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Tuned pipe materials and band questions

Old 10-21-2008, 07:26 AM
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01VIPER27
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Default Tuned pipe materials and band questions

The need to learn is a must to me. I cant seem find a post on this topic. Please educate me.

Is there a particular reason why certain racers and engine builders use the 2" band metal pipe other than the reasoning that it works?

-metal pings / resonate better than aluminum that is obvious but it is also louder, not good in a neighbourhood pond.
Is there an in between pipe to be bought or do I just get the best and loudest and put a muffler to it?

-less bends on header or straight header is best this I understand why.
Why 0 band overr 1" or 2" band is better I'm very green on, what is the reasoning behind it?
Old 10-21-2008, 08:27 AM
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jacob711
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Default RE: Tuned pipe materials and band questions

im pretty sure any pipe will work fine but some pipes may work better on an engine because of the timings on it

yes steel pipes work better than aluminum, yes steel is louder but most steel pipes these days use an internal stinger which makes them quieter than most aluminum and don't lose any performance, and you can also put a muffler on to make even quieter

its not so much less bends but header length that matters, most headers like wrap to center style are too long to tune properly,
0 band pipes make more rpm, 1" and 2" band basically spread the power band more
Old 10-21-2008, 01:57 PM
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Default RE: Tuned pipe materials and band questions

Jacob711,
Thank you, I understand the material and banding part of it now.

When you say internal stinger, do you mean the stinger that protrudes from the pipe is actually also inside the pipe to make it quiet (do you have a manufacturer name) or do you mean the tuned pipe has a built over muffling system over the pipe to re-direct the exhuast gases before it exits out (this type I have seen and heard but just cant remember the manufacturer's name).

Any other input is well appreciated.
Old 10-21-2008, 08:01 PM
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jacob711
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Default RE: Tuned pipe materials and band questions

an internal stinger goes into the pipe to the center where the 2 cones meet
Old 10-21-2008, 10:23 PM
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Default RE: Tuned pipe materials and band questions

Thanks Jacob711...
Old 10-22-2008, 12:27 AM
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Default RE: Tuned pipe materials and band questions


ORIGINAL: jacob711

an internal stinger goes into the pipe to the center where the 2 cones meet
The tuned pipes outlet stinger is only a pressure regulator. By having it on the end of pipe it bleeds off the gas's pressure at the point of maximum amplitude [:@]

By moving this bleed off point to the biggest diameter section of pipe you get less noise because it is the place within pipe having the least amplitude
Old 10-22-2008, 08:32 AM
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Default RE: Tuned pipe materials and band questions

how much power loss can we expect from external stinger vs.internal sting (same pipe same header just external vs. internal stinger)i ask because i am buying a qd deep vee pipe soon and am very interested to know oh and do you lose any power useing a muffler any help would be great
Old 10-22-2008, 10:32 AM
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Default RE: Tuned pipe materials and band questions


ORIGINAL: lawnmower man

how much power loss can we expect from external stinger vs.internal sting (same pipe same header just external vs. internal stinger)i ask because i am buying a qd deep vee pipe soon and am very interested to know oh and do you lose any power useing a muffler any help would be great

No power difference, just noise.
Old 10-22-2008, 02:01 PM
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Default RE: Tuned pipe materials and band questions


ORIGINAL: lawnmower man

how much power loss can we expect from external stinger vs.internal sting (same pipe same header just external vs. internal stinger)i ask because i am buying a qd deep vee pipe soon and am very interested to know oh and do you lose any power useing a muffler any help would be great
Here's an answer that from Redline Motors that replied to my quetion of about those QD pipes:

On a dyno the external shows more power. On the water we dont see any difference! The internal has a lot more torque.

Old 10-22-2008, 10:00 PM
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Default RE: Tuned pipe materials and band questions

Scott,
Are these internal stingers perforated like a muffler or is it a solid tube that extends mid point. As well, are these wet pipes or hot pipes? Would you care to give a manufacturer's name and particular pipe model please?
Old 10-22-2008, 10:21 PM
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Default RE: Tuned pipe materials and band questions

im not Scott but i can help you

internal stingers are simply a tube with no holes in it except at the back there is a small hole so you can drain water out if you flip or whatever and the pipe gets filled up

i never really see wet pipes being used at all because they don't give as good performance as dry/hot pipes and i don't think water would work too well because it wont be able to escape properly in an internal stinger setup and it will end up in the engine

many manufacturers use internal stingers, heres a few

http://www.cc-racingengines.com/inde...e17514f4c91546

http://www.insaneboats.com/index.php...b6e03a952e5c78

http://www.redlinemotors.us/#/pipesa...tpa/4521241598

also you could add an internal stinger to you current pipe if you want, you just need some brass tube that slides into your current stinger and jb weld it in but don't forget a water drain hole, you may lose a bit of performance depending on the stinger size though because it may be too small in diameter
Old 10-22-2008, 11:53 PM
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Default RE: Tuned pipe materials and band questions


ORIGINAL: 01VIPER27

Scott,
Are these internal stingers perforated like a muffler or is it a solid tube that extends mid point. As well, are these wet pipes or hot pipes? Would you care to give a manufacturer's name and particular pipe model please?
Jacob has pretty much spelled it for you.

The R&D of the "Internal Stinger" was done in the 1970's by Gordon Jennings who wrote the "Two Stroke Tuners hand book"
While this info was well supported by the R&D of the time in 2 stroke tech, it has is some degree been further tweaked to fit the technology of a more modern time.

His research in the dynamics of the "Internal Stinger" tho has withstood the test of time and only within the past few years has been looked at again.

** The internal stinger can be applied in a basically two ways ...
One being applied at the location of a conventional stinger, the end of the convergent cone.
Second being it is threw the side of the pipes wall near the maximum diameter.

Either version vents away the gas's at pipes maximum diameter where the amplitude of the pressure wave activity is minimal.
Old 10-22-2008, 11:59 PM
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Default RE: Tuned pipe materials and band questions


ORIGINAL: Scott Schneider


ORIGINAL: 01VIPER27

Scott,
Are these internal stingers perforated like a muffler or is it a solid tube that extends mid point. As well, are these wet pipes or hot pipes? Would you care to give a manufacturer's name and particular pipe model please?
Jacob has pretty much spelled it for you.

The R&D of the "Internal Stinger" was done in the 1970's by Gordon Jennings who wrote the "Two Stroke Tuners hand book"
While this info was well supported by the R&D of the time in 2 stroke tech, it has is some degree been further tweaked to fit the technology of a more modern time.

His research in the dynamics of the "Internal Stinger" tho has withstood the test of time and only within the past few years has been looked at again.

** The internal stinger can be applied in a basically two ways ...
One being applied at the location of a conventional stinger, the end of the convergent cone.
Second being it is threw the side of the pipes wall near the maximum diameter.

Either version vents away the gas's at pipes maximum diameter where the amplitude of the pressure wave activity is minimal.

And NO, the tube that go's internal is UN-PERFORATED only having a small @ 1/8" hole at end of convergent cone so water can be drained.


** Tho note: As the internal stinger is made longer than the conventional stinger, it's internal diameter must be made larger because of it's greater length. ( this being relative in providing equal flow and back pressure )
Old 10-23-2008, 12:00 AM
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Default RE: Tuned pipe materials and band questions

Edited as duplicate post
Old 10-23-2008, 12:32 AM
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Default RE: Tuned pipe materials and band questions

Just for general info, here's a test I did a few months ago on the same day. I used my 60" Titan mono, well used stock G260 engine, one piece steel pipe (no internal stinger) with a 2814/3 chopper prop. The boat weighs in at 10 kilos or 22.5 pounds.

Full dry pipe, 15800 rpm @ 75 kph
Semi wet pipe, 15300 rpm @73 kph
Wet pipe, 14800 rpm @ 70 kph

1000 rpm and 5 kph difference which was not noticeable on the water.

Using just the one water pick up in the rudder, water goes through the cylinder jacket, then the exhaust cooling block then straight out the water outlet for a full dry pipe set up. Running the boat with this set up and the engine cover on produces an excessive amount of heat or hot air inside the boat which is detrimental to overall performance in a short period of time. Maximum speeds can't be maintained for long periods and acceleration is very poor once heat has built up.

Semi wet uses a "T" piece between the cooling block and water outlet. From the "T" another hose connects to the exhaust pipe through a 10/32 nipple where the header meets the front cone. This allows pipe pressure to dictate water flow into the pipe. At low speeds, maximum water flow is achieved for good cooling of the pipe and at high speed, less flow for better performance. This is the best set up by far for overall performance when running with the engine cover on.

A full wet pipe uses all available water flow directly into the pipe from the engine and cooling block instead of it going through the water outlet. This set up works very well, I just found that the "semi wet" pipe gave a little better performance without the excessive heat build up that is generated from a dry pipe. The header part of the pipe does retain a lot of heat but does not effect performance at all as it has far less surface area than the rest of the pipe being cooled.
__________________________________________________ ____

I tested my new 65" catamaran again last weekend with a new stock G260, semi wet pipe and 2614/3 chopper. This boats weight in at 11.5 kilos or 26 pounds. It ran 72 kph @ 16400 so don't think that stock engines can't rev or that wet/ semi wet pipes don't perform. Yes, a dry pipe is still the best for all out performance but are better suited to open cockpit boats where as all my models, monos and catamarans are fully cowled in.

Cheers, Danny.
Old 10-23-2008, 01:17 AM
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Default RE: Tuned pipe materials and band questions

Every motor and setup will vary your results. Our HT motors do not like the internal stingers. Our HR style motors see no differance with internal or external.

This is something too keep in mind with all the different mod style Zens out there. Some may like it and some may not. From what we hear from customers they notice no differance with internal versus external on Zens.

Todd

Quickdraw
Old 10-23-2008, 02:11 AM
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Default RE: Tuned pipe materials and band questions

There is really much to learn and absorb here.

Clearly a "0" Band Steel Dry Pipe with a straight or 90 header is the choice (tuning the pipe to a particular engine or mod is another thread). The CC Racing Pipe is looking good at the moment coupled to a J&G's modded engine (which will have to wait).

To all who replied, I thank each and everyone of you for the knowledge you have shared. Keep the thread alive as I am sure there will be better things to come as the years pass on from people like you to learn from.

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