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wickedsnake00
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EEC-V COP Transistor Current Limit

Post by wickedsnake00 » Tue Oct 06, 2020 12:11 pm

Does anyone know the current limits (or part number that would allow a lookup) of the transistors used to drive the ignition coils in the later EEC-Vs? I'm looking to see just how much current they can handle for ignition coil upgrades.

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cgrey8
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Re: EEC-V COP Transistor Current Limit

Post by cgrey8 » Tue Oct 06, 2020 2:31 pm

Just out of curiosity, what's the difference in DC-resistance between the OEM coils and the coils you are intending to use?

I'm assuming the primary coils would be similar in size and the higher-winding-count secondary coil will be where we get the higher voltage from...but that's purely a guess. This strategy would require a higher dwell (coil charge) time.

However if they went the route of a smaller primary coil, this could reduce the DC-resistance and increase the current flow into the coil in order to bump up the output voltage AND keep dwell time the same.

What I don't know is how much dwell is affected and if it is enough to matter for them to modify the primary coil and risk damaging factory EECs. I'd think they would not make a physically plug-n-play coil that would be harmful to OEM devices. Perhaps that's a bad assumption since that's exactly what they did with low-impedance injectors.
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wickedsnake00
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Re: EEC-V COP Transistor Current Limit

Post by wickedsnake00 » Tue Oct 06, 2020 8:29 pm

I don't have the values offhand for resistance, but I've been eyeing up the Audi R8 coils as an upgrade over the stock 4V coils. From what I've found online, they have about the same dwell time as the Ford ones, around 2ms. That's a big advantage given I haven't found a way to adjust dwell in the tune for those strategies. The big difference is the Ford coils are 7A, and the Audi ones are a whopping 15A. From what I've seen the WeaponX drop in aftermarket coils draw a little over 12A, so the ECU should at least be capable of that.

Of course the R8 coils are also "smart" coils that could be driven via a 5V signal if the current demand exceeds the capability of the factory transistors. That could be achieved using another layer of transistors and the stock harness, or in the cleanest (but riskiest) approach, effectively bypassing the coil transistors and instead of the processor 5V signal driving the stock transistors within the ECU, going out on the coil signal wires to drive the transistors in the smart coils.

motorhead1991
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Re: EEC-V COP Transistor Current Limit

Post by motorhead1991 » Sat Oct 31, 2020 5:15 pm

wickedsnake00 wrote: Tue Oct 06, 2020 8:29 pm I don't have the values offhand for resistance, but I've been eyeing up the Audi R8 coils as an upgrade over the stock 4V coils. From what I've found online, they have about the same dwell time as the Ford ones, around 2ms. That's a big advantage given I haven't found a way to adjust dwell in the tune for those strategies. The big difference is the Ford coils are 7A, and the Audi ones are a whopping 15A. From what I've seen the WeaponX drop in aftermarket coils draw a little over 12A, so the ECU should at least be capable of that.

Of course the R8 coils are also "smart" coils that could be driven via a 5V signal if the current demand exceeds the capability of the factory transistors. That could be achieved using another layer of transistors and the stock harness, or in the cleanest (but riskiest) approach, effectively bypassing the coil transistors and instead of the processor 5V signal driving the stock transistors within the ECU, going out on the coil signal wires to drive the transistors in the smart coils.
I had this same idea with the transistors on the 2.3s, using the 5V from the TPS circuit and a ground trigger from the coil and a set of P-channel mosfets.
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BrodVictor
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Re: EEC-V COP Transistor Current Limit

Post by BrodVictor » Thu Apr 22, 2021 2:48 am

Hi....I bought a cluster of substitution capacitors a while back yet still can't seem to do any fixes yet. I certainly spec'd the 105C parts and increased the 16V parts to 25V, leaving the other one at 63V.

I had intended to bundle up my extras and offer them yet need to really a few fixes first.

order pcb

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