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Old 07-27-2009, 05:47 PM   #16
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Originally Posted by Davidka View Post
Boats and race planes run far higher rpms than we do, still with long (about 4x as long) pipes. They do run at nearly constant rpm though, they have little need for bottom end power or sharp throttle response.
Well, if you want to put a pipe 4 times longer on your car, be my guest. It will take some fabrication to coil all that pipe around to fit in the car but it can be done. The end result will be a very slow car. Might launch really well (maybe) but sure wont have any top end at all.

Believe me, as competitive as RC is, someone would have made one if there was any benefit. Believe it or not, our pipes are actually very well designed and in principal, identical to those plane and boat pipes you love so much. Merely adapted for our needs in terms of displacement, powerband, rpm and rules.
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Old 07-27-2009, 05:58 PM   #17
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Also, boat and plane motors don't run more RPM then we do. Here is a dyno run of a boat motor.

http://rcboat.com/dynoind.htm

Notice it makes peak power at about 23,000. Ours usually make peak power at at least 26,000 and some go even higher. Plus we need them to continue to make decent power all the way up to about 40,000. A boat motor will never see that much rpm unless something breaks.
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Last edited by wingracer; 07-27-2009 at 06:11 PM.
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Old 07-27-2009, 08:07 PM   #18
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While I don't see on that link where it says what the displacement that boat engine is, I'm going to bet that 4.4hp happening at 23,000rpm makes it much larger than a .21 (65% nitro?!?!?). I'd be interested in seeing a dyno chart for a .21 boat engine.

I am well aware that a long pipe won't fit in our cars, that's exactly the point. If you look at the pipes used in plane and boat racing, the pipes are very long, they are never short, no matter what the given RPM range is.
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Old 07-27-2009, 08:24 PM   #19
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Listen to this and tell me if you've ever heard a buggy engine wind like this:

http://www.youtube.com/watch?v=QjR-K...eature=related
http://www.youtube.com/watch?v=mMdZb...eature=related

Also notice the starting method in the second one. Not sure what's going on there...
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Old 07-28-2009, 06:46 PM   #20
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Quote:
Originally Posted by Davidka View Post
I am well aware that a long pipe won't fit in our cars, that's exactly the point. If you look at the pipes used in plane and boat racing, the pipes are very long, they are never short, no matter what the given RPM range is.
I never said that a longer pipe wouldn't fit, I said it would require a different design and that if there was any benefit, someone would do it. Bottom line, make the pipe longer and the motor would make more power at lower rpm but less at higher rpm and less peak power.

Look, if you refuse to believe me, there are several sites and books that explain two stroke pipe design. Look it up and run the numbers. You will find that our pipes are right in line with where they should be. I have done so.

Also remember that our pipes are longer than they look. Try to imagine uncoiling that manifold and look at how long it would be. Also remember that pipe length is really just the distance from the center of the piston to the end of the divergent cone (the weld joint on most of our pipes). Everything after that has little effect on the RPM range the pipe works at. You just have a convergent cone, whose length and angle effects the strength of the return pulse (which can affect the powerband but really doesn't effect the rpm that peak power comes at) and everything after that is basically just noise reduction.
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Old 07-29-2009, 05:33 PM   #21
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are you guys coating your stuff at home or are you sending it off to get it done. I am very interested in doing my own ceramic coating but i dont know where to buy th supplys i need
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Old 07-29-2009, 09:18 PM   #22
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are you guys coating your stuff at home or are you sending it off to get it done. I am very interested in doing my own ceramic coating but i dont know where to buy th supplys i need
I have a place in my town do it. The prep. is key to having it "stick". If you are going to do it, have it done right. The air dry product has a higher heat rating, but is more finicky than baked on, as far as prep. goes.

just my $.02

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Old 07-30-2009, 07:37 AM   #23
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Cerakote is a ceramic based paint that is used in the firearms community for making firearms look tacticool.

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Old 07-30-2009, 07:50 AM   #24
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First of all, I believe that the Ceramic pipes cant be run a saction events.

Second - whats the point - you will not get any more power out of it at all, its not going to make you driver better, its not going to keep all four wheels down, ect

Thrid- the numbers on the pipe need to be visible

A long pipe for what - what would be the benificial point
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Old 07-30-2009, 08:52 AM   #25
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Cerakote is a ceramic based paint that is used in the firearms community for making firearms look tacticool.

Buy Here
oven cure product has a low heat threshold. not real good for our exhaust.
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Old 07-30-2009, 09:28 AM   #26
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First of all, I believe that the Ceramic pipes cant be run a saction events.
There is no rule against any coating on pipes. Though yes, the numbers must be visible.

Hell, I saw a gold plated pipe a few months ago. Very pretty, haha.
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Old 07-30-2009, 09:51 AM   #27
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I got sick of the cruddy look of my pipes after the fuel and dirt baked on to it. I powdercoated is with a standard flat black and it looks great. I thought the heat may have been an issue but its held up awesome so far.
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Old 07-30-2009, 10:25 AM   #28
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Originally Posted by wingracer View Post
There is no rule against any coating on pipes. Though yes, the numbers must be visible.

Hell, I saw a gold plated pipe a few months ago. Very pretty, haha.
on page 1 of this thread I posted the gold pipe/header I did. At the same time, I did the aluminum head on my OS Speed. This is the air dry ceramic coating. motor temps stayed the same, if not lower, (not trying to make claims) and cleans up with glass cleaner.

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Old 07-30-2009, 03:11 PM   #29
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Yeah I saw that but I am talking about actual GOLD. This thing looked like jewelry. He wasn't actually using it of course.
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Old 07-30-2009, 03:19 PM   #30
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Quote:
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Yeah I saw that but I am talking about actual GOLD. This thing looked like jewelry. He wasn't actually using it of course.
That's would be killer. Very glam.
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