i agree that a straight HEI would not be an upgrade, but simply a change. but i would say that a DUI is probably an upgrade no matter which version you purchase. they seem to be a very high quality unit in any form.

i've done my homework with the pricing on this one though. a pertronix ignitor 2 module is 102 plus about 10 in shipping. this module fits in a ford duraspark distributor. the ignitor 2 has a differnt spark strategy than the duraspark so it would at least be a change (as opposed to HEI). If my stock distributor is worn, an inexpensive replacement can be had for 40 to 50. hence the 150. this represents the most reasonable approach to changing the ignition system, and would be at least as reliable the distributor, whether old or reman.

the headers, i rounded up to 400 to account for proper gaskets (dead soft, type) and bolts (and locks) which do not typically come in a kit.

I wasnt trying to artificially skew the numbers, they just represnt the approach i would take to such a project.



any thoughts on the multiple spark at low RPM's, anyone?

 

If you go back and read my first AND second response to this thread, you will see that I already said that.


Its pretty obvious that you are hell bent and determined to change your ignition system, meborder. So why don't you go ahead and do it?

 

if i was hell bent to change it i would have already done it without asking for any input.

to be quite honest, ive been enjoying everyone's input, aside from the pissing match, and this post in particular.

you seem hell bent that there is nothing better than a duraspark, and that may well be; however, ive asked about 4 times now to for an explination that has some basis in fact and have gotten none.

specifically, im most interested in adaptive dwell and multiple spark. both features that duraspark does not have. You've made a good point about HEI that i had not considered, i.e. it is the same technology as duraspark only in a different form.

you fail to recognize that a DUI in any form is better than a factory duraspark. If this were true, then DUI would not make disrubitors for a factory duraspark.

the users of aftermarket systems have all said that they got some benefit from such a system, and there may be something to the fact that a good duraspark in proper working order may well have done the same thing. but people make changes for a reason. sometimes because they want to, sometimes because they have to. If im going to save my factory ignition i'll do it on the cheap, but if i'm going to spend 240 bucks on a high quality distruibutor (read: a DUI for duraspark), i'd say that was much more of a waste of money than an aftermarket system that, if nothing else, is different than a duraspark.

you say duraspark does everything i'll ever need.... i'm just asking for some proof, be it quantitative, or qualitative.

nobody in thier right mind is going to update thier duraspark to make sure it is in perfect working order, take it to a dyno, then upgrade to their favorite brand of aftermarket, dyno it again, so they can "prove" there was an increase or not .... i'm not asking for that at all.

some have said "i saw an improvment"

that's more than you have offered.

you say that a reliable aftermarket system cannot be built for 150 bucks. i show you how, and all you have to add is that i'm hell bent to do it and i should just shut up about it...... not very helpfull. If it is a bad plan, please tell me how it will be unreliable, because there may be something i am missing, (like the fact that HEI and Duraspark use the same technology ... i admittedly missed that)

as for the header upgrade ... putting on a cheap set of headers is just an exercise in doing work twice .... as much work as it is to put on a set of headers, i'd rather just spend more and get a good set. replacing a distributor is an hour's work ... if it dont work out, i can just undo it ...

i dunno ... this is going no where.

right now i am absolutly 100% positive that an aftermarket system is either better than duraspark, or it isn't.

 

i forgot to ask you on this one, and you seem to be avoid it alltogether.

MSD only provides multiple sparks below 3000 RPM. Above that point it offers extended dwell.

most racing engines do not spend much time below 3k RPM. so how is it that multiple sparks help a racing engine?

please tell me how multiple sparks below 3000 RPM is a waste of effort!?!
these trucks spend almost 100% of thier service live below 3K ... that's where MSD offers the most, right?

I just can't follow your logic ... please help me understand.

 

Bottom line is, if your Duraspark is working properly on your stock engine, you will never notice any difference by changing the ignition system.

 

Haha all the people that say aftermarket offers no gain have absolutely nothing to back it up other than "its just not better." Every guy with an aftermarket system, however, has said their trucks start better and respond better. Take that advice for what you will...

 

(IDI) inductive discharge ignitions e.g. Duraspark depend on the coil to receive a 12 volt supply from the battery, convert that voltage to 10,000 volts, and then release that voltage each time it is triggered by the distributor, due to this fact, IDI ignitions provide a longer and stronger low rpm spark than CDI ignitions, there is a potential for weak spark at high rpm because the coil does not have enough time to saturate between firing each cylinder, roughly speaking over 5,000 rpm....

(CDI) captive discharge ignitions e.g. MSD draw voltage continually from the battery and store up to 500 volts, the 500 volts is always ready to be sent to the coil where it is then converted to a higher voltage, by its very nature, CDI ignitions produce a shorter duration spark at low rpm than an IDI ignition, this is why these units have been designed to fire multiple sparks within the same cycle, at higher rpms, i.e over 5,000 a CDI ignition is an obvious asset, at lower rpms it's redundant and offers no advantage over an IDI ignition.

 

No one said they weren't better. It depends on the situation. I've been doing this for over forty years and have used every thing thats came out since the first electronic ignition including magneto. The OP's original question was would upgrading from a properly installed and working Duraspark II on his stock engine give him any gain. The answer is still no. He will not notice any gain for money spent in his situation. He asked a simple question and got a simple answer. Spend your money wherever you wish. Unsubscribed.

 

You already have the stock Duraspark ignition, that I assume is working correctly. You want someone to PROVE to you that what you already have is better than the aftermarket ignitions out there, or else you are going to take a gamble and go through the trouble and expense to change it out? Isn't that thinking backwards? It is the responsibility of the aftermarket to prove that *their product* is better, to get someone to spend their hard-earned money to buy it and replace the one already on their vehicle. I haven't seen a test yet that proved any sort of performance improvement on a stock engine. Co425 tried, but all he could come up with is two articles where the D.U.I. outperformed a mechanical points ignition. And that was a no-brainer.

Haha all the people that say aftermarket ignitions offers more performance over the stock Duraspark on a stock or street engine have absolutely nothing to back it up other than getting tricked into thinking that if the distributor is polished with a pretty red cap and a one wire hookup, it must be better than the stock Ford unit. Every guy with a working stock system, however, has been wise to save their money and put it to where these engines really need improvement, like exhaust, heads, and cam. Take that advice for what you will...

Thanks, Montana. Some people just don't wanna hear the truth.

 

Montana: Thank you for the CLEAR and PRECISE description in laypersons terms of exactly what we are talking about here.

Lariat: Its not that some people don't want to hear the truth, its that some people don't understand the difference and others don't want to take the time to bother to explain it to them in a way they can understand.

 

DrainBramage: Meborder, the original poster, has "researched" and tried to convince himself and everyone else in here that an aftermarket ignition is going to do something special for his truck. He seems to know everything about the D.U.I. unit and the Pertronix, and is too eager to hear how "great" they are. While he was busy getting a comprehensive list on pricing aftermarket ignitions, he should have been researching the basic differences himself, instead of being so quick to dismiss the guys in here trying to save him some of his hard-earned money on needlessly changing his ignition.

 

the most informitive post in this entire thread.

thank you!

 

you took the words right out of my mouth .... i'm not quite sure why it has take 5 pages of bickering to get to the heart of my question.

thanks!

 

Okay, all this arguing and lack of real information led me to research cdi vs inductive ignition myself. I did a google search for "capacitive discharge ignition" and found a lot of information on both inductive ignition and capacitive discharge ignitions. Meborder, be sure to read several articles so you don't read just one side of the story. Generally I have found fte to be a great source of information, but this thread has just turned out to be a lot of bickering with very little information. Good luck, Meborder, I'm out.

 

the OP has spent his time trying to pry information from people who proclame to know something about it...

and yes, i research the heck out of everything before i spend my money on it.

my list has been far from comprehensive .. but i did my homework. I do know some of the basic differences, but was eager to learn more. instead ive got some people telling me they are right and provide very little to support their claim.

to be honest ... you've been kind of a jerk this whole thread, in particular to me .... and all because of your own inability to express you knowedge in a clear concise manner as others have done, and my unwillingness to accept your position "just because you say so".

you asked the exact same question a while back on this thread, and in about four responses you became an expert and duraspark and its advantages over any other system ever created. And, perhaps you are an expert on duraspark, but your ability to express facts in a clear concise manner leave something to be desired.

thank you for your input.