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Exhaust/tuned pipe building anyone?

Discussion in HPI Baja Engine and Exhaust forum, started by RCmru.

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  #1  
Old 04-12-2010, 06:59 PM
RCmru RCmru is offline
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Exhaust/tuned pipe building anyone?

Hi guys,

Has anyone tried to make his own pipe? Any guidelines to follow? Any plans (CAD design or such) that could be followed? Any raw materials to choose from?

It would be interesting to hear if anyone has ever tried to build his own tuned pipe/exhaust and what was the outcome.



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Old 04-12-2010, 07:29 PM
baja5bss baja5bss is offline
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i know there is software on the web you can find for 2-stroke pipe design. You need to make sure you have the correct volume for the application and other factors. I have seen it but havent looking into it much, sorry.
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Old 04-12-2010, 07:50 PM
Rallyfinnen Rallyfinnen is offline
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There are a few guys here building pipes. turboglenn is one of them.
There is just as much 'witchcraft' involved in the pipes as the porting i think.. Nobody wants to disclose all the tricks they learned over the years, but I think you can make some decent pipes by using software or formulas from tuning books.
It's all there, but you need to invest the time to read, understand and experiment.
I think it takes quite some tinkering and testing to make it suit your engine and driving style, but then you will have a pipe that is just right for you!
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Old 04-12-2010, 07:51 PM
RCmru RCmru is offline
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Quote:
Originally Posted by baja5bss View Post
i know there is software on the web you can find for 2-stroke pipe design. You need to make sure you have the correct volume for the application and other factors. I have seen it but havent looking into it much, sorry.
Thanks! I'll do my research using the info you provided
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Old 04-12-2010, 07:53 PM
RCmru RCmru is offline
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Quote:
Originally Posted by Rallyfinnen View Post
There are a few guys here building pipes. turboglenn is one of them.
There is just as much 'witchcraft' involved in the pipes as the porting i think.. Nobody wants to disclose all the tricks they learned over the years, but I think you can make some decent pipes by using software or formulas from tuning books.
It's all there, but you need to invest the time to read, understand and experiment.
I think it takes quite some tinkering and testing to make it suit your engine and driving style, but then you will have a pipe that is just right for you!
It's like the Coca Cola recipe The right formula won't be disclosed...

I'll see what I can found then. Should be fun to see how this can be achieved.
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Old 04-12-2010, 08:01 PM
turboglenn turboglenn is offline
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it's a long and involved process, read the 2 stroke tuners handbook, you can google it or there's links on here. the doftwares out there always seem to come up with numbers that are rediculous or even negative measurements from some. this is because most wont' do engines under 50-100cc's and there's one that does them as small as 30cc but the measurements still come up way off.

The only decent program i've ound is MoTa and it's quite expensive, but it can simulate the speed of sound in your pipe given the specs of everything and guide you along prety well, then there's the java-pipe applet that give reasonable numbers (just search for "java-pipe) or you can find links to it on model gas boats .com

I make all my own pipes and make them for others as well and it's quite the process, be prepared! there's no CAD or anything because you need to form the cones out of raw sheet metal by laying them out on paper, tracing them and then cuttign from sheet metal and folding and welding it.

i know i'm sounding discouraging it's just that i'm in a rush to get to work, but seriousely read the books, the softwares out there are pretty far off for engines this small and only give rough sizes that sometiems are wayh inccorect.
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Old 04-12-2010, 11:28 PM
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Eric Hill Eric Hill is offline
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pipe

I have designed and built all of my pipes. And yes they run different than when they are cones than stamps.
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Old 04-12-2010, 11:41 PM
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MCRIPPPer MCRIPPPer is offline
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i have wanted to try this too, but i have never really reserched it much. read 2stroke tunners handbook. it has some great info.


now a question. sre their any more good 2 stroke info links anyone has on building pipes?
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Old 04-12-2010, 11:50 PM
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Eric Hill Eric Hill is offline
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Pipes

When you buy a program to build pipes it goes into all the details of the engine before you can design your pipes. I say pipes because you will end up making many before you come up with a design/performance you like.
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Old 04-13-2010, 01:50 AM
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strada001 strada001 is offline
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Quote:
Originally Posted by turboglenn View Post
it's a long and involved process, read the 2 stroke tuners handbook, you can google it or there's links on here. the doftwares out there always seem to come up with numbers that are rediculous or even negative measurements from some. this is because most wont' do engines under 50-100cc's and there's one that does them as small as 30cc but the measurements still come up way off.

The only decent program i've ound is MoTa and it's quite expensive, but it can simulate the speed of sound in your pipe given the specs of everything and guide you along prety well, then there's the java-pipe applet that give reasonable numbers (just search for "java-pipe) or you can find links to it on model gas boats .com

I make all my own pipes and make them for others as well and it's quite the process, be prepared! there's no CAD or anything because you need to form the cones out of raw sheet metal by laying them out on paper, tracing them and then cuttign from sheet metal and folding and welding it.

i know i'm sounding discouraging it's just that i'm in a rush to get to work, but seriousely read the books, the softwares out there are pretty far off for engines this small and only give rough sizes that sometiems are wayh inccorect.

well, just my 2 cents...

TurboGlenn build my pipe... and also did the MODD on my CY 30.5...
the bad part is.... because of LOTS of changes that my life is going thru right now I don't even have the time to play with my baja, let alone work on it.

well, I just hope things will turn to the better by mid MAY.

see y'all guys.
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Old 04-13-2010, 02:23 AM
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carvet929 carvet929 is offline
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My brother and I built a couple. We made them a little long for bottom end. They are ugly pipes, but it made a inprovment in grunt over the only other pipe i had , which was a jetpro.
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Old 04-13-2010, 03:07 AM
Sprint 77 Sprint 77 is offline
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I have been building and modiing pipes for other less available large scale for several years. There is the math and programs as spoken above and also a little of trail and error. A sound wave resonotor meter is cool for tuning also but is a old meter t hat is hard to find. My friend has one think he got it at a HAM radio trade show.
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Old 04-13-2010, 03:07 AM
Sprint 77 Sprint 77 is offline
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A good Tig welder and lots of sheetmetal experience helps out in the fabbing process too.
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Old 04-13-2010, 03:20 AM
turboglenn turboglenn is offline
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Thing is running the programs on these small engines comes up with measurements that are pretty much useless

but doing the math by hand or calculator will give good results
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Old 04-13-2010, 07:53 AM
RCmru RCmru is offline
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This is very interesting to read the views of those who have tried.

It appears that, if I wish to try out, I will need to find some free time to experience the whole process.

Thanks.
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Old 04-13-2010, 08:12 AM
JariV JariV is offline
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I've made my pipes also. Also made them for others. There is a world of difference to commercial pipes when one hits the sweet spot.

Don't rely entirely on calculators like MOTA. As said here the pipe building is usually a trial and error process after calculations. DON*T expect to get it right the first time. Be prepared to build several pipes instead of one. One will only tell you something, several different pipes start giving you a perspective and instincts on where you need to go with the next pipe.
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Old 04-13-2010, 09:45 AM
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Eric Hill Eric Hill is offline
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Quote:
Originally Posted by JariV View Post
I've made my pipes also. Also made them for others. There is a world of difference to commercial pipes when one hits the sweet spot.

Don't rely entirely on calculators like MOTA. As said here the pipe building is usually a trial and error process after calculations. DON*T expect to get it right the first time. Be prepared to build several pipes instead of one. One will only tell you something, several different pipes start giving you a perspective and instincts on where you need to go with the next pipe.
This is the truth. The books, programs only get close. There is no program or book that can replace good old trial and error of real world testing.
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