POWER PIPE. Hand built and tuned from scrap

Jayraye39

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So on a quest to build a tuned pipe or just a better pipe. I have taken 3 different expansion chambers and hacked them up. Im going to use the part that best fits my calculations off each pipe. combine them to make an overall better expansion pipe.. However when i cut open the nasty jack I was more than shocked at what I found.

If you own a nasty jack they are a very good pipe for the money. However you could be getting more power the nasty jack and may not even know it.

When I cut the stinger off right before the mounting tab I discovered that their were multiple different dia. tubes inside one another. They did this to reduce the cone down to a smaller hole for the exit of the stinger. This robs power because it not only traps the exiting exhaust gases but it also will not give a proper reverse pulse for scavenging.
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Next I cut open the center or belly of the pipe right where the joining weld was. What I found was even more shocking. The 2 cone halfs are folded inward to the inside of the chamber. Im guessing they did this because of the 3rd world welders they got building theses pipes. it allows them to get better penetration without burning through the 2 halves. However, This is very very restrictive. Not only does it create unwanted back pressure where you least need it. It also does not allow the pipe to act as an actual expansion chamber. Since the pulses travel against the pipe walls. It restricks the pressure wave leaving and returning to the piston.
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If you want more from your nasty jack and can weld or know someone that can. I would cut up your pipe and eliminate these trouble spots. I bet as soon as you bolt it on you will notice a big difference.

For myself im going to be adding a 4in wide middle section in between the 2 halves to make a nuetral dia. belly section. Im also going to be cutting my divergant cone in half and welding the end of the oxhorn expansion pipe onto it. it will give it a steeper angle and shorten the divergant cone. This will allow for a more powerful pressure return wave. Just hope i can get it their on time. lol.
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I have wondered what is inside of my MZ65 clones. Probably a world of nasty. One day I will take a piece of coat hanger wire and probe the inside.
 
I have wondered what is inside of my MZ65 clones. Probably a world of nasty. One day I will take a piece of coat hanger wire and probe the inside.
I wonder if they do something anything like this on seam welded pipes that go down the pipe instead of connect them together in the middle such as fat belly pipe or zdx65
 
Got my parts cut out and layed in order. The pile on the right is what i have left of the 3 chambers. What do yall think about the design? I have a good feeling this bike is gonna scream now.
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The 4in belly section needs to actually be a 2in section. Overal pipe length is 35in but needs to be around 33in. For scavenging fuel
 
The 4in belly section needs to actually be a 2in section. Overal pipe length is 35in but needs to be around 33in. For scavenging fuel
I have a stupid question I am not great with knowledge on the pipes but can you tune them to scavange more fuel then air and Vice versa Becuase there is a bunch of different designs so for pipes lol I know it’s mostly for it for different power bands but would that also include how it pushes the air fuel mixture
 
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