oldevodude

iTrader: (3)

According to Ohms law the resistor is put in place IMO to more closely match the stock coil resistance(/reluctance/inductance) other factors to consider and thus will reduce the load seen by the voltage potential/output from the ecu and limit the current draw to be similar to the stocker. By having a higher total series resistance (than not running resistor) divided by the voltage that will give us the amount of current that is drawn from the ecu output. Any way it sounds like some of us might already know this.


I'm not trying to argue with anyone but as far as losing resolution at higher frequencies rpm's this would only be of significance if the inductor (coil) is actually used in a L-C circuit configuration kinda like a passive crossover in a loudspeaker system where we have a basic coil placed in series or parallel with a loudspeaker and the inductance rating of the coil and whether or not a resistor and capacitor are wired series or parallel determines the crossover frequency, and slope not to mention which musical frequencies ultimately pass to the particular speaker and at what magnitude.

We control the duty cycle by adjusting the table in the rom i suppose someone with an oscilloscope could measure the ECU output and see if it changes with different total resistive/inductive loads... My guess is the frequency is controlled by a PWM (pulse width modulated circuit/timer within the ECU)

Oh well thought I would throw it out there "none the less"

LOL been 2 lazy to put my GM bcs on

PS looking forward to your boost control mod Dave

Jack_of_Trades

iTrader: (17)

Well, a solenoid type coil has totally different characteritics than a basic cross-over coil does but I agree that the frequency shouldn't be affected at all. The crossover coil worls by inductance where the solenoid coil is more of a magnetic field. The faster the magnetic field can be switched on or off, the faster its response is. The issue is the lower voltage which will hinder response time causing different latency results which might be less than optimum for the GM 3port. It is most certainly a PWM scenerio.

mchuang

iTrader: (11)

Port size was 1/8th npt on the thread and 1/8 on the barb, the same as the gm solenoid. Also same size vaccuum hose.

oldevodude

iTrader: (3)

Agreed about the coil usage as a solenoid uses it's coil windings to create a electromagnet that in this case controls an air valve. I'm sure the windings are many and are small gauge to handle the constant cycling of the solenoid. Contrast to this a power door lock which is designed for single push and and pull

I do not think the amount of voltage would affect the operating speed as long as the voltage is sufficient to cause the solenoid movement which it does then at higher duty cylces it simply performs the same movement due to whatever voltage (lower in the case of resistor) is applied (pwm )until a more constant voltage is applied (100% duty cycle) the solenoid remains in a constant state to direct air flow in the case of this particuar application. The oscillation is so fast that the solenoid can no longer cycle or remains in it's charged state.