Tuned Pipe Question
jaxson
08-09-2003, 09:10 PM
Hey everyone,
I bought a Yokomo polished tuned pipe and i installed it on my hpi rs4. I didn't buy a new header or anything but i jsut attached it and I cut it down so that its now tuned. But now i have to cut a bog hole on the side of the body inorder to slip the body over. Is that normal? It looks very weird.
I bought a Yokomo polished tuned pipe and i installed it on my hpi rs4. I didn't buy a new header or anything but i jsut attached it and I cut it down so that its now tuned. But now i have to cut a bog hole on the side of the body inorder to slip the body over. Is that normal? It looks very weird.
EMAXX
08-09-2003, 09:25 PM
Yeah, there should be a little hole for the exahust pipe to come out of. Its normal.:smile:
jaxson
08-09-2003, 10:05 PM
No, I mean there is a big chunk of my RC's body which is cut out. Like an 1 1/2 inch by 1 1/2 inch wide. Not only does the stinger stick out but also the converging part of the pipe. The area where the metal wire is tightened to. I guess a big help is if you have or know any place with reference pics of a HPI RS4 RTR with a yokomo polished tuned pipe so i can see if i did anything wrong.
God|Zilla168
08-09-2003, 11:55 PM
I still don't understand what you are trying to say. Maybe if you took a pic of the problem.
Also there are two kinds of yok pipe one is for the 1/10 and the orther is the 1/8 did you get the right one.
Just checking
Also there are two kinds of yok pipe one is for the 1/10 and the orther is the 1/8 did you get the right one.
Just checking
jaxson
08-10-2003, 09:12 AM
I don't have a web page so i can't post the pics online. Do you have an e-mail address so that i can mail it to you?
God|Zilla168
08-10-2003, 10:25 AM
check your pm
Jonno
08-12-2003, 06:11 AM
www.automotiveforums.com/upload
Use the img tags around the URL and it should work.
Use the img tags around the URL and it should work.
jaxson
08-17-2003, 09:29 PM
Thanxs for the suggestion Jonno. I forgot about that feature. Well here are the pics. Hope u guys can help me. I want this pipe to fit in well so i can buy a HPI Saleen S7 body to put on.
http://files.automotiveforums.com/uploads/398987RC1.jpg
http://files.automotiveforums.com/uploads/818167RC2.jpg
http://files.automotiveforums.com/uploads/711143RC3.jpg
http://files.automotiveforums.com/uploads/398987RC1.jpg
http://files.automotiveforums.com/uploads/818167RC2.jpg
http://files.automotiveforums.com/uploads/711143RC3.jpg
God|Zilla168
08-17-2003, 10:43 PM
You got the wrong set of headers on the car. Go to your hobby store and ask them for the right header. Think is time for you to upgrade your engine too.
jaxson
08-18-2003, 02:02 PM
Oh ok, well what suggestions do you have for me for a new engine? When i get my new header, do i have to retune my pipe and cut it?
God|Zilla168
08-18-2003, 05:13 PM
For one you don't have to cut anything inorder for it to fit.
Fot a .12 engine either a novarossi or rb engine depends on if you want roar legal or not. Some are ported etc. Do a research I own rb concepts on my car and I would recommend these. But they are expensive.
Fot a .12 engine either a novarossi or rb engine depends on if you want roar legal or not. Some are ported etc. Do a research I own rb concepts on my car and I would recommend these. But they are expensive.
jaxson
08-19-2003, 12:39 AM
I know i dont have to cut anything to refit it. I'm asking if i have to cut the pipe inorder to retune it. I've done testing and my pipe is cut to a certain length so that my RC runs at its peak performance. But if i get a new header, that will lengthen or shorten the distance the exhaust has to travel, therefore it would make sense for me to recut the pipe, but i could be wrong.
God|Zilla168
08-19-2003, 02:53 AM
I don't know who told you to cut your pipes inorder for your engine to run at peak performance. For your engine to run well you need to tune your idle screw and not cut your length of the pipe. So if you cut your pipe chances are you need to get a new pipe.
may I ask who told you to do that or did you just thought cutting the pipe short will give you better performance?
may I ask who told you to do that or did you just thought cutting the pipe short will give you better performance?
jaxson
08-20-2003, 06:13 PM
The guy at HobbyTownUSA said to and i did some research online which told me to. http://www.quicktechhobby.com/articles/name_that_tune.htm
"However, some engine tuners will go so far as to cut material off the header pipe (in small increments of 1/8" to 1/4") in search for the "ultimate" tune. This is recommended only for experienced racers with the proper tools."
"However, some engine tuners will go so far as to cut material off the header pipe (in small increments of 1/8" to 1/4") in search for the "ultimate" tune. This is recommended only for experienced racers with the proper tools."
Jonno
08-22-2003, 09:12 AM
may I ask who told you to do that or did you just thought cutting the pipe short will give you better performance?
I can see the sence in cutting the lenth of the pipe. If the pipe is shorter, there is less of a distance for the exhaust to run out of, so an smoother flow. See how most racing cars have shorter exhausts that lead out the side underneath the door?
I can see the sence in cutting the lenth of the pipe. If the pipe is shorter, there is less of a distance for the exhaust to run out of, so an smoother flow. See how most racing cars have shorter exhausts that lead out the side underneath the door?
2000-redrider
08-26-2003, 02:45 PM
Here's some info taken from www.nitrorc.com:
"The construction of the tuned pipe works with the pressure pulses coming out of the exhaust port. The pulses resonate inside of the pipe and travel back into the manifold. The pressure pulse actually pushes the air/fuel mixture that escaped out the manifold back into the combustion chamber. This super-charges the combustion chamber and gives the 2-stroke engine its characteristic peak HP. This is the point in which the engine turns ON. You will know that you hit this point because the car will accelerate rapidly when the engine gets on the pipe. You can actually fine-tune when the engine will have this extra burst of power. The speed at which the pressure waves from the pipe synchronizes with the piston, is a function of the length from the belly of the tuned pipe (widest part) to the center of the glow plug. The longer the distance, the faster the engine will come on the pipe. If you want to delay the time when the engine hits the supercharge, then shorten the header and/or pipe. When you replace the stock header/manifold, keep in mind that there is a reason for a pipe's size and geometry. You can use this information to your advantage to strengthen your engine's power band. A bad decision in the exhaust department can actually lower engine performance. "
Personally, if you find that you need to shorten the distance of your exhaust I would only cut the header. This is becuase the shape of the pipe is part of it's tuning. Change the shape and you'll change it's tuning characteristics.
"The construction of the tuned pipe works with the pressure pulses coming out of the exhaust port. The pulses resonate inside of the pipe and travel back into the manifold. The pressure pulse actually pushes the air/fuel mixture that escaped out the manifold back into the combustion chamber. This super-charges the combustion chamber and gives the 2-stroke engine its characteristic peak HP. This is the point in which the engine turns ON. You will know that you hit this point because the car will accelerate rapidly when the engine gets on the pipe. You can actually fine-tune when the engine will have this extra burst of power. The speed at which the pressure waves from the pipe synchronizes with the piston, is a function of the length from the belly of the tuned pipe (widest part) to the center of the glow plug. The longer the distance, the faster the engine will come on the pipe. If you want to delay the time when the engine hits the supercharge, then shorten the header and/or pipe. When you replace the stock header/manifold, keep in mind that there is a reason for a pipe's size and geometry. You can use this information to your advantage to strengthen your engine's power band. A bad decision in the exhaust department can actually lower engine performance. "
Personally, if you find that you need to shorten the distance of your exhaust I would only cut the header. This is becuase the shape of the pipe is part of it's tuning. Change the shape and you'll change it's tuning characteristics.
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