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Finished mocking this up

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Finished mocking this up

PostAuthor: bbqb4racin » Sun Nov 26, 2017 9:21 pm

The worst is over! BTW, this will NOT see wrap!

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Re: Finished mocking this up

PostAuthor: Hellgate » Sun Nov 26, 2017 10:06 pm

Looks great! I'm looking forward to hearing a sound clip.

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Re: Finished mocking this up

PostAuthor: briandk » Tue Nov 28, 2017 7:40 am

I see a lot of exhausts go to great lengths to make the front pipe as long as the rear one, often resulting in some weird designs. Your's looks really great, probably one of the nicest designs I've seen even, but did you consider the impact of them being unequal? Googling it I find everything from that they must be the exact same length, to that it doesn't matter.

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Re: Finished mocking this up

PostAuthor: Flyingdog » Tue Nov 28, 2017 7:58 am

Not an expert of exhaust systems. Other than length/diameter/packing (if any)/routing/configuration..2 > 1..2 > 2 etc, will directly effect air/fuel charge readiness for the big bang. Lot of info. May answer some questions.

https://www.hotbikeweb.com/tech/exhaust ... cs#page-11
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Re: Finished mocking this up

PostAuthor: faffi » Tue Nov 28, 2017 9:38 am

V8s rarely have equal length headers, yet tend to make good power still. Sometimes, I've seen unequal length headers used to widen the powerband at the cost of a little bit of top end power.

https://www.youtube.com/watch?v=RWTARjxiqlo

https://www.youtube.com/watch?v=Y7_lSU3D0jw

https://www.youtube.com/watch?v=azPKIjxmmdU
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Re: Finished mocking this up

PostAuthor: Flyingdog » Tue Nov 28, 2017 2:00 pm

How ironic...saw couple those while back.
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Re: Finished mocking this up

PostAuthor: bbqb4racin » Tue Nov 28, 2017 5:55 pm

I take many things into consideration when I do a build. Sometimes looks, fitment and style may win out over performance. Considering this is a low horsepower, mediocre performing bike as it is, 1-2 HP here or there really doesn't concern me. It will run fine and should sound good when I'm done.
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Re: Finished mocking this up

PostAuthor: Flyingdog » Tue Nov 28, 2017 6:41 pm

No doubt. One only has to look at it's well thought out. I offered up the link in response to briandk.
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Re: Finished mocking this up

PostAuthor: bbqb4racin » Tue Dec 26, 2017 11:05 pm

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Re: Finished mocking this up

PostAuthor: Flyingdog » Wed Dec 27, 2017 2:33 am

Wow-Nice!
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Re: Finished mocking this up

PostAuthor: nanno » Wed Dec 27, 2017 7:38 am

briandk wrote:I see a lot of exhausts go to great lengths to make the front pipe as long as the rear one, often resulting in some weird designs. Your's looks really great, probably one of the nicest designs I've seen even, but did you consider the impact of them being unequal? Googling it I find everything from that they must be the exact same length, to that it doesn't matter.


Having built a metric sh*t-ton of exhausts for the TR1: Yes, equal length headers help quite notably. There is a certain room for error though. So my front and rear downpipes on my 2-1-2 are within of a few milimetres and compared to some previous designs where the lengths of the downpipes easily varied by 40-50mm (overall length is about 700mm) the loss in torque is quite notable. One COULD intentionally make the headers different lengths and thereby boost performance at certain rev-ranges, but even though I did the maths I could only partially get it right and stuff tends to get very, very tricky, when you try to outsmart the rules of physics.

Cheers,
Greg
http://viragotechforum.com/viewtopic.php?f=12&t=43227 - Nanno's accumulated findings (and blatant show-off) - infos on my TR1's, my performance and reliability mods and a bit of show-casing of the stainless steel exhausts I build

http://greasygreg.blogspot.co.at (My blog - Greasygreg.blogspot.co.at)
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Re: Finished mocking this up

PostAuthor: benpineapple » Tue Feb 27, 2018 3:55 pm

hey bbqb4racin, what did you use for the header's flange? does the 1 3/4 pipe just butt right up to head, or does it have a thick ring at the end like the stock headers?
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Re: Finished mocking this up

PostAuthor: bbqb4racin » Tue Feb 27, 2018 6:09 pm

benpineapple wrote:hey bbqb4racin, what did you use for the header's flange? does the 1 3/4 pipe just butt right up to head, or does it have a thick ring at the end like the stock headers?


I recycled the stock flanges. I did open them up a bit but the rings and flanges are from the stock pipes.
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Re: Finished mocking this up

PostAuthor: faffi » Wed Feb 28, 2018 5:13 am

nanno wrote:Having built a metric sh*t-ton of exhausts for the TR1: Yes, equal length headers help quite notably. There is a certain room for error though. So my front and rear downpipes on my 2-1-2 are within of a few milimetres and compared to some previous designs where the lengths of the downpipes easily varied by 40-50mm (overall length is about 700mm) the loss in torque is quite notable. One COULD intentionally make the headers different lengths and thereby boost performance at certain rev-ranges, but even though I did the maths I could only partially get it right and stuff tends to get very, very tricky, when you try to outsmart the rules of physics.

Cheers,
Greg


I am not going to question your experience in any way, I just wonder what makes for instance the MAC 2-1 apparently work quite well, and also the stock system, as both have greatly different header lengths.
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Re: Finished mocking this up

PostAuthor: nanno » Thu Mar 01, 2018 7:21 am

faffi wrote:I am not going to question your experience in any way, I just wonder what makes for instance the MAC 2-1 apparently work quite well, and also the stock system, as both have greatly different header lengths.


Question EVERYTHING and ALWAYS! :bg:

The MAC works quite well until you put a restrictive muffler on from my personal experience. The stock one works (I think), because the rear muffler has got a secondary outlet just for itself and the scavenging setup on the Y-pipe is quite well thought out. The gains with a less restrictive system are quite notable though. (Also when gut the innards of the stock silencers (rust did that for me), a performance increase was quite notable, even without any other modifications.)

Cheers,
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http://viragotechforum.com/viewtopic.php?f=12&t=43227 - Nanno's accumulated findings (and blatant show-off) - infos on my TR1's, my performance and reliability mods and a bit of show-casing of the stainless steel exhausts I build

http://greasygreg.blogspot.co.at (My blog - Greasygreg.blogspot.co.at)
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Re: Finished mocking this up

PostAuthor: faffi » Thu Mar 01, 2018 8:56 am

So that may explain why my 1100 ran so well when still sitting in the stock chassis - basically, it was running on the headers alone as the collector was just about vanished.
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Re: Finished mocking this up

PostAuthor: nanno » Thu Mar 01, 2018 10:48 am

Pretty much, yes. One of the things I learned the hard way over the last few years when building exhausts is that the minor flaws in exhaust design only show up, when you add some restriction to the mix. Even bad designs will flow surprisingly well if there's nothing much in the way. Only when you're starting to work towards scavenging and joining exhaust pipes for this matter, you will see some differences.
http://viragotechforum.com/viewtopic.php?f=12&t=43227 - Nanno's accumulated findings (and blatant show-off) - infos on my TR1's, my performance and reliability mods and a bit of show-casing of the stainless steel exhausts I build

http://greasygreg.blogspot.co.at (My blog - Greasygreg.blogspot.co.at)
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Re: Finished mocking this up

PostAuthor: faffi » Thu Mar 01, 2018 2:58 pm

Good to know :thanks:
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