The Definitive "don't swap in a VVT motor with a stock ECU" non-Megathread
#1
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That is a big IF because I do not. I am running on stock 94 ECU.
Car starts, but dies immediately, I presume because the ECU doesn't see a signal from the coils to confirm it is running.
Car starts, but dies immediately, I presume because the ECU doesn't see a signal from the coils to confirm it is running.
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I thought I remembered it was the same dwell and others had done this on stock ECU without issue. I am now half into this and need to figure out the finish so I can have a running car again.
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Why stand alone? This is a NA daily driver. Not FI. Budget daily driver. Been running great on stock ECU, WHY stand alone? Makes no sense to me. I guess I will go back to 94 coils until I have time to figure out the wiring.
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I don't know, maybe running a box made for a 8.8:1 motor with a 10:1 motor might not be the greatest idea in the world. I mean, you have literally nothing to gain outside of torque and power and not blowing up your motor, but you seem to have it all figured out.
#10
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There is no "figuring out" the wiring - your stock '94 ECU will never drive the tachometer in the absence of the coils.
If you want to continue the discussion within the scope of the stock ECU, start another thread. This thread assumes that you're using a standalone, as stated in the original post.
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^I wouldn't be surprised that some folks have attempted to run their VVT swap, at least initially on the stock ECU, who were unaware that it flat-out won't run for more than a second. That would be good information to put in the sticky.
In my case, I needed a replacement engine, and it just so happened, a VVT was available locally, for a good price. Luckily for me, I already has an MSPNP in the car. If I only had the stock ecu, and bought the engine, I'd have been out of luck.
C
In my case, I needed a replacement engine, and it just so happened, a VVT was available locally, for a good price. Luckily for me, I already has an MSPNP in the car. If I only had the stock ecu, and bought the engine, I'd have been out of luck.
C
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The wide band shows a perfect AFR everywhere but idle where it is a little lean. Car runs GREAT on stock ECU. I wonder if the VVTuner can give me the signal I need?
The stock 94 ECU runs the VVT engine perfectly. I am using a VVTuner to control the VVT functions.
The stock 94 ECU runs the VVT engine perfectly. I am using a VVTuner to control the VVT functions.
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I do not believe that the VVTuner will output a proper tach signal. I can believe that a stock 94 ecu with VVTuner could run a VVT engine in a way that would be safe and fun to drive on the street. Yes a standalone may be able to get a better tune, but if you are not tracking the car or driving it extremely hard I doubt you would have any problems with stock ecu and VVTuner.
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The stock ecu runs the VVT engine perfectly. And, I drive it very hard in the mountains spending many hours above 6K.
Lars, I am already putting the 94 coils back on, Thanks!
I will see if I can find the dyno run from a dyno day, not sure if they printed the AFR's or not. Either way, I don't care. The car runs great and has been seen doing so by many at several of the miata gatherings in the area.
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Dude calls me a liar with no evidence at all that what I say is false? I guess we know who was bottom this morning! Don't be a dick ![Thefinger](https://www.miataturbo.net/images/smilies/thefinger.gif)
The stock ecu runs the VVT engine perfectly. And, I drive it very hard in the mountains spending many hours above 6K.
Lars, I am already putting the 94 coils back on, Thanks!
I will see if I can find the dyno run from a dyno day, not sure if they printed the AFR's or not. Either way, I don't care. The car runs great and has been seen doing so by many at several of the miata gatherings in the area.
![Thefinger](https://www.miataturbo.net/images/smilies/thefinger.gif)
The stock ecu runs the VVT engine perfectly. And, I drive it very hard in the mountains spending many hours above 6K.
Lars, I am already putting the 94 coils back on, Thanks!
I will see if I can find the dyno run from a dyno day, not sure if they printed the AFR's or not. Either way, I don't care. The car runs great and has been seen doing so by many at several of the miata gatherings in the area.
I do not believe that the VVTuner will output a proper tach signal. I can believe that a stock 94 ecu with VVTuner could run a VVT engine in a way that would be safe and fun to drive on the street. Yes a standalone may be able to get a better tune, but if you are not tracking the car or driving it extremely hard I doubt you would have any problems with stock ecu and VVTuner.
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