Forum Noobie, Electronics Oldie....Wet Exh.
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Forum Noobie, Electronics Oldie....Wet Exh.
Ok guys, my first post here. Been reading for a couple of years now, for ideas and inspiration. My question is about wet exhaust systems. Do I need to install some sort of check valve or one-way valve in my exhaust to prevent the water from backing into the engines when I kill her or she dies?
I am building my racing boat from scratch and just need some info. Thanks. I will post some pics and plans as soon as I can get a chance.
I am building my racing boat from scratch and just need some info. Thanks. I will post some pics and plans as soon as I can get a chance.
#2
RE: Forum Noobie, Electronics Oldie....Wet Exh.
ORIGINAL: mcgyverk
Ok guys, my first post here. Been reading for a couple of years now, for ideas and inspiration. My question is about wet exhaust systems. Do I need to install some sort of check valve or one-way valve in my exhaust to prevent the water from backing into the engines when I kill her or she dies?
I am building my racing boat from scratch and just need some info. Thanks. I will post some pics and plans as soon as I can get a chance.
Ok guys, my first post here. Been reading for a couple of years now, for ideas and inspiration. My question is about wet exhaust systems. Do I need to install some sort of check valve or one-way valve in my exhaust to prevent the water from backing into the engines when I kill her or she dies?
I am building my racing boat from scratch and just need some info. Thanks. I will post some pics and plans as soon as I can get a chance.
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
blizardo5, Thats a bit blunt mate (NO) What kind of answer is that????
mcgyverk, welcom to RCU Gas boats, sorry I can't answer your question but I hope someone will answer it better than the first guy.
Steve
mcgyverk, welcom to RCU Gas boats, sorry I can't answer your question but I hope someone will answer it better than the first guy.
Steve
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
Don't own a wet pipe myself but I understand the pickup is on the hull so no movement no water going in. If you have movement your engine is running producing exhaust and taking the water out with it to cool itself. I believe it also effects the engine tuning.
No check valve needed.
No check valve needed.
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
Hey guys, WOW fast answers! Ok on the check valve. STEVE: I have not completely made up my mind yet, but this may be a squirt drive setup (jet drive). I guess I need to give you guys more info. This is a Sabre Canard hybrid ( [link=http://www.rcuniverse.com/product_guide/boatprofile.cfm?boat_id=204]This Boat[/link] ) that has a total hull length of 72" ( Yes thats 6 feet. LOL). She has twin inline 33cc gas engines. And since I work in a machine shop with nice equipment I have been toying around with Supercharging them just for kicks.
#6
RE: Forum Noobie, Electronics Oldie....Wet Exh.
ORIGINAL: STEVE MARSHALL
blizardo5, Thats a bit blunt mate (NO) What kind of answer is that????
mcgyverk, welcom to RCU Gas boats, sorry I can't answer your question but I hope someone will answer it better than the first guy.
Steve
blizardo5, Thats a bit blunt mate (NO) What kind of answer is that????
mcgyverk, welcom to RCU Gas boats, sorry I can't answer your question but I hope someone will answer it better than the first guy.
Steve
#7
RE: Forum Noobie, Electronics Oldie....Wet Exh.
ORIGINAL: mcgyverk
Hey guys, WOW fast answers! Ok on the check valve. STEVE: I have not completely made up my mind yet, but this may be a squirt drive setup (jet drive). I guess I need to give you guys more info. This is a Sabre Canard hybrid ( [link=http://www.rcuniverse.com/product_guide/boatprofile.cfm?boat_id=204]This Boat[/link] ) that has a total hull length of 72'' ( Yes thats 6 feet. LOL). She has twin inline 33cc gas engines. And since I work in a machine shop with nice equipment I have been toying around with Supercharging them just for kicks.
Hey guys, WOW fast answers! Ok on the check valve. STEVE: I have not completely made up my mind yet, but this may be a squirt drive setup (jet drive). I guess I need to give you guys more info. This is a Sabre Canard hybrid ( [link=http://www.rcuniverse.com/product_guide/boatprofile.cfm?boat_id=204]This Boat[/link] ) that has a total hull length of 72'' ( Yes thats 6 feet. LOL). She has twin inline 33cc gas engines. And since I work in a machine shop with nice equipment I have been toying around with Supercharging them just for kicks.
#8
RE: Forum Noobie, Electronics Oldie....Wet Exh.
Also if you are building a racing boat, You might want to consider a dry tuned exhaust. Wet pipes do rob some power and slow you down. Most boats that run a wet pipe are sport boats or better known as play boats. The pipes are designed to be wet due to the fact that most are running a clutch so the pipe doesn't overheat when running. They also run much cooler for enclosed applications. If you are building a race boat you will find a dry tuned pipe much faster and increased rpms. A can muffler is the slowest and wet pipe next and a dry pipe last for the most power. Depending on engine and pipe you can adjust the dry pipe for length "hence" tuned pipe. A wet pipe uses only a coupler and a pipe, So limited tuning because of the water in the pipe breaks up the sound waves and causes differnt back pressure depending on RPM's so tuning a wet pipe would be very difficult problem. But if you do use a wet pipe you won't need and check valve as people say. "no" You can run a dry pipe enclosed you just need to consider the heat and adjust the venting to compensate for the extra heat. I have two warehouse hobbies team pro boats and they are both fun and have wet pipes, but they would never be competitive at 45+ mph. same boat with a dry powermaster tuned pipe i got 55+ and found the limit of the hull.
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
I have 2 boats with wet exhaust and if you pick up the boat from the water,remember bow up in case there is water in the pipe it will run out. If you are in an akward position like in a row boat and pick up the boat stern first you WILL have water run back in the engine. I know I have done it.
Glad to have you on board.
Pyro 1
Glad to have you on board.
Pyro 1
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
Also bearing in mind that a valve in a tuned pipe will stop the gases getting back into the engine.
Being a jet drive guy I don't think that that hull would be any issue for a jet drive. It is essentially a tunnel hull with a bit of a hydro aspect to it. Many of the river race jet boats look similar to that. I am currently building a tunnel hull river race jet boat myself.
http://www.rcuniverse.com/forum/m_65...age_146/tm.htm
Mine is the boat at the top. It is a bit different to your but I wouldn't think that it would have any problems.
What sort of jet are you looking to put in it. It will need to be big.
Being a jet drive guy I don't think that that hull would be any issue for a jet drive. It is essentially a tunnel hull with a bit of a hydro aspect to it. Many of the river race jet boats look similar to that. I am currently building a tunnel hull river race jet boat myself.
http://www.rcuniverse.com/forum/m_65...age_146/tm.htm
Mine is the boat at the top. It is a bit different to your but I wouldn't think that it would have any problems.
What sort of jet are you looking to put in it. It will need to be big.
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
That hull is a reverse rigger basically so where would you put the jet intake?
If your "supercharging" a 2 stroke you don't need any tuned pipe as well, since the case will be pressurized from the supercharger it would not let the returned charge come back from the pipe.
I think you will have a hard time finding anyone to race with.
If your "supercharging" a 2 stroke you don't need any tuned pipe as well, since the case will be pressurized from the supercharger it would not let the returned charge come back from the pipe.
I think you will have a hard time finding anyone to race with.
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
Ok, I think I have decided to go with a prop drive. I have to do some calculations on total weight, hull draft, on-plane height, and other stuff so I can order the correct prop. I would love to install a scale outdrive like the MHZ drives. Especially if anybody has one laying around for CHEAP ( or free). HA!!!!! LOL Yeah, right.
#14
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
You might want to express aloud a few more of the options you have in mind for this build as it is sounding like you may have plans to learn a few lessons the hard way.
Canards can be very quick when built and trimmed right. Trimmed wrong they can disappoint.
What motors are you using @33cc's a piece? She is sounding like a heavy Canard.
Save your time and $$ and go with a plain old strut and rudder. The stern drives wont take that kind of power for very long. An inline stock zenoah will have you grinding teeth in short order. Not convinced you will find too many going cheap (or free) but admire your confidence there
Trying to mechanically supercharge the motor is something that several have tried and thus far I dont believe any have achieved actual gains. The successful option that is a standard in the hobby is tuned pipes which make some very notable power gains. Blowers will always take power to make power - you will need a very efficient blower to give yourself any chance to make up for the losses. Dont get me wrong - I hope you succeed with the idea - The world will be your oyster if you do.
Canards can be very quick when built and trimmed right. Trimmed wrong they can disappoint.
What motors are you using @33cc's a piece? She is sounding like a heavy Canard.
Save your time and $$ and go with a plain old strut and rudder. The stern drives wont take that kind of power for very long. An inline stock zenoah will have you grinding teeth in short order. Not convinced you will find too many going cheap (or free) but admire your confidence there
Trying to mechanically supercharge the motor is something that several have tried and thus far I dont believe any have achieved actual gains. The successful option that is a standard in the hobby is tuned pipes which make some very notable power gains. Blowers will always take power to make power - you will need a very efficient blower to give yourself any chance to make up for the losses. Dont get me wrong - I hope you succeed with the idea - The world will be your oyster if you do.
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
ORIGINAL: TwinJetMax
In the normal spot. The central hull.
In the normal spot. The central hull.
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RE: Forum Noobie, Electronics Oldie....Wet Exh.
Just updating. Almost done with the cylinder water jackets. Been reading up on 2stroke turbo/superchargers.