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david123 wrote:I cannot see how offering thoughts on one type of seat, or tyres, or ignition systems differ.
Awesome, as a fellow scientist I don't need to explain the critical difference between quantitative and qualitiative data. Tyre choice is an intensly personal choice but things like cooling abilty of ali vs copper radiatiors or power increases from ignition systems could be measured if you wanted to and therein lies the critical difference.
If the universe ever conspires to put your zook and a dyno in close proximity i'd love to see even just a single pass and a list of engine mods that could at least be compared to factory output.
Did the MSD system include a plug and lead upgrade?
David 123, unfortunately, you've blundered into one of the pet hates of some of us - the "amazing" fix. I asked whether you have tried anything else ignition related for good reason. I've had similar "amazing" results purely by changing plug leads from original 15 year old leads to new 8mm stuff. Yes, there was an "amazing" increase in off idle/low rev drivability where ignition improvements on otherwise stock engines will bear the most fruit.
For an engine with a stock cam and had design and stock compression, I'd reckon the stock spark energy (with the system in good condition) would be more than adequate, but lead break down will loose a lot of that energy.
As an ex scientist, I'm sure you understand well the importance of proving and backing up claims. Many people on here will spend money based on what the "experts" on here say. There are many many more lurkers on here than members.
I only had a dig about fuel line magnets as the kind of information you posted is EXACTLY the same kind of claim they make for their product - with little or no data to substantiate the claims.
As for claims of substantial improvements in HP/economy with high power ingnition in otherwise stock engines? Much of the data on these seems to hinge on old engines. I don't think I've ever seen data on a new, stock engine gaining substantially with an ignition upgrade, which tends to make me suspicious it's less about the shiny box and more about some TLC on the ignition system.
I do understand that worn, high compression, highly boosted, or heavily cammed engines might benefit from more ignition power, much like the rail information MM posted. (55A magnetos - gosh!)
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
Till very recently I have left ignition unattended to, but, its pretty easy.
Please forgive me if I'm too basic.
Inside the chamber is a air fuel mix, less its correct it will not burn, 10-12% or so, and unless its desiel, its needs a form of ignition.
If the ignition, spark, is weak, then as the time spent between ignition then combustion and power is short, the fuel will burn slow, and so, a lot of the fuel will exit the combustion chamber unburnt. resultant action, exsesive fuel consumption, and lack of power.
Now add a big fat bright spark, ignition happens far faster, and so, less fuel is exited out the exhaust, and is turned to power as more is actually burnt.
Take this a step further, and a few dirty great big fat sparks, one after the other from a hot shot ignition system, result, far far less fuel is unburnt, so, the fuel, inside the combustion chamber, is burning, as it is designed to, completely, and so, is forcing the piston down, better and with much more force, result, less fuel consumption for the same power output.
There is a lot of science behind this, you can go into megajules, voltage, amperage etc, but basically, the bigger/hotter/longer the spark, the faster the petrol ignites, and the more is burnt with less going out the exhaust.
Remember you are talking miliseconds of duration where the spark has time to ignite the air/fuel mix, understandably, the more spark, the more complete the burn, and the more complete the burn, the more power is generated.
Hope this made sense.
I have played with engines alot, and as a 4wder of er, pertty stupid conviction, I have to say, you can place tyres etc against one another.
Try a hill, same machine, and do a tyre swap, one will make it, the other is left wanting, mud, one clears the mud from the tread, the other blocks up etc etc etc.
ok the radiator anology wasn't there, as its easy to explain why aluminium is far superior.
My zook motor is unopened, but has extractors, so it scavengers the combustion chamber better, I have a much bigger carby, so it adds fuel at a greater rate than the ignition system was designed to handle, so I added 4 pin plugs and 10mm leads and a better coil, a GT40.
This resulted (unscientificly) in better combustion, and so me lil toy went better, again, no way to prove it, but as my lil toy is pretty much unbeatable, the results speak for themselves.
Now add a far far brighter, hotter and longer duration spark, the fuel ignites far better, faster and more complete, result, more broom. MSD.
I would love to take her back to when I first got her, and she was stalling in low first, to now, with bigger fatter tyres that I can spin easily, in high range, must have some power improvement.
Bung her on a dyno.
Would I, naaa, means going back to stock everything, then changing again, id just go by factory claims, and the compare it to now.
I cannot envisage me driving 1,400k just to put her on a dyno, thats there n back, mind, Id love to, if I can get this increase in power, imagine what a tuning master could get, differnet plugs, bigger gaps, change the dizzy springs to alter the advance, man, that would be nice.
My next job is to get a better seat, I have looked at lots, some look wonderful, but are a big job, some are easy but are not so good. may just get an automotive trimmer to measure me and work his magic on my stock seat.
As to the magnets, I am in no way affiliated with MSD, I only speak from my feelings, how me lil zook perform, not from science.
High performance ignitions improve engine performance by ensuring ALL fuel is burnt.
MSD stands for Multiple Spark Discharge and differs from a standard ignition system in that instead of one spark (of mediocre quality) being delivered prior to the power stroke of each cylinder you get multiple sparks that will blow a hole in your hand if you are silly enough to hold the lead!
Oh here .. MSD can explain it better than I can. http://www.msdignition.com/pdf/tech%20b ... top_10.pdf
want33s wrote:High performance ignitions improve engine performance by ensuring ALL fuel is burnt.
MSD stands for Multiple Spark Discharge and differs from a standard ignition system in that instead of one spark (of mediocre quality) being delivered prior to the power stroke of each cylinder you get multiple sparks that will blow a hole in your hand if you are silly enough to hold the lead!
Oh here .. MSD can explain it better than I can. http://www.msdignition.com/pdf/tech%20b ... top_10.pdf
HAHA they're a great way to wake up. Just try to pull the coil lead off with engine running.
Bosch don't recommend a replacement coil for a sierra. The operation and weaknesses of the sierra ignition module has been covered before on here though.
Between the 10mm leads, 4 point plugs (are they 300% better than one point plugs?) and mismatched coil to ignition system, I'm unsurprised the MSD performed better. There's no telling how the spark actually behaved in the cylinder but it's a fair bet the stock igntition module was a long way out of it's operating parameters. You have a mismatched motor setup and haven't changed the ability of the engine to flow air at all - cam/valves/compression, but have done all the sh!t and glitter around it. Yes, I'm sure you have "under the curve" gains, but they will be small- our original point.
You seem really good a reading the information on the side of the box (or the internet) though on the sutff you buy
Oh, on a side note, The rate at which a fuel burns is unaffected by how bright the spark is. Once the mixture is in the combustible range, burn duration is an effect of fuel type (crudely octane) and has nothing to do with the spark. I can ignite a volume of air/fuel any way I like, the energy released in the explosion is set by fuel, not the means of ignition.
Another spark event might light off a whole lot of unburnt fuel if your car is running rich though.....
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
Gwagensteve wrote:
Oh, on a side note, The rate at which a fuel burns is unaffected by how bright the spark is. Once the mixture is in the combustible range, burn duration is an effect of fuel type (crudely octane) and has nothing to do with the spark. I can ignite a volume of air/fuel any way I like, the energy released in the explosion is set by fuel, not the means of ignition.
I thought i remember reading something about spark temp, duration and geometry all affect how the combustion propagates inside the chamber thus affecting completnes of burn and the amount of energy liberated?
"You seem really good a reading the information on the side of the box (or the internet) though on the sutff you buy"
Been playing with upgrades since my first car, a 72 hq ute in 73, my knowledge is not from weeties packets.
pretty insulting.
Even a complete idiot knows of vast gains over stock closter exhaust manifolds and small choked up cheap systems by extractors and a free flowing system, not to mention intakes.
"Oh, on a side note, The rate at which a fuel burns is unaffected by how bright the spark is. Once the mixture is in the combustible range, burn duration is an effect of fuel type (crudely octane) and has nothing to do with the spark. I can ignite a volume of air/fuel any way I like, the energy released in the explosion is set by fuel, not the means of ignition."
Sometimes it is better to keep ones mouth shut and be thought of as a fool, than to open your mouth and prove it beyond any shadow of a doubt.
*Disclaimer 1* I'm not having a go at anyone, only looking at the data linked
*Disclaimer2* I'm not doubting that high energy/multiple event systems have a place and can add power where the spark is getting quenched by high cylinder pressures etc (or old, degraded ignition performance). I'm also not doubting that MSD type systems can improve off idle and low rev drivability due mostly to poor low rev cylinder filling on carby cars and poor mixture control. I do think the claim that build power in other wise stock engines with good condition ignition systems is dodgy.
to the link:
4HP gain with oil and MSD? That's 2.25% - well below dyno tolerance for runs at different times of the day - I think that difference would be acceptable even between consecutive runs - but the recent thread on oil tech shows that this level of power increase could be attributed to a change in engine oil alone, let alone engine, transmission and diff oil.
Also, this adds weight to my original comment that a new car wouldn't show that improvement with an MSD on a stock motor. This mustang was 18 years old! How good was its leads? I've felt off idle drivability improve with only a lead change on a 10 year old engine...
Interestingly, the power and torque graphs are almost identical... not leading any weight to the claim of improved bottom end/midrange with MSD systems.
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
david123 wrote:
If the ignition, spark, is weak, then as the time spent between ignition then combustion and power is short, the fuel will burn slow, and so, a lot of the fuel will exit the combustion chamber unburnt. resultant action, exsesive fuel consumption, and lack of power.
Now add a big fat bright spark, ignition happens far faster, and so, less fuel is exited out the exhaust, and is turned to power as more is actually burnt.
If stoichiometry is close to ideal within the chamber any type of spark (ie ignition) will cause complete burn correct?
It seems the argument against a 'weak' spark and a 'strong' spark here seems to do with the actual time the spark ignites the compressed air/fuel mixture. Hence it seems that we are focusing on an effect of ignition timing. Maybe this MSD system is advancing the spark someway or another? What was the timing set to before and after the installation? Just a query?
My cent worth.
David123 ran a gt40 coil - a Bosch item. Bosch don't recommend this coil for a sierra.
My comments about David123's use of big fat leads, big fat plugs, big fat coil, stock ignition module is why I commented on the "weakness" of stock sierra ignition modules - they're not designed to control greater than stock spark energy or resistance.
"You" was in reference to David 123's almost perfect rewriting of all the advertising copy for the advantages of high energy ignition. It just reads like propganda.
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
"You" was in reference to David 123's almost perfect rewriting of all the advertising copy for the advantages of high energy ignition. It just reads like propganda.
Steve.[/quote]
goodo.
In one breath your saying that what I have dun is wrong, and that it can make no difference, next breath your saying that yes, zooks have a poor ignition system, then you say any spark is the same as another, crikey.
david123 wrote:"You seem really good a reading the information on the side of the box (or the internet) though on the sutff you buy"
Been playing with upgrades since my first car, a 72 hq ute in 73, my knowledge is not from weeties packets.
pretty insulting.
Well, you're doing a pretty good job of trying to insult us "wannabes" with some junk you read off a website. do some research about ignition systems and you might recognise where you slipped up with your previous setup thats making your MSD look soooo good.
david123 wrote:
Even a complete idiot knows of vast gains over stock closter exhaust manifolds and small choked up cheap systems by extractors and a free flowing system, not to mention intakes.
That'd take a dyno though, wouldn't it? Many sierra owners have had questionable "seat of the pants" improvements with extractors and free flowing exhausts. (but a great increase in power adding noise) There's plenty of info on this around too, although some of it is written by the wannabees on here though, so it's rubbish.
gwagensteve wrote:
"Oh, on a side note, The rate at which a fuel burns is unaffected by how bright the spark is. Once the mixture is in the combustible range, burn duration is an effect of fuel type (crudely octane) and has nothing to do with the spark. I can ignite a volume of air/fuel any way I like, the energy released in the explosion is set by fuel, not the means of ignition."
Nope, still can't see the problem with this. If it's going to light, it's going to light... and it will burn at the set rate for that fuel and mixture. It's only going to need "more" spark if it's borderline for the combustible range - i.e too rich, timing out etc. which should all be outside of stock parameters. (which your car is not - it's a collection of different mods, all unproven as a whole)
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
david123 wrote:
In one breath your saying that what I have dun is wrong, and that it can make no difference, next breath your saying that yes, zooks have a poor ignition system, then you say any spark is the same as another, crikey.
Sierra ignition systems are perfectly able to support good combustion in a stock motor with good condition components. (Or amongst other things, they wouldn't have passed emissions) but at 15+ years of age, who knows. If you go mismatch the whole system the ignition module will become the weak link.
A spark will ignite a stoichiometric mixture. It doesn't take a special type of spark from a special type of red box to do it. The energy of a stock sierra system is perfectly adequate for a stock engine. tHe issue comes when resistance goes up the in the chamber, whoch can be caused by mixture (including oil) or cylinder pressure, which is why high boost/high compression cars need more spark. But put a new sierra on a dyno and a new sierra with an MSD box and I'm quite sure the dyno couldn't pick it, which is why these dyno comparisons ALWAYS start with an old,stock or boosted test car.
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
Im sorry Steve, of course your right, I will take off all my mismatched mods, and go back to the stock set up that used to stall in first gear low range, because obviously I have wasted my money on all this hi falutin bogus gear, go the bog stock standard.
They don't inherently stall in low 1st stock, yours will have had had a problem that through all the stuff you have tried you've cured.
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
In the case of her stalling, I was refering to trying to climb at near end for end angles.
And the point of my initial post was just as you stated, thru all my buggerisin round, I've cured and improved my zooks engine power, and to tell of what I did, in the order, and the difference.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
Alright from what i've read I tend to agree with Steve in that ye you may have felt some substantial gains but this i most likely due to an existing fault with the ignition system (worn parts etc).
Now in my experience with CDI ignition systems they don't give you brilliant power gains if your ignition system is already in good nic for the application. If you run a good condition factory ignition setup then put 20psi of boost into and engine then this is one kind of exception to that.
I run a Crane HI6 capacitive discharge ignition module, eagle 11.5mm spiral core leads, Splitfire plugs with about .4mm extra gap and a Crane PS92 coil in my V8 commodore. Now you have to understand a few things about this car first. It had alot of modifications before the crane setup was installed (upped compression, massive cam, worked heads, big zorst, twin throttle intake, bigger injectors and custom tune etc etc) so I thought I'd lash out some money on ignition thinking it was warranted.
Now I'm not saying it was a waste of money but it's definately not a good "bang for your buck" modification. The only difference I could feel was ater about 5000rpm it seems to rev smoother all the way to redline (about 7000rpm) and also the rev limiter was alot ncer than the factory one (makes letting your mates drive with 2000rpm limit fun ).
JrZook wrote:
If stoichiometry is close to ideal within the chamber any type of spark (ie ignition) will cause complete burn correct?
This is basically my understanding, however the spark must be powerful enough (enough voltage). If the air-fuel mixture is stoichiometric then you will require 'x' amount of spark energy to ignite. any more than this will be useless, as at the stoichiometric ratio if all the fuel burns so will all the air etc. Therefore you re-tune your engine to run rich, you will still have unburnt fuel even if you whack out 9,000,000,000,000 volts through your spark; because there is not enough air to burn with it.
Now as for how gains could be achieved. This is my only possible reasoning as to how gains could be made: Standard Sierra runs rather lean (very likely), if you just purely run the engine richer (closer to stoichiometry) the standard spark ignition system will not be able to ignite all the mixture as it does not supply enough energy (plausible?). By adding an uber-ignition system you provide enough spark energy to ignite this richer mixture, and hence this is you extra energy. Therefore the ignition upgrade requires re-carburation to be truly effective (which David did state he had done).
Please feel free to comment on my idea, I still would like a better understanding, its seems.
OK I just looked up the Aahenius reaction rate equation for pre-mixed flame spark ignition, the equation indicates that the "Time to ignition" (ie delay time from spark) is related to purely properties of the combustion environment and fuel/air mixture. There is no relation to spark energy.
Tig = (rho*C*T)/((m-1)*dh*w)
rho = density
C = concentration
T = temperature
m = (can't remember its name, but T dependent)
dh = energy/mole
w = reaction rate = K*Ca^n*T^m
Remember this is assuming the reaction is adiabatic so it is not a "perfect" solution, but good enough (especially for this discussion).
So I guess my current understanding would be that upgrading ignition alone will do SFA, however doing it in tandem with other engine modification could bare fruit.
Anyone?
Wheeling on completely wicked angles, without even looking stable.
That's a much more elegant and thorough explanation than I was able to produce, but I think we're on the same page.
Personally, I think a sierra in stock, new condition has perfectly adequate spark power, but as the car ages spark power is reduced, principally through lead degredation, but there will be lots of other areas where loss can occur.
After all, poor spark performance will have a big effect on emissions.
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
My understanding of this is that we have no need for any form of decent spark, because a spark is a spark, if its weak or extreemly hot, it will do exactly the same thing, as its the fuel that does the job, hmmm.
Ok so that was a bit over the top, but from my understanding of things, being informed about the whys and hows of spark by an electrical tecky is that it is very different.
A car is made to extreemly tight budgets, and so the carb is adequate, the exhaust is adequate, as is the ignition, well, good enuf for the adequate system it looks after, now up everything.
Lets say that your average engine brand new, produces 70% of its capable power, this is from the manufacture not using the very best possible.
Now up the anti some, add a good exhaust, a bigger better carby, so she gets rid of the crap far better, and drinks the juice far faster, and in theory we have upped the power to a possible 90% of the unopened new power, but, we have a stock ignition system, trying to handle 20% more power than it was designed for.
Power gains, yes you have upped the power, but not by much because the whole thing is held back by a less than adequate ignition system.
Now add a hot spark, one that is more than capable, instant uptake in power.
How many out there run fully stock, no changes in exhaust, even just a bigger pipe, or extractors, run 98 instead of crap fuel, use a good quality Kn N air filter, have added an after market bigger better carby, are you gaining the full power % upgrade, unless you have upped the ignition, sadly, no.
Sorry if it seems that I have read this on the side of a weeties packet, but its my knowledge of things.
Anyone who looks after their car replaces leads and plugs regulary, as with their cap, my plugs, leads n cap get biffo at about 20,000k, probably should be sooner, but there ya go.
'93 sierra WT, 2" BL, 3" TG springs, 2" zorst, CD, 235's
To do: xtractrs, bigger tyres, gears, etc
See members for pics/info
http://www.outerlimits4x4.com/sutra1368130.php#1368130
Probably a bit too far in the past for most - but does anyone know WHY MSD has multiple sparks - its to FIX a problem with CDI's, not a feature...
CDI's generate a HV pulse with a VERY rapid rise time, this is useful as it can overcome plug "charge bleed off" with slower rise times associated with inductive systems. Two strokes often use CDI systems as the oil creates deposits on the plugs, rotaries also love CDI's for slightly different reasons, the short rise time can assist in overcoming there special issues.
Whilst a short intense spark sound great - it can lead to ignition / insulation issues if not well designed and maintained.
With many engines ( particularly American V8's ) the short spark duration from a CDI is a significant problem. Due to issues of mixture distribution around the plug electrodes, poor combustion chamber design etc etc a short spark can cause intermittent combustion problems.
Even changes to plug electrode geometry can cause issues ( so swap plug designs carefully ).
MSD came up with the idea of selling "multiple sparks" to try and overcome this problem ( generally successfully ) and have used it ever since. Resonance always exists between the discharge capacitor / coil so it wasn't a big step to allow it to produce a second ( or more ) sparks but it did solve the duration problem.
Inductive systems don't suffer from the short spark syndrome - they produce a long discharge by their basic principle of operation and hence don't need multiple sparks as a single long one is effective.
Inductive systems have improved significantly in the last few years, coil design is much more efficient and the electronics in modules has become very intelligent - generating substantially more energy then was previously possible and with long sparks. COP systems have also moved inductive ignition into another league.
And a GT40 coil on a zook module - mismatched......
( usual disclaimers )
It seemed like a much better idea when I started it than it does now.
Id try n explain it, but id sound like I was just rewriting from a web site or a box, my brother is the one, but he uses very tecky terms that has my head spinning, electricity is not my field, its there it duz, give me the simple explination.
Why is a GT40 missmatched, it has made quite a diff and when I rang MSD and asked whether to get a Master Blaster coil, was told, no a GT40 is good.
david123 wrote:Why is a GT40 missmatched, it has made quite a diff and when I rang MSD and asked whether to get a Master Blaster coil, was told, no a GT40 is good.
Thats a good question David, with an inductive system ( stock Suzuki ) the energy required to produce a spark is stored in the magnetic field created by the current flow in the coil.
The ignition modules role is to manage and switch the current flow ( dwell basically ) to ensure that the current has achieved the desired energy storage and no more ( otherwise you get a poor spark, overheat or destroy things ).
On modules the vintage of the zook the dwell is basically fixed and designed to work as well as possible with the electrical configuration of the coil it is designed for. Change the coil and you have disturbed the "match" between module and coil. To get higher energy out of a coil you need to put more in and the module may not be capable of this - or be damaged if it relies on the coil to current limit, which on early modules isn't uncommon.
CDI's however store their energy in discharge capacitors, which are "dumped" into the ignition coil when a spark is required. In this case the coil doesn't store any energy - it simply works as a imperfect pulse transformer, so many of the design characteristics that matter so much with an inductive system aren't a problem.
However a coil designed for inductive discharge isn't ideal, a true CDI coil is a pure pulse transformer and will produce substantial output gains from CDI systems. Mercruiser outboard CDI coils are very popular. A pulse coil can't be used on an inductive system.
Word of warning here - the switching components of some aftermarket CDI's are not capable of switching pulse transformer coils and can fail so some care is required if the manufacturer doesn't make a recommendation.
( usual disclaimers )
It seemed like a much better idea when I started it than it does now.
).
