High Energy Ignition (HEI)

[Farrar]

Volvo and Renault were both partners in the Douvrin plant (along with Peugeot of course)....

I give up. Even if I'm right, I'm wrong.

Farrar

[content22207]

Dunno who is right or wrong, but I do know now that Renault was hemorrhaging money throughout the 1980's (just learned that looking up info for another thread).

I always assumed that since Renault was able to buy a controlling interest in AMC and build a new factory in Canada, they were profitable. Apparently nothing could be further from the truth. Renault lost money every year between 1980 and 1986, racking up a staggering $5.75 billion in losses (more than $11 billion in 2010 dollars). New management was able to turn a profit in 1987 and 1988, in no small part by selling Renault's share of AMC to Chrysler, but by the end of the decade things had turned sour again (profits plunged 87% in 1989 alone).

Must be nice to be a government owned auto manufacturer. Thank God that could never happen in the United States. Oh wait, nevermind....

Bill Robertson
#5939

[DCUK Martin]

2. Deloreans suck and Martin likes it.

Grow up. If there's a genuine need to reengineer something I'm there with bells on, but I'm a firm believer in "if it ain't broke, don't fix it"... with the additional caveat of don't go crowing from the rooftops using as flowery language as possible on "how badly engineered and sub-standard these silly little cars are!". Stick to the facts, wherever possible stickin gto solid engineering principles along the way....

Bosch ignition is not optimized -- it is minimized.

No one outside of a narrow segment of the narrow European market ever used it. Bosch ignition was adequate in Europe because:
- Their compression ratios were higher
- Their fuel mixtures were richer
In the North American market, it is barely functional at best, with absolutely no wiggle room for variation or degredation. That is one reason why a DeLorean engine can run acceptably one day, then suddenly run very badly the next.

What a complete and utter howler of a post!

1) Have you ever actually TRIED opening up the plug gaps on a stock coil? Given I *know* it'll maintain a spark under twice the pressure generated in a stock DeLorean engine, I'll cheerfully put money on it working just fine. Remember: I use it on my turbo engines under 15psi of boost producing well over 200hp. "Barely functional at best"?!?!?! Get a life...

2) You've got your facts completely backwards - it takes MORE energy to generate a spark when under more pressure, not less. I've repeated this fact a hundred times but you're still ignoring it.... can't think why.

3) Running a carburetor gives you much less control over the mixture and no engine likes to run lean, yet all will run pretty much fine when rich (not talking catalysts here!). The more you start to worry about emissions, the closer to stochiometry the engines are required to run. Stochiometry is where the spark plug has the easiest time.

How many times and how large do I have to write the word?
Increasing the gap WILL[/SIZE] increase the voltage at the plug. It's a fact despite what Bill says. It's physics.

Here's what Ron is trying to explain…..

The spark plug will fire at whatever voltage is sufficient to bridge the gap.

If you have a coil that can produce up to 1.21 jigga-volts, but the air/mixture/etc breaks down at 25 volts, guess how much voltage is going across that gap? 25V.

Now, let's say you double that gap. If we wave our hands and summon magic (seriously, I don't feel like looking up the equations right now), we'll see that the voltage at which the spark occurs (breakdown of atmosphere) increases, because of the larger gap.

Simply increasing the gap WILL increase the voltage at the plug. If that voltage exceeds what your coil is capable of creating, no spark will happen.

The key to all this is just WHEN that breakdown occurs. Just putting in a higher voltage coil and a wider gap will not necessarily improve things without other changes.

The timing would probably need to be altered at best. Those modern engines running larger plug gaps also likely have much more intelligent electronics to fire things at just the right time.

...

Debate technique: If you are found to be wrong on one point, quickly throw something else out there to distract the person you're debating with and keep moving constantly.

--buddy

Where's the "What he said" smiley gone....?

Bullshit.
I have it from more than one reliable source that widening it at all will not allow the spark to jump, because there will be no increase in voltage, which is required to make the longer jump.

Umm.... not sure what you meant there, Ron.

Yes indeed, with compression ratios almost three times as high.

Which releases more energy: a spring compressed to 1/8 its original length, or a spring compressed to 1/20 its original length?

To be brutally honest Ron, if you don;t understand the difference between gasoline combustion and diesel combustion, you have no business commenting in this thread in the first place.

Oh my gaaaawd. Did you really just write that? Your analogy of a spring is fundamentally flawed: You have to put the energy in to compress it in the first place, right? And as no energy transfer is 100% efficient, ipso facto more energy is lost compressing the gases in a diesel than in a petrol engine.

The efficiency of any heat engine is fundamentally linked to its compression ratio, but not for the reason you state.

Back to the thread at hand:

If an owner wants:
- decreased emissions
- more reliable combustion
- more complete combustion
especially in a lean burning engine like the a DeLorean PRV, there is no better way to accomplish that than to increase secondary ignition voltage and spark plug gap.

Engineers from AC Delco, Lucas, Ford, and Champion all agree.

That reads like one of those spam emails that says "As seen on TV and even Oprah!"

They don't "agree" with you Bill. I'd love to get a good running stock DeLorean on a gas analyser and dyno and let you do your best with the ignition to see if we get any improvements at all.... but that ain't gonna happen, so we'll just keep fighting on here...

I don't think there has been a new car model with inductive ignition since the mid 1980's.

You WHAT?! Complete and utter nonsense.... ask yourself why even modern cars use "coil packs" !?! Capacitive ignition was used for a brief period to overcome problem associated with coil charge times. Even a quick glance at Wikipedia tells me that:

"Capacitor discharge ignition (CDI) or thyristor ignition is a type of automotive electronic ignition system which is widely used in outboard motors, motorcycles, lawn mowers, chainsaws, small engines, turbine-powered aircraft, and some cars."

Well done demonstrating another yawning chasm in your knowledge.

About 6 months ago I decided to upgrade my ignition. I purchased a high performance coil, MSD spark plug wires, and new spark plugs.

...then did a bunch of othe rstuff to make it run right but you never said how it ran before you decided to "upgrade"?

I'm pretty sure Ron and Martin realize they are wrong, and rather than taking their lumps they are just trying to steer this thread off in tangential directions.

regarding Volvo and Delorean, the castings numbers of heads and cams are in fact the one used from Volvo, so maybe that's why Volvo requested a royalty.

Funny then that the numbers cast into DeLorean parts like the intake manifold, sump and more are actually Renault part numbers.... even the camshaft numbers Bill has posted in his Volvo literature are traceable Renault numbers....!

Must be nice to be a government owned auto manufacturer. Thank God that could never happen in the United States. Oh wait, nevermind....

Yeah, check out Renault's performance today....

[stevedmc]

...then did a bunch of othe rstuff to make it run right but you never said how it ran before you decided to "upgrade"?

YEAH, I believe my statement saying, "Deloreans suck" is enough to explain why I upgraded. 16510 still sucks but its not as bad as before and I have slightly better gas mileage as a result of making it less sucky.

[sean]

Grow up.....

Now that's how to mutli-quote! Thanks Martin!

YEAH, I believe my statement saying, "Deloreans suck" is enough to explain why I upgraded. 16510 still sucks but its not as bad as before and I have slightly better gas mileage as a result of making it less sucky.

HA! Carbs....Reducing the level of DeLorean suck since 2000.

[content22207]

2) You've got your facts completely backwards - it takes MORE energy to generate a spark when under more pressure, not less. I've repeated this fact a hundred times but you're still ignoring it.... can't think why.

Because real engineers, who build ignition systems for a living, disagree with you?

For example, Pages 61 and 62 of the afore mentioned SAE paper (Lucas' commentary):
"The effects of spark duration, air-fuel ratio (A/F), compression ratio and ignition advance were observed.... [11:1 compression ratio results] For these conditions a 2 millisecond spark was adequate until the A/F exceeded 16:1, whereas for a 7:1 compression ratio 2000 milliseconds were necessary for this A/F.... The effect is aggravated by low compression ratio."

Page 64 [Delco engineers' response]:
"... Similarly, with higher compression ratios, the mixture temperatures and pressures at the time of ignition are increased. These conditions reduce the spark duration required to prevent any engine misfires for the same A/F."

This particular exchange involved the study's spark duration tests, but the effects of higher compression also apply to spark energy, gap projection, and electrode size: any given fuel/air mixture is easier to ignite under higher compression than the exact same mixture is under lower compression.

Bill Robertson
#5939

[nullset]

This particular exchange involved the study's spark duration tests, but the effects of higher compression also apply to spark energy, gap projection, and electrode size: any given fuel/air mixture is easier to ignite under higher compression than the exact same mixture is under lower compression.

Bill Robertson
#5939

Easier to ignite has nothing to do with the voltage required to break down the air gap of the spark plug.

The plug will spark at whatever voltage is sufficient to bridge the gap, no matter what the 'maximum output' voltage of your coil is, no matter what your compression ratio is, and no matter what your A/F is.

[sean]

HA! Carbs....Reducing the level of DeLorean suck since 2000.

For prosperity sake, Steve stole it from me but Im ok with that ;-)

[content22207]

Easier to ignite has nothing to do with the voltage required to break down the air gap of the spark plug.

The plug will spark at whatever voltage is sufficient to bridge the gap, no matter what the 'maximum output' voltage of your coil is, no matter what your compression ratio is, and no matter what your A/F is.

Easier to ignite has everything to do with how wide you set the gap. If you set the gap too narrow on a low compression engine (harder to ignite), you risk misfiring not only because the spark voltage will be too low, but because the flame front will be too small.

It's no historical coincidence that American manufacturers widened their plug gaps at the same time they were dropping compression ratios.

Bill Robertson
#5939

[Ron]

Bullshit.
I have it from more than one reliable source that widening it at all will not allow the spark to jump, because there will be no increase in voltage, which is required to make the longer jump.

Umm.... not sure what you meant there, Ron.

[Man, you're really going to make me work here....]

I was being sarcastic (Bill & Steve)....well, sardonic:

Well, It went like this:

I will say increasing secondary voltage OR widening the plug gap will increase energy at the plug gap.

Wrong.Widening the plug gap without increasing voltage will turn your ignition to sh!t.
...
Edit to clarify my response: How the hell do you think spark is going to jump across a wider spark plug gap if you don't increase voltage

The same way it jumps across when some dumbass don't change his plugs out and there is hardly enough material left to recognize that it was an electrode.

It won't.
Voltage must increase until it reaches a level sufficient to ionize the air between the electrodes. If that level is never reached, electrical current in one electrode will never flow to the other one. That is why spark plugs need a transformer (coil) in the first place, otherwise you could simply run your car with the distributor connected directly to the alternator.
Bill Robertson

...you should be guessing that since stock engines run with worn plugs and wide gaps, spark must be jumping across the worn/wider gaps.
So I ask you, "How the hell do you think spark is going to jump across a wider spark plug gap if you don't increase voltage?"

It won't. Put a timing light on the plug -- it won't be firing.
Bill Robertson

[Well, that wasn't so bad...all of the cut and paste reminded me of working for Equifax...at least it wasn't Assembler.]

========

Well, since I'm already here, again:

RE:

No, you did that, as far as I am concerned, when you said t...That invoked the performance/HP-emission crap you kept ignoring from most everyone.
But I see below you are trying to sneak it in now -- Along with your conclusions on their conclusions.
I wonder how long it will take you to pick on a another typo, verbiage, insignificant piece, etc, and start of on another tangent or explode with more extraneous truths.

( It didn't take long, the very next post in the thread: )

Not to point out the obvious, but I *DID* mention emissions (and fuel economy) in the very first post of this thread, as a quote from an even earlier post of mine in other thread....
Bill Robertson

Yeah, you *DID* mention it, but saying, ...

In a low compression engine, like the stock DeLorean PRV, the mixture is harder to ignite. Leaning the mixture out for fuel economy and emissions exacerbates the situation.

...does not remotely address '"performance" including HP & Emissions', whether you did when you said a hotter coil alone would increase it, or your emissions (to name but a few).
Just another extraneous truth.
And, yeah it was where you quoted from an even earlier thread, YOURSELF!
You *ARE* getting sneaky! I'll have to try that one...

=====

Now that's how to mutli-quote! Thanks Martin!

I was proud of this post until now.