Plasma Ignition - Promo Parley or Pratical Power

[DavidVizard-GFN]

GFN Product Spotlight - Plasma Ignition

Promotional Parley or Practical Power

By

David Vizard

The ignition system business often seems to be a lot more about the flavor of the day than other segments of the performance industry. We have heard tech terms come and go with repeated regularity and the term ‘Plasma’ is hardly a new one. But what is Plasma? Essentially it is an energy source that is capable of generating such a high temperature that it starts to strip the electrons from the outer valance ring of the atoms of gas within the near vicinity. Be aware that this takes a lot of heat and that in turn means a lot of good old fashion wattage in the plug gap.

Plasma technology is something that I have tested in the past on a number of occasions. The brainchild of Ulf Arens, who currently lives in Germany and lectures on tech stuff at the University of Hamburg, Ulf has so many university and college qualifications he no longer bothers to go through the time consuming job of putting them after his name. On each of the previous occasions the product I was to test worked just as Ulf had claimed. On this occasion I got a call from Ulf giving me the low down on his new Plasma ignition that was being produced and sold by Okada Projects out of Mission Viejo California (949-583-7800). The conversation went something like this: “The unit makes a high temperature plasma spark and the chassis dyno tests done by JBA Racing in San Diego showed, on an ’07 4.6 Mustang, a 7 lbs-ft and 9 hp increase”.

Now let’s consider the forgoing for a moment. The ignition system on these new Fords is not a ‘make do’ deal. For a production vehicle it is about as high tech as they come and is hardly lacking in capability. Without wanting to cast any doubt on JBA Racing’s ability to conduct a dyno test these number look to be -- well, sort generous to say the least. But I do not dismiss them because the results I have had with other ignition upgrades from Ulf have, as I said earlier, done just what he claimed they would. All this brings me to one conclusion, I had better start looking for an ’05 or newer Mustang to do some testing on. The need for one also proved yet another nudge toward justifying why I should buy one of these three valve Mustangs for myself but that’s another story.

Basic Ignition Science.

To burn the charge of air and fuel as effectively as possible means delivering as much energy to the plug as possible up to the point of overkill. The question here is what is totally sufficient and where does overkill start? I have done a lot of ignition testing in my time and in almost every instance it seems that a bigger, fatter more aggressive spark produces better ignition. Sure I have come across some notable exceptions here. Two that come to mind are the ‘A’ Series Mini engine that powered the original Mini Cooper and the big block Chevy with a certain type of factory head (casting number escapes me for the moment but if you are into real high performance you are unlikely to use them). In both these instances I found that at first the combustion got better as the spark got better but after a point not that far up the scale in terms of spark technology and delivery all gains topped out. On the Mini engine it seemed that once we had a good strong spark that even lightening bolts would show no improvement. On the particular engine involved we went all the way to about 21/1 fuel air ratio’s before any sign of a lean misfire was experienced. But that’s not the norm it would seem – especially for the modern multi valve engines with limited mixture motion and a centrally located spark plug.

To better understand what we are dealing with here let us consider what a conventional high performance ignition delivers to the plug. A typical modern high performance ignition system (factory or aftermarket) that we might categorize as a grade ‘A’ system will dump between 40 to 50 watts into the plug gap. This will produce a spark that is typically around 3000 to 4000 degrees Celsius.

To create an extreme temperature plasma spark of the type we are calling for here requires a lot more wattage in the plug gap than is produced by a conventional ignition system. The problem is that once the voltage at the plug has risen to the point of breaking down the resistance at the gap we find that once it fires across the gap it becomes, to an extent, self canceling. The spark will fire across the gap but the fact it has ionized the gap means the resistance within the gap had dropped. The spark characteristics in this secondary ‘after burn’ phase are not conducive to lighting off the charge. The oscilloscope display seen below shows what happens here.

Seen here is a scope shot of a conventional spark. Only the high temperature spike, part A actually does anything toward igniting the charge. Part B is the low temp after burn part of the spark which does nothing to aid ignition but does contain about 85% of the energy delivered by the coil top the plug. It is this energy that the Plasma booster taps into.

From the scope display you can see that the better part of the energy available at the coil goes to non-effective output at the plug. What is needed here is some way to dump most or all of the coils output into the plug gap in the form of a higher temperature and consequently more effective spark. This can be done by optimizing in two main area’s. First there is room for substantial improvement because, as we have seen from the spark trace, a regular coil ignition system only effectively utilizes about 15% of the coils output. In other words what actually lights off the mixture at the plug was only about 15% of what the coil could have delivered. Secondly if the spark duration time can be shortened then for the same amount of energy at the plug gap the wattage goes up and along with that so does the temperature. Now you may question the consequences of cutting spark duration but consider this: the after burn of a conventional spark lasts probably 10 to 20 times that of the initial spark but because it is too cool it plays little constructive roll in actually lighting off the mixture. From this we can conclude that it is better to have a short high temperature spark than it is too have a longer lower temperature. Between these two factors the question is where is the best balance struck.

Quality of the shot here is not so good because of the difficulty taking such a shot. Left is a single spark from a high performance ignition. Right is same system boosted with a plasma box. In a marginal situation it does not take rocket science to figure which of these sparks is likely to work best.

The target here then is to produce a super hot super aggressive spark to see if that gets the job done better than a longer lasting but cooler spark. This is what the plasma ignition system from Okada Projects seeks to do. By shortening the spark duration and utilizing as much as 75% of the coils available output not only is the wattage and current flow to the gap dramatically increased but also, almost as a by-product, the system becomes ultra high frequency multi-sparking and delivers from 5 to as many as 12 super hot sparks before coil output drops below a critical level. The discharge time per spark is so fast that the spark temperature goes up to over 30.000 degrees and the wattage to about 1000 watts.

Testing Time.

This is the plasma ignition kit we are testing. In this instance the system upgrade consists of coils and a plasma box.





Shown here is the box that converts a regular spark to a plasma spark.

So far everything looks good on paper and from past experience with Ulf Arens designed products. Now it was time for us to see if we could replicate the JBA Racing results. But just before starting on our own tests I recalled tests from some time back from a reliable source (and I need to research this further) that one of Ulf’s Plasma units (which type/model I have yet to establish) on a 4V Mustang had turned in an average of 13 hp increase. That 13 hp was from a virtually stock engine supposedly originally producing about 260 rear wheel hp and that looks a lot for just an ignition swap but more on that later.

The intent here was not to test on something bordering exotica (as the less than common 4V engine would be) as it may give us a skewed picture of the situation. Because of the typically less than optimal mixture motion these 4 V engines have they appear a little more fussy over the spark quality given but guess what – how many of us actually drive a 4V Mustang? No – what we will look at here is the results seen from tests on a regular three valve Mustang GT. That’s what the majority by far of the 4.6’s are so results will be more meaningful. We will look at the 4 V stuff at the end of this feature and see how it might relate to 4V engines in general regardless of make and size. Right now let’s get to our dyno testing.

The dyno being used here is the Dynojet at Custom Performance in Charlotte, North Carolina. This is an up to the minute model Dynojet and I like to use it because of the type’s really good repeatability. Another factor is that so long as the bearings in the rollers are good and no one has messed with the system programs math equations the unit cannot produce wrong numbers. It’s all a question of the factory inputting the correct inertia for the rollers and presto – reliable hp numbers.

Our test car was one smart looking sweet running ’07 GT. It had already been outfitted with a K&N cold air package and an exhaust upgrade.

Like any test that may be looking for small differences we have to be sure that we start with a repeatable baseline. Two factors work for us here. Not only does the dyno repeat well but the engine delivered a consistent output one run to the next. The result was very small differences from one run to another. This means we can be sure the results are substantially real rather than the sum of experimental errors.

Here Sean (left) and Dale (right) hook up the unit. Installation of the plasma kit was fast and easy. Just follow the simple instructions.

Everything went smoothly, quickly and without drama. The results are as you see in the chart below.

The numbers to study are those in the yellow rows labeled TQ Diff and HP Diff. At low speeds there was mostly only a marginal increase with the plasma ignition but once the 3800 mark had been surpassed the gains were more than evident. Peak torque rose by 3.8 lbs-ft and, for a maximum, surpassed the 300lbs-ft mark – the first time this car had ever done that. The biggest torque gain was at 6200 where the number rose by 6.1 lbs-ft while the increase between 5000 and 6200 averaged 4.5 lbs-ft. By any standard these are creditably close to the results that JBA Racing got when they ran the test.

The test results that came off the ’07 Mustang and Custom Performance’s Dynojet dyno prompted me to look through past results achieved with previous Ulf Arens designed plasma systems. This would give me a statistical idea of how consistent results might be compared to the ones just seen. First a 5.0 pushrod Mustang. This was equipped with a cold air system, Walker mufflers and a Crane coil. Over the rpm range of 1300 to 5300 the average torque went up by 4.6 lbs-ft and the average HP by 2.8. When considering these numbers do not overlook the fact that the before test was run with a Crane coil which is among the best of the high perf ones available on the market today. So the plasma spark paid off here.

Next on the list was a 4.6 two valve modular motor. A before and after test from 1500 to 5800 rpm showed an average increase of 6.2 lbs-ft and 4.1 hp. A second 2 valve 4.6 mod motor showed average gains within 0.2 of each these numbers so consistence this far is good.

Now we get to the 4V test mentioned earlier. When I looked up the results they were somewhat better than I had remembered. The tests were done at Dallas Mustang and were on (if I remember rightly) the dyno operators own near stock 4 V Mustang. These tests were something of an anomaly. On a car that made initially some 260 rear wheel hp and 269 lbs-ft of rear wheel torque the average figures rose by no less than 16.3 lbs-ft and 13.1 hp! That’s a lot so I think it wise to consider possible reasons for this. First we have a 4V engine that, regardless of the port disablement for swirl, still has relatively ineffectual mixture motion. A monstrously aggressive spark could help such a situation here in just the manner we see. Alternatively there may have been an ignition problem that was minor in nature and went unnoticed. The installation of the plasma unit might just have fixed that problem, at least over the rpm range tested, and as a result the figures all look better than would otherwise be the case. At this stage it’s hard to say. But a couple of other tests on 4V engines have shown relatively big increases in the order of an average of about 10 lbs-ft and 9 hp so it looks safe to conclude that real gains are on the cards but just maybe (and only maybe) not quite as much as our Dallas Mustang tests (By the way thanks guys for running those tests).

So does plasma work – sure looks that way and the implications are that it pays off in 4 v motors more so than 3 or 2 V units. What we are not testing for here is mileage. There is little doubt in my mind that the unit will result in better mileage just as a bolt on piece but that isn’t where it’s true strength lies. All the smog equipment used (read cats for that) almost dictates the need for a fuel air ratio of 14-15/1 for the cat to work. This ratio is far to rich for maximum economy. The leaner the ratio used the nearer the engine gets to a diesel cycle. Where the plasma unit could well score big time in the fuel economy division is in terms of lean burn. I have had experience lighting off mixtures as lean as 22/1 and my guess is that given the right circumstances a plasma spark would do even better. Bottom line here is plasma gets my vote and let me tell you - that does not come easy. GFN score 4.9 out of 5!

For more info hit Okada projects site at OKADA PROJECTS | ƒIƒJƒ_ƒvƒ�ƒWƒFƒNƒc | “_‰Îƒ`ƒ…�[ƒjƒ“ƒO | ƒvƒ‰ƒYƒ}ƒVƒŠ�[ƒY

David Vizard

[havok91]

Thanks for doing a write-up on this, I've been wondering about some real world results. A couple of years ago, in Race Car Engineering, I read about a similar system being developed. Being so long ago, and not hearing anything promising since, I thought it had been dropped. However, as always, you uncover the truth.
Looks like this will go on my 4v V6 build.

Mike

[havok91]

Excellent write up. I have always wondered about the effectiveness of this concept on ignition systems. I read a few years ago in Race Car Engineering about some development of plasma ignition systems. I hadn't heard anything promising about this, or anything in a while for that matter, so I thought it didn't pan out. But leave it to you to uncover the truth. Looks like this will go on my 4 valve V6 build.

Thanks again,

Mike

[BLK98MK8LSC]

The 4.6 4v is an engine that likes to see alot of spark. 5.0 mustang/super ford ran a dyno test that showed 7 hp and 4.75 lbs of torque from a spark plug change using brisk LGS plugs. I wonder what the combination of the plasma box and this style of plug would show? Would milling the head for a smaller combustion chamber help this? Or would a roller wave style pop up piston the way to fix the lazy burn characteristics. You wouldnt happen to know what the EGT numbers were when you ran 20to1 air fuel ratio??