Make Formula Racing Exhaust

When a camshaft timing and overlapping periods of dimensions increases, the need for more specific exhaust neck becomes a necessity. High duration cam will cause some unexpected things at a certain RPM, and a proper exhaust design will minimize this problem. We certainly want to work in harmony with the exhaust camshaft as, especially at high engine speeds, to maximize the release of exhaust gases from the cylinder.
Means not only do we have to connect the exhaust lip has the right angle of the exhaust ported, but also we must be good at determining the diameter and length of the fitting. Of course the best place to do this experimentation is to raise the motor on the machine dynotest. However, it is possible to produce exhaust fit our expectations if we understand the principle of 'exhaust tuning' and the basic rules of high-performance exhaust air.

The size of the diameter of the pipe will help the speed of the exhaust gas through the exhaust. Large diameter pipe, relative to the size of the cylinder, the gas velocity will decrease. Because a machine would create peak torque at a gas velocity of about 75 meters / second, the header pipe on the exhaust will affect how the peak torque RPM will be. So the larger exhaust pipes will shift the peak torque produced approaching limiter.
Changing the length of the exhaust will help increase the engine power curve around the point of maximum torque. Adding exhaust pipe length will increase the area under ke- middle RPM, and peak power at maximum RPM will be drained. Short pipe will be members of high-speed power, medium power with reduced compensation.
With these factors in mind, it will be important early before entering the calculation. Here is the formula to determine the length of the exhaust pipe:
L = {(850 x ET) / MAX RPM} - 3
L = length of the exhaust pipe to be made
ET = Exhaust Timing, when the exhaust valves begin to open up before the TMB
MAX RPM = RPM dimau to get the peak power
example:
Jupiter started my racing exhaust opening timing to 80 degrees before BDC, then the calculation is
L = {(850 x 260) / 10,000} - 3
L = 19.1 inches = 485 mm
Then we'll exhaust pipe diameter determines the required =
D = sqrt (CC / ((L + 3) x 25)) x 2.1
D is the diameter of the pipe is desired
CC is a cylinder capacity
L is the length of the exhaust
Then the diameter of the exhaust pipe for my Jupiter is:
D = sqrt (171 / ((19.1 + 3) x 25)) x 2.1
D = 29 mm
Easy anyway ...
So I need to exhaust Jupiter with a capacity of 170 cc and 310 degrees duration Noken is 48.5 cm long by 2.9 cm in diameter in the pipe so that the engine produces power at 10,000 RPM.