Driving Solenoid Valve (Re: Electronic Boost Control)

[avos at cochlear.com.au]

     I recently emailed about driving a solenoid valve for an electronic 
     boost controller and have worked out how to drive it power wise, but I 
     have another question in regards to such a valve.
     
     The valve is a 12V solenoid valve with a 3.2mm orifice. It is rated to 
     handle 60 psi. It is called a 'pulse' valve and is designed to be a 
     ble to handle PWM signals. I plan to drive it (using a MOSFET) from a 
     MC68HC705B16 which has a PWM output, however the minimum frequency 
     32768 times slower than the external clock speed, so for a 2.45MHz 
     osc, my minimum PWM frequency is 75 Hz. Is this PWM frequency feasible 
     for a mechanical solenoid valve driven by a 12V coil. I have tried to 
     get specs from the manufacturer for the maximum frequency 
     ofmoperation/ min switching time etc, but they do not have such 
     ratings. Can anyone advise me if 75Hz duty cycled modulated PWM(which 
     implies switching speeds much quicker since the duty cycle may become 
     1%, so effective min switching frequency is about 7.5 kHz) is too 
     quick for a sloenoid valve. If someone has used similar valves 
     previously, I would appreciate it if I could find out what frequency 
     they were clocked at?
     
     Adrian