For those that purchased a Multi-Spark Ignition to cure a problem.

[onefstsnake]

1. Rich Condition at higher rpm's 11.9:1 A/F

2. MSD 6AL, MSD Blaster II Coil and MSD 2 Step

3. Runs alot cleaner @ idle, and smoother up top.

4. More Wires... Also the increased spark output means replacing cap/rotor sooner.

5. Smaller Box...

 

[caseywan]

Get it to run smoother and stop the bucking of the car when cruising at low speeds.

Crane HI6s

Yep, ran much much smoother and no more bucking at all, and much nicer idle!

No problems that I am aware of.

No complaints about it so far.

 

[Rick 91GT]

Andy, I'm back in town if you want to try giving me a shout again.

The Jacobs system is nice but I like the Digital Series stuff from MSD.

 

[fiveohwblow]

Using an ignition rev limiter in a boosted application is not a good thing.

My tuner has no problems with it and neither does my car... I am confused
Why is it a bad thing?

 

[onefstsnake]

Dont most Ignition boxes (MSD, Crane, Jacobs.) cut spark for their limiters?

This shouldnt hurt anything. You wouldnt want it to cut fuel and cause a lean condition.

 

[Daggar]

Dont most Ignition boxes (MSD, Crane, Jacobs.) cut spark for their limiters?

This shouldnt hurt anything. You wouldnt want it to cut fuel and cause a lean condition.

This is myth for our cars. Again... the A9x family does not create lean conditions by reducing fuel to the cylinder. It shuts fuel off COMPLETELY to every other cylinder. No lean condition exists.



onefst and casey... those are the kinds of things I'm looking for. Real problems or improvements that a multi-spark ignition solved for you. Thanks!


fiveohwblow... bounce a well boosted application off an ignition rev limiter until you get backfire through the intake. That's what can happen when you retard timing enough in a boosted app to prevent the engine RPM from continuing to climb.

 

[fiveohwblow]

This is myth for our cars. Again... the A9x family does not create lean conditions by reducing fuel to the cylinder. It shuts fuel off COMPLETELY to every other cylinder. No lean condition exists.

fiveohwblow... bounce a well boosted application off an ignition rev limiter until you get backfire through the intake. That's what can happen when you retard timing enough in a boosted app to prevent the engine RPM from continuing to climb.

I see. Forgive me for being ignorant, but I understand our engines run more like a 4 cycle. That being said, your saying when spark is taken away and fuel still applied, it will build up and be ignited upon re-ignition and cause a larger boom than needed? Thank you for your expertise!

 

[Daggar]

Not in all cases... There is a "sweet spot" but that spot is a hell of a lot easier to find and maintain on a normally aspirated car than it is one that is force inducted.

 

[onefstsnake]

But how does the MSD A9X box shut off fuel to every other cylinder when its not wired to anything related to the injectors?


Its wired to the Coil and thats about it.

 

[86bluecobra]

onefst and casey... those are the kinds of things I'm looking for. Real problems or improvements that a multi-spark ignition solved for you. Thanks!

I guess he didn't like my post.

 

[Daggar]

But how does the MSD A9X box shut off fuel to every other cylinder when its not wired to anything related to the injectors?


Its wired to the Coil and thats about it.

The MSD box doesn't do anything of the sort. It's the Ford EEC that has the fuel rev limiter. It's an issue (and mentioned here) because many people believe that the fuel shutoff in the Ford EEC is bad for boosted applications because they 'think' that it reduces fuel to the cylinders and causes a lean condition. It does not. Instead, it shuts the fuel injectors off for every other cylinder. The rev limiter that your MSD uses is an ignition rev limiter. Those are the types that can wreak havock on a boosted application. It only take one good backfire through the intake (and blower) to cause some serious damage.

 

[Daggar]

Couldn't tune nitrous the way I wanted.
I purchased my digital 6 box.
Yes it allowed me to adjust my timing retard function.
Yes my factory Tach would not work. I had to buy a tach adabter to fix that problem.
If I had to change something it would be that it would work with factory tach's. it seems silly to have to wire in another product to use factory equipped tach's.

86bluecobra -

I missed one... thanks for the info.

 

[Busted07]

This was about 3 years ago, but as far as the Jacobs stuff, a friend of mine and i put an Allen Engine Development supercharger on his 4.6 Thunderbird. He went through 3 Jocobs boxes, and they all failed the same way each time.

He swapped everything over to MSD and hasnt had a problem since.

 

[1990Coupe]

This was about 3 years ago, but as far as the Jacobs stuff, a friend of mine and i put an Allen Engine Development supercharger on his 4.6 Thunderbird. He went through 3 Jocobs boxes, and they all failed the same way each time.

He swapped everything over to MSD and hasnt had a problem since.

yea i second that - i had a buddy that went thru 2 jacobs box's before he switched to MSD and hasnt had a problem since.

sorry daggs to hijack - ive had driveablility issues and idling issues and stalling issues with my stang, i wonder if an ignition would solve it? im running stock ignition with 36lb injectors, 80mm mass air, 70mm throttle body and a 255lb pump. i wonder if im fouling out the plugs? could it be possible?

 

[Daggar]

I don't think that you're actually fouling the plugs but rather not getting the ignition event you need at the time you need it with our single spark, stock ignition.

In other words:

Your ignition is lighting off the combustion mixture in the cylinder but it's (perhaps) not occurring at the ideal time in the cylinder stroke.

I believe that to be very similar to what I'm seeing with by combination as well. It's something that these multi-spark systems are supposed to cure. Instead of just one chance to light off the combustion mixture, it's supposed to provide half a dozen or so, chances for the mixture to ignite and burn optimally. Moreover, it's supposed to be able to light off several "start points" for the combustion mixture to burn more evenly during an ignition event (the idea being that a single ignition spark and one burning start point for the mixture may not be enough to provide for a complete burn as the burning event cascades out over the whole combustion mixture).

Needless to say, I've done a lot of reading about the reasons for Multi-Spark ignitions over the last week or so. I've been concentrating a lot more on the multi-spark events than I have on actual spark energy.

Our symptoms seem to be pretty similar and I'm beginning to accept that perhaps the multi-spark events may be the cure (as opposed to merely increasing spark energy or intensity).

 

[1990Coupe]

I don't think that you're actually fouling the plugs but rather not getting the ignition event you need at the time you need it with our single spark, stock ignition.

In other words:

Your ignition is lighting off the combustion mixture in the cylinder but it's (perhaps) not occurring at the ideal time in the cylinder stroke.

I believe that to be very similar to what I'm seeing with by combination as well. It's something that these multi-spark systems are supposed to cure. Instead of just one chance to light off the combustion mixture, it's supposed to provide half a dozen or so, chances for the mixture to ignite and burn optimally. Moreover, it's supposed to be able to light off several "start points" for the combustion mixture to burn more evenly during an ignition event (the idea being that a single ignition spark and one burning start point for the mixture may not be enough to provide for a complete burn as the burning event cascades out over the whole combustion mixture).

Needless to say, I've done a lot of reading about the reasons for Multi-Spark ignitions over the last week or so. I've been concentrating a lot more on the multi-spark events than I have on actual spark energy.

Our symptoms seem to be pretty similar and I'm beginning to accept that perhaps the multi-spark events may be the cure (as opposed to merely increasing spark energy or intensity).

So your having similar issues as me? I also get terrible gas mileage, and people who ride behind me relay to me a really bad gas/exhaust smell, way more of a smell then any other mustang around here running an O/R exhaust setup similar to mine. Ive also had one time where the car flooded on me and i had to wait a while and then she fired up. The more i think about it, and now im researching too, i think i could have a spark issue. This is something i never really considered.

 

[Metalcop]

-The problem I bought my ignition to solve was a small 'hiccup' or stumbling at low rpm, post supercharger install.
-I purchased the Crane HI-6 ignition, supposed to be superior to the MSD.
-The new ignition did not solve the aformentioned problem.
- No other problems were created, though I do get a fair amount of radio noise 'clicking' at lower rpms.
-I would not change anything with the system, necessarily. I purchased the timing retard option, but I chose not to use it (For sale!), going with a PMS instead. The rubber mounting insulators I received were junk. I mounted by box on the passenger side fender, and the inserts pulled out of the rubber after 1 stinking day! I had to fabricate my own out of rubber bungs/plugs where the mounting bolts go all the way through.

ps. Obviously the reason for the 'hiccup' is a lack of fuel, not quite fast enough when the accelerator is depressed quickly. Hopefully a full fuel delivery upgrade, and the PMS will take care of it!

 

[Daggar]

That's the first time I'd heard anyone say that the Crane was supposed to be superior to the MSD. I'd always understood it as the cheaper alternative. It's not able to support the current or spark intensity that the MSD is and is limited to 8000 RPM on 8 cylinder engines where the MSD is supposed to support 10,000 RPM. The MSD is also supposed to provide a hotter spark and multi-spark capability up to 3000 RPM.

I'm assuming we're talking about the Hi-6S?

MSD:

Operating Voltage:..........+10-18 VDC Negative Ground
Current Requirements:....5 Amps-5,000 RPM
......................................10 Amps-10,000 RPM
RPM Range:.....................15,000 RPM with 14.4 Volts
Spark Duration: ..............20° Crankshaft Rotation ~ multispark to 3000rpm on 6 series 3300 rpm on 6+
Energy Output Max:........105-115 mJ Per Spark
Weight and Size:.............3 lbs, 8"Lx4"Wx2.25"H
Voltage Output Max:.......Primary: 460-480 Volts
Secondary:.....................45,000 Volts (Blaster Coil)

Crane:

Operating Voltage:............6 to 18v, reverse polarity protected, negative ground
Current Draw:....................5.0 amps max. at 7,000 RPM
RPM Operating Range:.......8,000 RPM (can be extended to 10,000 RPM
..........................................on 4 cylinder engines)
RPM Limiter Range:............3,100 to 9,900 RPM when digital stage rev
..........................................limiter mode selected.
Multiple Spark Duration:....Approximately 20 degrees crankshaft rotation below
......................................... 2,000 RPM. Max 12 sparks per sequence.
Primary Voltage Output:....450 volts (inductive discharge)
Spark Duration:.................2,800 microseconds at 2,000 RPM
Trigger Input:....................Module trigger (12v square wave)

It appears that the spark produced by the MSD is hotter and that the multi-spark function operates for an additional 1000 RPM.


Here's another question though... I see that the MSD requires another "box" so that you can feed the stock tachometer. I've looked at the wiring for the MSD 6 series and that doesn't make sense to me. Where exactly, is the stock tach getting spark signal from? What I mean is... I'd always thought that it got it's feed from the wire going to the coil. The MSD appears to get it's signal from that same wire so why would you need to feed the stock tach differently after installing the MSD?

 

[onefstsnake]

The MSD 6/6AL do not need a separate box on 89-93 cars.
The adaptor harness has you plug the stock coil plug into the new harness which then connects to the coil.

Everything gets signal, without anything extra. Maybe the Digital 6 is different?

 

[Metalcop]

Believe me, I am not stating that the Crane is a superior unit, to the MSD. When I purchased mine, all of the Crane written propaganda stated that it was the better unit, more voltage, better duration blah blah blah. The main reason I went with the Crane was durability. Tons of users, on this forum even complain about the MSD units crapping out on them. This is probably an issue with MSD selling so many more systems than Crane, you hear about more of the problems?!