Pipefather,


A tune pipe would typically supercharge an engine by 20%....
So getting 5,000-10,000 RPM, as you were already told by others, is very much out of the question!

Getting 1,000 RPM more, as in, say, 14,000 instead of 13,000 RPM, would require nearly 25% more HP and 16% more torque, at the higher RPM.

Spinning the same propeller at twice the RPM, requires eight (8) times the HP. And even this is correct only at tip-speeds of non-compressibility (up to roughly Mach 0.7).
At higher Mach numbers it becomes very much higher.

...You obviously never tested, or observed, back-to-back testing of normal and tuned exhaust systems on an engine, so please allow others that are experienced with this to express themselves and bring yourself to listen to them.


A good tuned exhaust will typically increase VE and torque by 15-20%, over the open-exhaust numbers and by about 25-30% over a regular silencer (RPM by 10-15% higher).
An outstandingly great tuned exhaust (like those of F2B racers and nitro boats, spinning 30-40,000 RPM), can achieve up to 27-30% over the open-exhaust VE numbers.

Believe this, or you are bound to be extremely disappointed...