Wasted Spark Disadvantages?

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woodsbuggy1
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Wasted Spark Disadvantages?

Post by woodsbuggy1 » Thu Nov 20, 2014 9:42 pm

I will be starting a new build soon, 1915 with MS3x and Turbo. I have been very happy with the EDIS system on my 1776 with MS1 and turbo. I am planning to eliminate the EDIS module and still run wasted spark on the new motor(the 1776 will stay complete and be used in my street buggy) any good reason not to do this?
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Kenric
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Marc
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Re: Wasted Spark Disadvantages?

Post by Marc » Thu Nov 20, 2014 10:01 pm

Nothing I can think of that's worth losing sleep over. Two of the plugs will always be firing "backwards"; it takes more energy to make the spark jump from the relatively cool ground electrode than it does from the hot center one, but that's why they use overkill coils. The electrodes will erode differently too, but if you check the gap and swap the plug locations halfway through the lengthy replacement interval (100K miles isn't unrealistic) you can compensate for that.

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woodsbuggy1
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Re: Wasted Spark Disadvantages?

Post by woodsbuggy1 » Thu Nov 20, 2014 10:12 pm

Thanks for the input Marc,
This will be going in my offroad buggy which will receive new plugs at least once a year(after it is tuned). In the past I worked at an auto parts store and sold many COP coils but had not sold an EDIS Ford coil in over 10 years. I am convinced that the COP coils have a much higher failure rate than EDIS coil packs. I am far more interested in low failure rate than max power.
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Piledriver
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Re: Wasted Spark Disadvantages?

Post by Piledriver » Fri Nov 21, 2014 12:23 am

There's really no disadvantage if you are using EDIS coils or other coils designed for waste spark., and it saves a pair of outputs
There's nothing really wrong with EDIS at all short of the inability to cut spark, and no diagnostic/test capability.
Some late EDIS modules can even do multispark at <3K RPM.

If one wants to use say LS2 truck coils in waste spark mode, you can run out of dwell time over ~7K, and coil output will be reduced at high RPM due to that. For most folks this is never going to be an issue.
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Chip Birks
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Re: Wasted Spark Disadvantages?

Post by Chip Birks » Fri Nov 21, 2014 10:15 am

Sequential sounds cooler... :mrgreen:

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Re: Wasted Spark Disadvantages?

Post by Steve Arndt » Fri Nov 21, 2014 11:10 am

I run four IGN1 coils, but still run wasted spark. Running four coils (vs two doubled ended like EDIS) means all the plugs fire with the same polarity. Just to show there are always different ways to do things.

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Re: Wasted Spark Disadvantages?

Post by Clonebug » Fri Nov 21, 2014 9:03 pm

I have one season on my EDIS coil running direct fire with wasted spark and have had no issues.

Why buy another coil when you already have one.......or more...... :wink: :lol: that will work.
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Re: Wasted Spark Disadvantages?

Post by Piledriver » Fri Nov 21, 2014 9:39 pm

(continued)
The only real ADVANTAGE of individual coils on a typical RPM range engine is if you have MS3 or some other ECU and a hairy level (of CR/boost) tune that requires (and allows) per-cylinder timing modifications, and per cylinder knock retard.

MS3 allows both per cylinder fuel and ignition trim, MS2E only supports per cylinder fuel trim currently.(and may lack memory room to add the feature)

On a motorcycle that spins well past 10K, COPS make total sense, if only due to dwell/duty cycle concerns with waste spark.
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woodsbuggy1
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Re: Wasted Spark Disadvantages?

Post by woodsbuggy1 » Sat Nov 22, 2014 12:04 am

Thanks for all of the great input. I plan to stay with wasted spark and will be using MS controlled EBC. I will not be running crazy boost, just 8lbs wastegate and 12 to 15 on demand. There are two reasons for me to upgrade from MS1; eliminate EDIS module and datalogging without laptop. Anything else that I should be looking at?
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Re: Wasted Spark Disadvantages?

Post by Piledriver » Sat Nov 22, 2014 12:45 am

Get the MS3 RTC and knock system modules too.

Costs more but having real time/date etc w/o laptop is essential for SDcard logging, it should be std.
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woodsbuggy1
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Re: Wasted Spark Disadvantages?

Post by woodsbuggy1 » Sat Nov 22, 2014 10:00 pm

Thanks Pile,
I had not considered the RTC but after seeing it I definitely want it. I will probably pass on the knock sensor though, with E85 and an intercooler along with low boost levels I hope to be ok. Any other thoughts? I am trying to get everything figured out so I can call Mario and order my new MS3X. :D :D
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Re: Wasted Spark Disadvantages?

Post by Piledriver » Sun Nov 23, 2014 3:16 am

The knock setup is pretty easy to add later if needed (DIY) the RTC is essential for your stated goals.
Get the fastest class 10 SDcard you can find, I can log ~400 hz on an only slightly reduced dataset.
(I'm still on a V2.2 board, even the V1.01 board works fine, just needs more HW hacks to use all the features)

You might consider gluing it in for vibration proofing (the sdcards connectors weren't designed for heavy vibration) BUT:
Downloading many large logs at 115200 bps over serial (or god forbid over bluetooth at ~12 speed) is a serious time suck.

Get a microsd with an SD adapter, and just lightly use a few tiny dabs of 5 minute epoxy to secure the adapter.
Then just pull the microsd. (put a tape loop on it)
(implies you have 2 SD>micro adapters or a microsd reader)

5 minute epoxy is highly useful for this sort of thing BECAUSE it is crummy glue
(that's also what makes Post-It notes useful, in a different way)
... the cheap epoxy dusts in seconds with soldering iron heat and basically will fall off.
I use a dab of it on all soldered wire>board connections as strain relief.

The size of the microsd (and a carefully placed bit of tape) makes it far less vibration sensitive, plus if the connection does flake, just replace the $2 adapter, rather than having to replace the socket on the MS3..
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woodsbuggy1
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Re: Wasted Spark Disadvantages?

Post by woodsbuggy1 » Sat Dec 20, 2014 10:40 pm

Thanks for all of the GREAT suggestions and info. I was starting to be afraid when I added up all of the cost of MS3X but then VeeDubNut came along and helped me. So now Mario will be doing some mods for me and I will have MS3X V3.57 on my offroad buggy and MS2V3.0 on my street rail. I will have a lot to learn next season.
Where do I find more info about data logging via SD card? I have been searching but not a lot of info.
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Re: Wasted Spark Disadvantages?

Post by Piledriver » Sat Dec 20, 2014 11:12 pm

TunerStudio can (eventually) suck it off over serial and automagically convert it, or load from a file off the SDcard plugged into the PC and do the same.
It will create a new file in your current project log dir with a name based on the time stamp.

They are "normal" log files once converted by TS: load into MLV and hit play.

You don't HAVE to log at 300-400 Hz to get useful logs, that data rate makes for huge files, fast.
(you can limit the size per file tho, and just pull the ones you want if you know the time stamp)
You can also pick and choose what you want to log on the SDCard.

As far as the menus and such, create a MS3 project and play with it, no hardware required to see where things are in the menus.
(There are LOTS of tabs/sub menus for MS3)
Search IN tunerstudio works too.

You can also have GPS data in the std logs (assuming you have a GPS)
I don't think that is available in the SDcard data, yet, perhaps if you have an IOXpander over CAN.

If you have not registered TunerStudio, I strongly suggest doing so when the hardware shows up.
It will still work, mostly, unregistered (totally usable) but some of the registered features are worth every penny in your time.
(The better serial comms options and VEAL (or whatever he calls it now) being the primary benefits)
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