MicroSquit Conversion, Giving this a try |
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MicroSquit Conversion, Giving this a try |
Mblizzard |
Oct 3 2016, 07:18 AM
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#1
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
I am pretty happy with my stock FI. But after seeing some of the setups at Okteenerfest, I thought this might be worth trying.
The stock system is not easy to modify and get things running correctly. I spent a lot of time making minor adjustments by trial and error. While I am not looking for huge HP gains or anything, it is pretty clear that the mods I have could potentially benefit from a bit more precise control. Going to start with fuel only at this point to get things going and see where it leads me. Any help or suggestions for set up would be appreciated. |
Dtjaden |
Oct 7 2016, 02:12 PM
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#2
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Member Group: Members Posts: 232 Joined: 25-May 13 From: Morgan Hill, CA Member No.: 15,915 Region Association: Northern California |
I appreciate all of the intelectual comments. I am afraid they will most likely confuse the OP. If he simply find follows the recommendation in the Megasquirt/Microsquirt manuals all will be good.
By the way 2.0 injectors check out at slightly less than 2.5 ohms when cold. |
N_Jay |
Oct 7 2016, 02:57 PM
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#3
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Member Group: Members Posts: 283 Joined: 2-March 16 From: Chicago NW Burbs Member No.: 19,720 Region Association: None |
I appreciate all of the intelectual comments. I am afraid they will most likely confuse the OP. If he simply find follows the recommendation in the Megasquirt/Microsquirt manuals all will be good. By the way 2.0 injectors check out at slightly less than 2.5 ohms when cold. I see where the manual talks about the resistors slowing down the opening. I am not sure the peak and hold would be as good as building a constant current driver (or is the engineer in me over designing?) Maybe just put a capacitor across the resistor? |
Dtjaden |
Oct 7 2016, 05:10 PM
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#4
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Member Group: Members Posts: 232 Joined: 25-May 13 From: Morgan Hill, CA Member No.: 15,915 Region Association: Northern California |
I appreciate all of the intelectual comments. I am afraid they will most likely confuse the OP. If he simply find follows the recommendation in the Megasquirt/Microsquirt manuals all will be good. By the way 2.0 injectors check out at slightly less than 2.5 ohms when cold. I see where the manual talks about the resistors slowing down the opening. I am not sure the peak and hold would be as good as building a constant current driver (or is the engineer in me over designing?) Maybe just put a capacitor across the resistor? The reason for a peak and hold driver is that it provides a burst of current to open the injector and then drops the current to a lesser level that keeps the injector open. You get the best of both worlds - fast opening and lower average current. A capacitor across the resistor would do the opposite of what is needed, it would slow both the opening and closing. |
N_Jay |
Oct 8 2016, 07:20 AM
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#5
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Member Group: Members Posts: 283 Joined: 2-March 16 From: Chicago NW Burbs Member No.: 19,720 Region Association: None |
I appreciate all of the intelectual comments. I am afraid they will most likely confuse the OP. If he simply find follows the recommendation in the Megasquirt/Microsquirt manuals all will be good. By the way 2.0 injectors check out at slightly less than 2.5 ohms when cold. I see where the manual talks about the resistors slowing down the opening. I am not sure the peak and hold would be as good as building a constant current driver (or is the engineer in me over designing?) Maybe just put a capacitor across the resistor? The reason for a peak and hold driver is that it provides a burst of current to open the injector and then drops the current to a lesser level that keeps the injector open. You get the best of both worlds - fast opening and lower average current. A capacitor across the resistor would do the opposite of what is needed, it would slow both the opening and closing. The Peak and Hold gets high owning current and low average holding current by PWM the signal. Not a bad solution as long as the PWM does not let the injector start to close. I don't see how a capacitor across the resistor would slow the opening or closing? Sized correctly, it would bypass the resistor for the initial inrush, and then as it charged the resistor would be the primary current limit. As for closing, I would have to give it some more thought. (Been a while since I did any circuit design work) |
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