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Old 03-03-2011, 09:05 PM   #1
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Default Question about the Boost control FET

HI All,

I've busted the IRLZ44 Fet included in the kit.
Can I use one of the Injection Fets from the MS build kit?
I used the 4 channel injector board from jbperf so have 2 x IRFIZ34GPBF Fets kicking around.

The difference is the boost Fet has a continuous drain current of 50A and 150W versus 20A and 70W for the other one.

Will the GM solenoid pull that much current?

It will be for testing, I will probably replace it with the right part in the near future.

Cheers
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Old 03-04-2011, 01:08 PM   #2
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If you're going to replace it anyway and it's just for a test . . . why not? The frequency for EBC is quite a bit lower than needed for fuel injection, so I don't see any issue there.
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Old 03-04-2011, 01:14 PM   #3
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worth a shot. you could even try a tip120 if you had one.
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Old 03-04-2011, 01:49 PM   #4
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Yes but the IRFZ34 will run a bit hotter due to its higher "on" resistance.
GM boost solenoid actually pulls less current than the injectors. (~100 mA vs 1A)
If the IRFZ34's are capable of driving the injectors with the same or less heatsinking than the original boost FET, then they will be more than capable of driving the solenoid.
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Old 03-04-2011, 02:41 PM   #5
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One other thing to keep in mind - the IRLZ series has a logic level gate; the IRFIZ version is designed around a 10 volt gate voltage...
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Old 03-06-2011, 03:09 PM   #6
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Thanks for that guys.
Would the 10V needed be as simple as a 5V pull up on the gate signal?
If not then I might just use a TIP 120.
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Old 03-06-2011, 08:03 PM   #7
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5V is enough to drive an IRFZ134 to drive a boost solenoid. Make sure whatever is driving indeed goes all the way to 5V, and not 4V or 3.5V.
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Old 03-06-2011, 08:48 PM   #8
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cool, I will test this later on tonight then.
Will update with result for the benefit of others.
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Old 04-30-2011, 03:23 PM   #9
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And, does it work with the IRFIZ34?
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Old 05-01-2011, 10:18 AM   #10
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Oops forgot about this thread.

Yes it does work with the IRFIZ34, but i currently drive it with a TIP120.
I killed the MS2 chip modding it for seq injection (well it died after i did the jumpers, ws working fine on batch) and changed the V3 board back to MS1 for a chip I had laying around, so the IR got used an an injector driver again.

The GM solenoid felt smoother with the IR vs the TIP transistor, strange but it almost felt like a dampened (filtered) operation.
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