RedRocket1647545505 Posted June 28, 2007 Report Share Posted June 28, 2007 3 seconds of Google yeilds: "A power valve is just a piece of metal that moves down and covers part of exhaust port making it smaller. Big ports mean big horsepower, but they also mean narrow power band. By making the port smaller, the power valve helps make the power band wider. It does this by keeping more of the fuel mixture in the cylinder, and out of the exhaust pipe, at lower RPM." "The power valve should be closed at Low RPM and Open at High RPM. The Power Valve does this with centrifugal weights (Governor) that over come spring pressure and move the Power Valve Linkage. The linkages usually are spring loaded. This is to close them at low RPM." By this article, logic would tell me that tightening the spring pressure would give you more bottom end power, but less top; and vice-versa. Quote Link to comment Share on other sites More sharing options...
RedRocket1647545505 Posted June 28, 2007 Report Share Posted June 28, 2007 http://i14.tinypic.com/4v516om.jpg Are the ones in the blue squares on the exhaust ports? I'm inclined to say that, if they are, these are probably powervalves. I'm also going to guess that the two on the exhaust expansion chambers are the RAVE valves that Lustalbart mentioned, which appear to look very similar, as he mentioned. Quote Link to comment Share on other sites More sharing options...
HAOLE Posted June 28, 2007 Report Share Posted June 28, 2007 http://i14.tinypic.com/4v516om.jpg Are the ones in the blue squares on the exhaust ports? I'm inclined to say that, if they are, these are probably powervalves. I'm also going to guess that the two on the exhaust expansion chambers are the RAVE valves that Lustalbart mentioned, which appear to look very similar, as he mentioned. those are on the intake side... Never mind I might be wrong... I have not looked at one of those in a year. Quote Link to comment Share on other sites More sharing options...
RedRocket1647545505 Posted June 28, 2007 Report Share Posted June 28, 2007 those are on the intake side... Never mind I might be wrong... I have not looked at one of those in a year. I might be wrong as well. Those silver canisters appear to be on some sort of intake. I wouldn't think rubber hoses and worm clamps would be used on an exhaust. I dunno. I'm learning as well. I've always heard of powervalves from back in my dirtbike days, I just never took the time to learn WTF they actually were. Quote Link to comment Share on other sites More sharing options...
HAOLE Posted June 28, 2007 Report Share Posted June 28, 2007 I am almost sure that the ones in blue are on the exhaust side. The allen bolts that hold the exhaust one are a pain to get out, unless you have the allens with the ball end. I remember now, that should be the exhaust side. Quote Link to comment Share on other sites More sharing options...
Guest 614Streets Posted June 28, 2007 Report Share Posted June 28, 2007 They regulate water into the water box , the ones in the blue boxes are rave valves. Leave it stock , or add a aftermarket water injection pipe. Quote Link to comment Share on other sites More sharing options...
SPLN SUX Posted June 28, 2007 Report Share Posted June 28, 2007 If your looking for more top end, change the impeller to a slightly smaller diameter, with a deeper pitch. Also, you can change out the thrust cone (nossel on the back). A longer, narrower nossel will yeild a few mph, but you lose the bottom end, but not much. A shorter wider nossel has the opposite effect. Spraying doesnt really do much. Itll get you out of the whole quick, but because all your doing is raising your max rpm... and depending on the impeller, it could cavitate and blow your shit up. Youre better off with boost Quote Link to comment Share on other sites More sharing options...
RedRocket1647545505 Posted June 28, 2007 Report Share Posted June 28, 2007 Youre better off with boost On a 2-stroke? Let me know how that works out. Quote Link to comment Share on other sites More sharing options...
SPLN SUX Posted June 28, 2007 Report Share Posted June 28, 2007 On a 2-stroke? Let me know how that works out. never done that i take it? It requires quite a bit more math and can make RETARDED amount of power... my little .12ci novaRossi motor made 4.2hp... let me say taht again... 2.5cc's, 4.2HP! I used a brushless 440electric motor on a ducketed fan set up... was very awkward, but required the use of a 6v fuel pump for the 4 stroke air planes... so FI x 2 on a 2 stroker. Its possible, but rough to make work. I bet it would be pretty easy to boost one of those... i shouldve done that to the old "HaterRaider" but we sprayed it instead. Quote Link to comment Share on other sites More sharing options...
Guest 614Streets Posted June 28, 2007 Report Share Posted June 28, 2007 I bet it would be pretty easy to boost one of those... Actually it wouldnt be easy. It would be stupid. Quote Link to comment Share on other sites More sharing options...
SPLN SUX Posted June 28, 2007 Report Share Posted June 28, 2007 Actually it wouldnt be easy. It would be stupid. Youre intitled to your opinion, but just so you know... youre wrong Besides, you being a Marine mech grad, you shouldnt have any problem figuring it out. Boosted double pumpers: four duh when. Quote Link to comment Share on other sites More sharing options...
Guest 614Streets Posted June 28, 2007 Report Share Posted June 28, 2007 Ok............... Quote Link to comment Share on other sites More sharing options...
SPLN SUX Posted June 28, 2007 Report Share Posted June 28, 2007 Ok............... you must be one of those people who dont like to do one off work... MMI probably just teaches you how to fix things and not modify them... questions i dont know the answer to, but i do know boosting a two stroke is not "stupid", its just tough to make work without the right porting on the case. For example, i couldnt get it to work with the single port, but worked fairly well with the triple port, and made all the power the head screws could handel on the 5 port. Like i siad, a shit ton more math and physics... and you pretty much have to forget everything you know about boosting 4 storkers. Quote Link to comment Share on other sites More sharing options...
Guest 614Streets Posted June 28, 2007 Report Share Posted June 28, 2007 How are you going to "boost that engine" ? Its not even logical to me. And what do you mean by me being able to figure it out. Its a ridiculous Idea. Quote Link to comment Share on other sites More sharing options...
Guest 614Streets Posted June 28, 2007 Report Share Posted June 28, 2007 you must be one of those people who dont like to do one off work... MMI probably just teaches you how to fix things and not modify them... questions i dont know the answer to, but i do know boosting a two stroke is not "stupid", its just tough to make work without the right porting on the case. For example, i couldnt get it to work with the single port, but worked fairly well with the triple port, and made all the power the head screws could handel on the 5 port. Like i siad, a shit ton more math and physics... and you pretty much have to forget everything you know about boosting 4 storkers. Oh wait I have my reasons, first off lets not assume. Second That engine is not engineered with port timing for boost. It doesnt have the fuel system for boost. Pistons are wrong for boost. Ignition is too weak. Nothing on that entire system was engineered for boost. You mean to tell me you could design a complete legitimate boost system for that engine? Reliably? It would never work. Never. What are you going to do with all that extra heat? This is pointless discussion. Only mods for this are current aftermarket parts, nothing else is safe or reliable, and thats what you want in a boat. Quote Link to comment Share on other sites More sharing options...
SPLN SUX Posted June 28, 2007 Report Share Posted June 28, 2007 Oh wait I have my reasons, first off lets not assume. Second That engine is not engineered with port timing for boost. It doesnt have the fuel system for boost. Pistons are wrong for boost. Ignition is too weak. Nothing on that entire system was engineered for boost. You mean to tell me you could design a complete legitimate boost system for that engine? Reliably? It would never work. Never. What are you going to do with all that extra heat? This is pointless discussion. Only mods for this are current aftermarket parts, nothing else is safe or reliable, and thats what you want in a boat. Keep in mind, ive been talking about a glow engine that runs on methanol... heat isnt a problem, timing isnt a problem, and it detonation.. well thats how it runs... youre talking purely premix spark plug engine. Im well aware of the hurdels on a sparky... you just have to over come them. Putting helicopter engines in a boat that rides on only 5% of its hull isnt very safe either, but people do it. Anything can be reliable if you do it right. Quote Link to comment Share on other sites More sharing options...
Guest 614Streets Posted June 28, 2007 Report Share Posted June 28, 2007 Keep in mind, ive been talking about a glow engine that runs on methanol... heat isnt a problem, timing isnt a problem, and it detonation.. well thats how it runs... youre talking purely premix spark plug engine. Im well aware of the hurdels on a sparky... you just have to over come them. Putting helicopter engines in a boat that rides on only 5% of its hull isnt very safe either, but people do it. Anything can be reliable if you do it right. Dude I know where your coming from, your a tuner , a hot rodder and hot rodders do shit like that. But this is a 2 stroke boat motor with RAVE exhaust technology. It would take massive reasearch , the kind that would rival the best engineerers at any of the Marine corporations to build what it would take to do the things your talking about. Unless you coble up a system and get it to run for a day with less power than it already has ,catch it on fire , kill little jenny and make fido swim for help , surviving to tell the world I boosted it! That reliability would cost a whole shit load of cash and time. Its not even worth thinking about. Besides when a car breaks down you have options , when a boat breaks down you have a whole lot less. Its just unpractical , youd be better off buying a whole new boat to tackle the reasons why you need that much more power in this situation. Quote Link to comment Share on other sites More sharing options...
SPLN SUX Posted June 28, 2007 Report Share Posted June 28, 2007 Dude I know where your coming from, your a tuner , a hot rodder and hot rodders do shit like that. But this is a 2 stroke boat motor with RAVE exhaust technology. It would take massive reasearch , the kind that would rival the best engineerers at any of the Marine corporations to build what it would take to do the things your talking about. Unless you coble up a system and get it to run for a day with less power than it already has ,catch it on fire , kill little jenny and make fido swim for help , surviving to tell the world I boosted it! That reliability would cost a whole shit load of cash and time. Its not even worth thinking about. Besides when a car breaks down you have options , when a boat breaks down you have a whole lot less. Its just unpractical , youd be better off buying a whole new boat to tackle the reasons why you need that much more power in this situation. You know whats unpractical? Women. Unlimited cost and maintence with limited fun kick back... and even that costs money if you use a condem. Quote Link to comment Share on other sites More sharing options...
Guest 614Streets Posted June 28, 2007 Report Share Posted June 28, 2007 You know whats unpractical? Women. Unlimited cost and maintence with limited fun kick back... and even that costs money if you use a condem. http://www.mtvasia.com/News/200705/images/07014267.jpg Quote Link to comment Share on other sites More sharing options...
Guest 614Streets Posted June 28, 2007 Report Share Posted June 28, 2007 [Chorus: R.Kelly] I'm A, I'm A, I'm A, I'm A Flirt Soon As I See Her Walk Up In The Club (I'm A Flirt) Winkin Her Eyes At Me, When I Roll Up On Them Dubs (I'm A Flirt) Sometimes When I'm With My Chick On The Low (I'm A Flirt) And When She's Wit Her Man Lookin At Me, Damn Right (I'm A Flirt) So Homie Don't Bring Your Girl To Meet Me 'cause (I'm A Flirt) And Baby Don't Bring Your Girlfriend To Eat 'cause (I'm A Flirt) Please Believe It, Unless Your Game Is Tight And U Trust Her Then Don't Bring Her Around Me 'cause (I'm A Flirt) [Verse 1: Kells] Now Swear To Tell The Truth And The Whole Truth When It Comes To Hoes I Be Pimpin Like I Supposed To Rollin LIke I Supposed To Shinin Like I Supposed To In The Club, Fuckin Wit Honeys Like I Supposed To I Don't Understand It When A Nigga Bring His Girlfriend To Club Freakin All On The Floor Wit His Girlfriend In The Club And Wonder Why All These Playas Tryin To Holla At Her Just Soon As She Go To The Bathroom, Nigga I'm Goin Holla At Her A Dog On The Prowl When I'm Walkin Through The Mall If I Could Man I Probably Would Fuck Wit All Yall Yeah, Yeah Homie U Say She Yo Girlfriend But When I Step Up To Her I'm Be Like Cousin Believe Me Man, This Is How Them Playas Do It In The Chi And Plus We Got Them Playette Flirters In The Chi Now The Moral Of The Story Is Cuff Yo Bitch 'cause Hey I'm Black, Handsome, I Sing Plus I'm Rich And (I'm A Flirt) [TIP Speaking:] Hey Homie, If U Ain't Gettin No Money U Better Keep Her Away From Me Ya Dig. [Verse 2: TIP] Well If U Love Ya Girl And Wanna Keep Ya GIrl Don't Be Walkin Up And Askin Me To Meet Ya Girl 'cause I'm Well Enough A Flirt When I Speak To Girl She Winked Her Eyes On The Slide I Seent U Girl Better Treat Your Girl Right 'cause Another Man Will Better Eat Ya Girl LIke Another Man Will 'cause U Leave Your Wife And I See Ya Wife That Be For Real How Long U Think That's Finna Be Ya Wife Well I'm Livin The Life You Just Gettin It Right Your Old Lady Look At Me 'cause U Ain't Hittin It Right She Probably Used To Like U 'cause U The ??? Type That's Until I Came Along And Put Some Dick In Her Life Wanna See ???? I Noticed She Was Checkin Me And Diggin The Ice And If I Get That Tonight Better Hit That Twice I Can Even Make Her Mine If I HIt That Price You Know Smack That Thang Sit That Right Upon That Dress Yeah That's Right Pullin On Her Hair Like We Gettin In A Fight Yeah I Know It's Kinda Tight But It'll ???? Just Right So If Yo Girl Sexy And She Test Me Don't Be Upset G 'cause U Might Catch Me Tryin To Catch A Glance Up Her Skirt We Playing In My Vert ??? Then If I See Her And I Like Her Then I'm A Flirt [Verse 3: T-Pain] When I Pull Up To Club All The Shawties Be Like (Damn 28's) Then I Be LIke Girl U Know Just Who I Am (Don't Hate) Say I Done Fell In Love Wit A Stripper Yall All I Do Is Flirt With Her, And I Get Them Draws And I Don't Need No Help, I Got It Down Pact Teddy Paine Was Born To Flirt Now U Can't Down That Now I'm Flirt With Her Whether I'm In Or Out Of Town That's Why They Call Me Teddy Bend Her Ass Down I be like Como te llama lil momma Me llama Pain What Is Yo Name I'm Feelin Yo Vibe And I'm Hopin U Feel The Same I'm A Wink My Eye And Let U Know I Got The Game When I Pass By I Know Exactly What U Say He's So Fly And He's So Cool Hey Shawty(Hey Shawty) What It Do He Mad 'cause I'm Lookin But I Already Touched Her I Got Yo Boyfriend Mad 'cause (I'm A Flirt) [Chorus] [Verse 4: Kells] It's The Remix Now If U Walk Up In The Club Wit A Bad Chick And She Lookin At Me Then I'm Gon Hit Man Jackin For Chicks I Tried To Quit But I'm Playa Homie So I Had To Hit While U Buyin Her Drinks (In The Club) Actin Like U (In Love) Stunnin Like U (All Thug) We Was (Switch Numbers) She Lookin At U When I Walk By U Turn Yo Head, She Wink Her Eye I Can't Help If She Checkin For A Platinum Type Of Guy She Be Callin Me Daddy, And I Be Callin Her Mommy She Be Callin U Kelly, When Yo Name Is Tommy I Don't Know What Yall Be Thinkin When U Bring Em Round Me Let Me Remind U That I Am The King Of R&B Do U Know What That Means That Means If U Love Yo Chick Don't Bring Her To The VIP 'cause I Might Leave Wit Yo Chick Just Keepin It Real It's A Playa's Field Don't Take No Chick To The Club When U Just Met Her 'cause I'm Flirt Wit Her (Right) He Gon Flirt Wit Her (Right) And If She Lickin Dat Good Shyt She Gon Flirt Wit Her [Chorus: Til Song Fades] Quote Link to comment Share on other sites More sharing options...
HAOLE Posted June 28, 2007 Report Share Posted June 28, 2007 In my opinion they only mods I would do is off the shelf for a couple of reasons. First of all, the mods may have to be Coast Guard approved for use on a boat. Secondly having to be towed to shore is not good. Boats are like airplanes, reliable is the better than speed. If you want a boat that you can modify like a car I would look into a old jet boat that has an open engine bay. Then you can get off the shelf turbo and blower set ups that are Coast Guard approved. Other than that, I am a person that says leave the boat stock. Quote Link to comment Share on other sites More sharing options...
Sam1647545489 Posted June 28, 2007 Author Report Share Posted June 28, 2007 Well everyone thanks for the help in this thread. I am not goin to mess with it, I am just goin to call Riva and see what they have for some aftermarket stuff. I know all about the impellors and grates and stuff like that for the jet to pick up a few mph, I just thought those cans where like cats where as I could just toss them out and run a straight pipe off of the mufflers. Quote Link to comment Share on other sites More sharing options...
Sam1647545489 Posted June 28, 2007 Author Report Share Posted June 28, 2007 Austin here is a pic of the whole motor. The motors have 2 of the rave valves on top. http://i161.photobucket.com/albums/t214/ls2sam/P6270003.jpg Quote Link to comment Share on other sites More sharing options...
Nitrousbird Posted June 28, 2007 Report Share Posted June 28, 2007 Well you have whats called a wet exhaust. You can run a dry one, but it creates quite a bit of heat, and can cause a fire if not ventalation and shielding is not paid attention to. A lot of the fast boats I.E. Baja's, Cig's, Donzi's, Fountian's etc. all have this... you can see them spitting the water out of the pipes... its a slightly different setup though. A wet exhaust is nothing special; a closed cooling system is actually considered rare. Pretty much all boats have a wet exhaust system, not just expensive ones. IMO it makes more sense; why not use the lake as your radiator? Sam, I don't agree with the Rick about modding a boat and being reliable like an airplane. If an airplance motor dies, you crash and die with it (at least a lot of the time). Boat motor dies...you sit in the water and wave someone down to tow you in. I've been towed in a number of times (before I got all the bugs worked out of my boat); it's not a big deal. Throw a few bucks to the guy that towed you in, and be on your way. If you want more power, just go to a Jet Ski forum and see what they are doing to those motors. Quote Link to comment Share on other sites More sharing options...
Total Sign Posted June 28, 2007 Report Share Posted June 28, 2007 First off- SPLN SUX, you cannot run a dry exhaust system in a boat. You will burn the thing up. You can go to a reduced water setup, where all of the water goes through the waterjackets on the pipe, but a reduced amount actually mixes with the exhaust. The semi dry pipes are nice when you are running a big cam, less chance of reversion. You can effectively run nitrous in a boat. Been there done that. You need to put a prop on with more pitch than the engine can turn w/o juice. The boat is a dog off the spray, and most of the time needs a couple quick taps of the button to get on plane. We even put nitrous on a sea doo a while back, it was running mid 80's on radar (new supercharged ones wont break 74 radar). Sam, that is the most inefficient drivetrain on the water. The cash you will spend to make any real difference would buy you a real boat. Dr Rick, the mods do not have to be CG approved. Braided steel line is not, how many boats have you seen that on? CG is a guideline. Most people do not know that a boat does not have to be CG approved to be on the water. Quote Link to comment Share on other sites More sharing options...
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