drewcrew6

Does anyone know the formula to design a tuned pipe? Everything I can find is set to the size of engine and you plug in a bunch of stuff and presto here's your pipe.
Looking for either the math or something that allows you to change engine size.

Thanks
Drewcrew6

ophirw

Hi drewcrew6 ,

1st i recommend you read about the expansion chamber & Kadenacy effect that is relevant to 2 stroke engines (Wikipedia is a good place to start)

there is a software that you can input all the info including the engine size: http://www.buildandclick.com/index.html
the problem i found is that all the software design a strait exhaust system for motorbikes as appose to RC cars where you don't have enough room for a strait system & you need to arch it to fit it into the car (just like the tune pipes are) this reduces the efficiency of the system.

on this page you will find all the mathematical theory with detailed explanations: http://microcarproject.tripod.com/ht...gn_softwar.htm

i would really like to hear what you are planning on building or modifying, so please keep me posted.

drewcrew6

Thanks Ophriw
I will check that out on Wiki. That software looks good but won't be using it enough to pay for it. Probably one time use. The last link looks good to now i just need to figure out what i need to do to make that code snippet run.
All I want to do is make a tuned pipe for a ryobi 30cc engine and see how much more i can get out of this engine.

Thanks
Drewcrew6

savagecommander

look up java pipe

Mudgy

Boat guys use this

http://www.modelpowerboat.com/Tuned_Pipe_Designer

Old school theory in here

http://edj.net/2stroke/jennings/2str...rshandbook.pdf

drewcrew6

Thanks Mudgy

I came across that before but at the top it says about 8.2-14.3 cm3. So I am assuming it won't work for a 30 cc engine. Is that a bad assumption? Or is there a way to change the engine size that I am missing?

NEVERMIND I started playing with it and what do ya know the engine size changes with input changes. Now I need to get all the timing off my engine.

Thanks
Drewcrew6

da mad maori

from memory the 30cc ryobi engines have rev limiters built into the ign....... if so you might wanna adapt another coil to fit