Well, 17" pipe should require a diameter of 1,77" which is about the diameter of the intake valve in the GT head. The average airspeed in this kind of pipe does not seem to bee too dramatic with 0,045 mach, peak will be probably higher of course. It feels just little bit too small, maybe 2" will be the ideal compromise... and in reality the eigenfrequency goes always down due to damping effects so that the pipe can be somewhat shorter than calculated. So much to theory....
Ve = 0,000535 m^3
V = 0,005 m^3 305,1187205 in^3
di = 0,045 m 1,771653543 in
Ai = 0,001590431 m^2 2,465173416 in^2
L = 0,45 m 17,71653543 in
air_d = 1,225 kg/m^3
air_p = 101325 N/m^2
Freq. = 45,53450363 1/s 2732,070218 1/min
Q_pipe = 1,461657567 m^3
v_pipe = 15,31720341 m/s 0,045050598 mach