<HTML>Does anyone know how to make an exaust silencer? I tried an experiment with one that I make with a plastic soda bottle. I did work, but not as well as I would have liked. I drilled holes around it in different places, at even increments (about 5.5cm apart).
I figured the distance for the holes based on the speed of sound (1100ft/s) divided by the frequency (same as rpms), all divided by 2 (so you get the half wave cancelation). It did make it quiter at low rpms, but at high speed it made no difference.
I figured it for 3000 rpms, but the diameter of the bottle is bigger then the diameter of the muffler. So the speed of sound will change when it hits that area.
Doesn anyone know how to calculate the correct hole size, and position?</HTML>