looking forward to the twin fin. The one I have works vary well on my single f-hydro.

Also BTW where should the balance point be? Is there a "yaw" balance point ie RT to LT?

 

[El Zorro]

I always start out with the turn fin in a " neutral " position. This lets me know what is going on with the boat trim ( Center of Gravity, strut height, angle, etc, ). If the right sponson " rides up " or bounces in the corner then you can adjust the bottom of the fin slightly to the rear of the boat. This will suck the right sponson back down to the water. If you go too far with this adjustment it will cause excessive drag and make the boat pull to the right. Don't know anything about the Whiplash boat ( Dick Loeb has one ) but my boat balances about one inch behind the rear of the sponsons.

Glad the turn fin on your F boat is working well. Busy time around here catching up on fin orders!

Dick Tyndall

 

[dr gary turner]

Dick, A new twin is in the jig and looking forward to using your fin on the boat.

 

[dr gary turner]

Big week end, got the radio in and there is only one way to get it all in switch, receiver, mixture control servo throttle servo rudder servo and battery. Time spent at Mark's shop and help and combine expertise of the two of us helped get it to work.

Designed tank and a slight mod to the structure and about 15 oz all in one tank on the RT side. This was only possible by first mounting the motor on an angle and not flat to decrease the height of the shaft log which also markedly reduced the "S" bend in the shaft log. Once tank is built[Mark's handy work] and will post pictures which maybe helpfull for other whip builders.

 

[El Zorro]

The torque of the engine normally will keep the right sponson planted on the water. That is why I put my tank on the left side of the hull. The engine torque and the turn fin is what will make the boat go around the corners. Maybe the design of the Whiplash boat works better with the tank on the RIGHT side............I don't know. My PT Sport 40 has always been a bit "flighty " and before this year I added some curvature to the bottom to take out some lift. I didn't change the Center of Gravity when I did this and the boat now stayed on the water with no loss in speed or handling. I have heard of many Scale hydros, Sport Gas and Gas Thunderboat hydros having to add weight to the LEFT sponson just to get the boat to ride correctly. This has to be because of the torque of the engine. I don't pretend to know a lot about R/C hydroplanes because I always ran mono hull boats up until a few years ago. But I do go to the test pond with a couple of guys that know a little bit about hydros and how to set them up. I try to listen to what they say and both have been a big help in getting my hydros to do what they are supposed to do.

Let us know how things work out with your boat.

Dick Tyndall

 

[Mike Starrett]

I would recommend that if you don't have the Blazer turn fin for your boat that you at least try one. I found it to be far better than any other one I tried. Also if you have problems or questions about your Whiplash I found Bob and Brian both to be excellent sources of information. They know their boats inside out and were always willing to answer questions.

 

[FloridaScaleBoater]

The torque of the engine normally will keep the right sponson planted on the water. That is why I put my tank on the left side of the hull. The engine torque and the turn fin is what will make the boat go around the corners. Maybe the design of the Whiplash boat works better with the tank on the RIGHT side............I don't know. My PT Sport 40 has always been a bit "flighty " and before this year I added some curvature to the bottom to take out some lift. I didn't change the Center of Gravity when I did this and the boat now stayed on the water with no loss in speed or handling. I have heard of many Scale hydros, Sport Gas and Gas Thunderboat hydros having to add weight to the LEFT sponson just to get the boat to ride correctly. This has to be because of the torque of the engine. I don't pretend to know a lot about R/C hydroplanes because I always ran mono hull boats up until a few years ago. But I do go to the test pond with a couple of guys that know a little bit about hydros and how to set them up. I try to listen to what they say and both have been a big help in getting my hydros to do what they are supposed to do.

Let us know how things work out with your boat.

Dick Tyndall

Dick,

I understand where your coming from here,, but there is always, more than one way to skin a cat.

On my Coor's scale,, (Johnson design) ALL of my radio equipment is in a box out on the STBD side, JUST FWD of CG

On my new Sport-40 (Johnson design) the radio box is in the same place

In my Old, Trusty Thomas sport-40, I have a 16oz tank mounted under the STBD deck, just FWD of CG, W/ a 1oz hopper under carb.

Why have we done this?? Keeps the turn fin "Hooked up"

And probably ONE of the best sport-40 & scale heat race boat builders/driver's in the country (Jack StClair) came up with this idea quite a few years back,, and Jack has some fast, handling boats!!

 

[El Zorro]

Hi Rick,

I have always been a firm believer in " there is always more than one way to skin the cat ." Mr. St.Clair's Scales and Sport 40 hydros that I have seen have always been great running boats and he is a pretty good driver, too. However, I have never seen a turn fin that was curved or had a hook in it on any of his boats.............only a straight fin on about a 15 degree angle. You would almost have to weight the RIGHT side of the boat to help keep the boat hooked up in the corners. The whole purpose of having the hooked/curved fin is to keep the boat on the water in the corners, especially in rough/race water. If we play with these boats long enough we will find a LOTof ways to get them to do what we want them too, huh? Your stuff runs pretty good too, by the way...............

Have a great New Year, my friend!

Dick Tyndall

 

[dr gary turner]

Thanks for the info. We will see how it does. I do have a blazer tur fin. Once the tanks is built and tried in its assigned position we will put the deck on. Once I get the tank I will post some pictures. The tank actually extends to the shaft log so some of the tank is in the middle of the hull. also as the boat goes through the turns the fuel will be displaced to the center of the hull. A tank in the middle of the hull with baffiling to prevent shifting of the fuel from centrifical force would be the most ideal.