errors when logging with usb interface

160 And 8192 Baud Aldl
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Re: errors when logging with usb interface

Post by Jervies »

Yep non resistive plugs and leads.
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Jayme
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Re: errors when logging with usb interface

Post by Jayme »

yeah non resistive plugs and leads are a massive source of interference. thats why EFI cars swapped to resistive leads and resistive plugs. see if you can find a set off a later engine you can borrow to test maybe? I wonder would 304 leads and plugs fit a chev?
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Re: errors when logging with usb interface

Post by Dylan »

The plugs fit an LS1 if that helps.
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Re: errors when logging with usb interface

Post by antus »

Can anyone explain how around 3 ohms of resistance in the spark plug makes so much difference despite usually more than 2k resistance in the lead? I know it can but it just doesnt add up to me. Say 2500 ohm vs 2503 total..? Havnt measured this for a while but i believe those figures arent too far off.
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Re: errors when logging with usb interface

Post by vlad01 »

soild wire is very low induction and resistance, therefore it flows current at a much higher and at a much faster rate. That means larger and sharper magnetic flux is produced = strong electromagnetic field.

Modern leads are spiral wound wire aka induction core wires. As the induction of a spiral core lead is much higher than a solid copper core it takes a lot longer for the flow full current to reach 5t so the electromagnetic interference is much much less. Spark plugs are also resistive for similar reasons except I think its about limiting current and developing a larger voltage drop across the plug, that also benefits interference production.

Pretty much also why we don't make antennas out of resistors or inductors and rather from solid conductors as you do want to make a strong electromagnetic field.
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Re: errors when logging with usb interface

Post by vlad01 »

Looks like the resistance of the plug has a lot to do with it. It basically forms an LR circuit and determines the length of the time constant. The longer the time constant the less the intense the radio pulse will be.

http://www.electronics-tutorials.ws/ind ... cuits.html
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Re: errors when logging with usb interface

Post by Jervies »

Well we tested the setup out on the weekend, running at a local street drag meet, wasnt much traction but still run consistant 95mph and worked perfectly all day.
So next step, nitrous control :driving:
How would one go about setting up a time based table and about pulling timing with the 11p? Im thinking map switch or shorting map out, but unsure about time based table
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Re: errors when logging with usb interface

Post by Holden202T »

the main thing is you beat the ford :P hehe

my brother and I have dabbled a bit with nitrous control with $12P using flex tables, but I'm not sure how you can do it based on time, certainly RPM or road speed you could do if you have a speedo connected to the computer.
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Re: errors when logging with usb interface

Post by Jervies »

Sorry guys i posted this in the wrong thread, im yet to test the resistor plugs but i used the usb comms on a supercharged vn 5lt the other day and it worked well so must be the setup in the car.
Holden202T i dont have a speed input yet but that would certainly work
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Re: errors when logging with usb interface

Post by Holden202T »

the only problem with speed is if you get wheel spin it can flare and then activate etc, but I guess it can give you another level of control, we always planned to use speed for activating a second stage of nos once in second gear etc.
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