I have experience with racing 2 strokes spanning 40 years. All of these engines required a head pipe of constant cross section having a volume of twice the cylinder volume before entering the muffler or expansion chamber. They produced 4-5 hp per c.i..
Since the R.C. engines operate in the same RPM range, can they benefit from using a tuned header pipe? The use of an expansion chamber would be precluded because of the narrow power band but would there be a benefit from a remote muffler. Thanks!!