Rarely discussed power producing Ignition tech. 

You remind me of my Grandpa, he was a mechanic for 60 years and owned his own shop for 50 of those. He was the most brilliant man I knew and didn't even graduate high-school. He could explain how something worked so anyone could understand it. He was a die hard Ford man and even came up with a couple fixes for common Ford engine problems that I was lucky enough to learn from him. His favorite engine was the 390fe. I miss him, the world lost a lot of hard earned knowledge when he passed.

Adding resistance increases the duration of the discharge. The inductive cable kills the di/dt which is what causes the emi. It also increases duration. Inductors cannot have instantaneous current change. Fast current edges are the main culprit for EMI/RFI I designed a emi supression kit for points ignition that got it so quiet that it was quieter than modern coil on plug. It was used on fire trucks in the state I live in so the wideband receiver / narrow channel could be used on gas powered trucks

As someone that used to work with explosives in the oil patch and seen my share of fuel tanks go up, I can easily say fuel burns and doesn't explode. What most people hear (in reality, not the movies) is the pop of air rushing or combustion escaping. A proper explosion doesn't go boom. It sounds like a jet breaking the speed of sound because that's what is happening. I never filmed those ones, because I was being safe, but I have filmed a few good pops haha.

I remember the Sun Analyzer very well. Even saw one go onto Pawn Stars and nobody cared about it. Using that in about '62 was the first time I had heard of dwell and dwell time. All the other things it could pick out were great too. And it gave you a graphic image just like an oscilloscope would. It was the best. Of course, today's cars are so different. Coil on Plug, computer everything. I had to pull into a parking lot to try and change the radio station this morning. Someone screamed, "Whataya doing, grandpa??" I yelled, "I'm looking for Cousin Brucie on this thing." He screamed, "He's not on now."

Thank you Sir for your tutorials - I have learned so much from your books and now also from your videos . Belated but so sorry for loss of your daughter - one of the hardest things ever for we are not supposed to outlive our children

I've been sitting here watching your shows for hours, all night actually. David I've bought several of your books and built a 427 BBC motor for my 72 C/10. I'm getting ready to take a 4-bolt 350 to the machine shop and go on and get a crank and stroke it. Those 383's are a strong motor! Thank you David for sharing your expertise!

Thank you Mr.Visard. I am looking forward to the next in this series.

This is such a great series, THANK YOU for putting this all together!

My "assumption" of the knock / rattle metal on metal ping sound is relevant to the pressure increase exceeding the ability of oil to lubricate. Metal on metal is like hammer on hammer. Isnt that why it makes the sound it does, because it "is". My two cents (mechanic of 20yrs). Oh by the way love your videos. First one I watched I thought you were going to get taken down by youtube due to releasing well kept secrets. We are all very blessed to have this opportunity. Matt B

WOW I have learnt so much with this, I will have to go back and watch the other and the future vids.

Thanks for all you do!

Thank you truly , for sharing you hard earned knowledge with motor heads .🙏

Just started work on a Triumph triple. Hoping to add a little pep. Love this stuff. Instant sub.

The spark initiates a coronal discharge cloud, which then initiates an electrical cascade in the air and fuel in the range of the corona, and this is where actual flame begins. It starts as a 'candelation point' before there is a flame front propagating.

Thank you David. A bit more technical but that is what I like. Interesting facts about the top ring and its affect on torque/HP.

I've ported heads for 30 yrs a big part off my cylinder head no how came from ur books & videos thank u amigo !!!

Awesome stuff as usual David. Please keep the 4 valve stuff coming as I am very interested in the approach with the single intake port v's samesed port approach and how to induce twirl v's tumble with the siamesed port shape in conjuction with the polyquad modification. Iam modifying jetski heads these days and this is the closest episode to deal with the cylinder head type. I know most of the typical sigle port flowing priciples still apply but am eager to learn more oabout 4 valve types. i look forward to the polyquad episode and please keep up your great work DV you are a legend 😁

Always learn here and I have know creatures that set a number if class and track records. This man is a genius.

He reminds me of my shop proffressor he was a warehouse of hard learned knowledge. He taught me a lot.

Knock is a sonic boom at approx. 750 mph and is an explosion as far as engine is concerned because the shock wave causes high resonance of piston rings which will break the top ring seats, very bad. The maximum burn rate for longevity is just below this. Computer cars can constantly tune the engine for a burn rate just below this; they automatically adjust for different octanes which is their main advantage. Older ignition systems had to be tuned manually to the octane gas being used and they worked well.

Can you discuss your view of plug reading. The carbon ring which few talk or know about. Burn rate on threads and timing on the strap. Steve Morris has a good video. I’d love to see one from you on plug reading

Nice agin here from Denmark this is the ultimative best explain og All time 🙏😉

Thanks o g. We love u for this!

Explaining the DELAY. When the spark plug discharges, because of the extreme turbulence in combustion chamber, the tiny lit portion of the fuel breaks up and becomes a whole bunch of tiny burning spots in the chamber. I once have read that this was called, "Fulguration: emitting flashes of lightning." As these spots grow larger, their surface area becomes much larger and the overall burn rate suddenly increases in speed. This is where the MSD ignitions come in to make a lot more power as they make a whole lot more of these little burning spots at the time of ignition and therefore the delay should be less. Also, I've always thought that the noise that was heard from preignition was the increase of piston slap and hammering of the bearings. I'm not sure if that's true, but it sure makes sense. I sure love your show.

NGK and Sumitomo Love my Whitaker's 😊

It's been awhile since I last touched a distributer. And honestly, I don't miss them.

Thank you for your knowledge. Ive noticed big difference using a msd 6a with the e3 spark plugs. Im not an electrical engineer but wonder if looking into using a ferrite for electrical interference.

Jacobs ignition was some of the best stuff sadly they were absorbed by Accel and that was the end of that .

GM fitted an engine with a quartz lens in a cylinder for viewing and took photos of the two colliding flame fronts. The photos are shown in a book about high performance engine design. A domed piston can also cause the problem as the dome can split the air and keep the flame from traveling across the face of the piston.

I want more spark power, little more power never hurts. Thank you David!

NGK and perhaps Nippon Denso?

Gm had a stock piston used back in the seventy that was dish with the top ring land beveled down to about twenty thousand of a inch from the top ring this piston was found in the police performance engines, boy did they make some power.

Thank you sir 👍 I always make time for your videos great job as always

On my last engine I went about overkill, you could not run a stock rotor with it, a friend borrowed my coil and cap, with a stock rotor, it lasted about a day, about 25-30 miles before melting the rotor, and arcing to the shaft!

The MSD multi spark (3) firings on 8 cylinder engines dropped to 1 after 3000 rpm. I owned a sun scope with 12 cylinder trace and snap on counselor.

Thanks!

Thank you very much Mr. David Vizard. I have learned a lot from you. I have some of your books since 90's. Respect and best Regards, Okki Moeljadi

I call it flame propagation. The speed is determined by the fuel, the piston shape and combustion chamber size. One is able to compare flame propagation speeds by the required timing advance required to satisfy each engine. In-cylinder pressure sensors show pressure peaks at some 8 degrees ATDC.

Multi-Fire are the absolute best insulated plug wire/cable on the market...Period. Unfortunately they are very costly and hard to get as they are hand made. I didn’t believe they could be that much better until I bought a set. Only other Problem is that you can’t get a clip on timing light to work with them lol. In order to set timing I have to put a single MSD wire on.

1970 we bought a Sun analyzer for our dealership. I was 12 years old learning how to build hotrods, dragster and funny Car.

I believe NGK and Denso were the two Japanese wire manufacturers

In Australia in the late 70s Chrysler moved the top ring up to reduce hydrocarbon emissions. It was a way to reduce emissions & increase power with no additional cost for machining. Win Win. They got something for nothing.

David, the RFI issues are initially created (ironically) due to DV/DT, IE a voltage with a fast attack. The inductive leads prevent the current in the leads following that curve and the current climbs more slowly than the voltage. The resistive solution achieves a similar effect since the resistor in association with stray capacitance slows the "attack time". Many years ago I used copper leads but with a much higher value resistor than you did, I used a 4700 ohm resistor. (they are manufactured in values called the E12 series) I wanted about 5000 ohms. Modern spark plugs often have integral resistors for a similar reason. The RFI is related to a Fourier transform, it has a lot of relevance in mechanical parts too. Sorry if this is badly worded, counter intuitively the choice of lead should be able to increase spark duration. Two leads laying parallel to each other will be subject to crosstalk, partially due to distributed capacitance and partly due to magnetic effects. These effects are more severe at high frequencies. Sorry if this is redundant info, as an aside it might be interesting to incorporate a magnet in a sparkplug, you should be able to bend or spin the arc...

I have only driven AC Delco HEI distributors, because they were factory original on the cars I got with them [ Cadillacs ], but they tended to burn out, right at the center electrode a lot. I tended to get rid of them and replace them with Holley ignition towers.

Just pondering the pinging or detonation knock and was considering the possibility that it could be caused by cavitation bubbles in the combustion charge

GM fitted and engine with a quartz lens in a cylinder for viewing and took photos of the two colliding flame fronts. The photos are shown in a book about high performance engine design.

I've always thought the sound accompanying detonation/knock was actually the piston/engine fighting preignition. The rattle being the connecting rod either at the wrist pin or the crank.

Is non resistor plugs worth better spark versus resistor plugs?

I use FORD DURA SPARK SYSTEM AND WORKS GOOD WHEN RECURVED

Tanks.

Do u have any videos covering any performance tips for running dual point distributors with high output coils etc ? Thanks

I enjoy watching David Vizard. I drained the tank the delay time the neighbor hears.

What are your thoughts on progression ignitions distributors? Especially for street racing.

The advantage with spiral wound wires is they shield the spark, which suppresses the interference.

I wonder what DV thinks about chamber softening in regards to detonation. And how would he go about it

I run Taylor 10mm sparkplug wires , Accel plugs , HEI distributor with a 80,000 volt coil on my built 327 On my other 327 it has MSD distributor, muli -spark box ,8mm Accel plug wires , AC Delco R44TS plugs , My other 327 has HEI distributor , HI performance wires ,AC Delco R45 plugs , And all these engines run just fine , all have 11 inch clutch and 4 speed trans and 12 bolt posi rear ends

the difference on those three spark pictures is directly related to difference in amperage (think electric arc welding).

Raising The ring land eliminates carbon build up. Also. Around ring land

Just found your channel and subscribed after an all night binge of watching your videos! In the late 1960's I remember my dad pulling into the gas station in his '65 Buick Electra 225 with the 455ci BB and saying "fill her up with Ethyl". I was too young to know what he was talking about so when I was old enough to start understanding, he explained about leaded gasoline and it's anti-detonation properties. Those were the good old days when gas was .29 cents per gallon and if you filled up you got a free hot wheels car for your child. God I wish I could go back to those good old days, even if I had just known then what I now know and had kept all of the classic cars I have owned over the last 50+ years, I would have been rich and would have kept several rare and highly sought after vehicles.

Thank you for the content. Need better sound quality. Thanks again.

DV The 503 rotax a 2 stroke snowmobile/ultralight engine uses a ring that fills the gap in the upper land. I’m guessing it’s for the very reason you speak of? I also noticed on your chart showing the power gains of a higher land there was a drop in Tq and hp at 3000 and 4500. I’m guessing that’s just the characteristics of the engine and or the tune? If someone is building a low revving street engine for better performance and economy such as a 5.2 magnum would this be advantageous? Thanks.

This way you get the maximum cylinder pressure and maximum efficiency from a gas IC engine. Happy tuning! :)

I love your video's but i am personally more interested in more modern non us engines and i was wondering if you maybe also have information about jdm or german 4 valve heads and how to port these ones?

fuel never detonates. even "low speed pre-ignition" is a misnomer. You still have 70% of the fuel just after TDC and if it autoignites it liberates quite a lot of energy in a few degrees of crank rotation. As of SAE WCX 2019, PhD don't know why it happens, and it's such a rare occurrence (1 in 20k cycles) that it takes a huge amount of data collection to find it, and autoignition tends to break whatever pressure sensors are being used. Oil with a high calcium can cause knock, which can be overcome with good fuel. Darrin Morgin says that lean pockets cause knock, and I agree that the faster the burn rate, the better. That's why 11.8:1 AFR is "safe", because the flame speed peaks there.

I know if the cable's aren't separated, you will never be able to set the timing lol

can i please have a link to the book included in the video? i couldnt read the title

Spark power is the result of secondary coil energy to residence this can be calculated with voltage of secondary coil by the number of wire turns in relation to the primary windings. The best example of residence is think back to when you were a kid running and jumping over small Creek banks when you came to a bank that you were not sure of you stop for a moment and back up and got a running start and release all you had and jumped the creek the same with electrical energy. That what the resistor does with the electrical energy ,the RF is reduction is a good side affect of residence.

On an early hemi you can use 2 plugs if you drill and tap another hole.

One thing that is seldom discussed or even realised is the ability of high tension energy to be delayed due to cylinder pressure and solid core cables more so, would like yo hear your views and experience with this phenomenon of cables acting like a capacitor until cylinder pressure drops or mixture richens to match plug gap without engine misfiring

Autolite Black metal copper core plugs are Great in every make American,German, ECT 🏁

GM HEI has the variable dwell chip inside for best spark quality vs rpm p to the HEI build limit (mech, some elec). Pickup and chip can run rather high rpm yet the total assy with ground wire to block, low (3-10) ohm button, tight rotor-post gap and phased with rpm, and just about any wire is not as good as a coaxial aircraft wire-plug deal with quad GND spark posts gaped oh say 0.040-0.045" for N/A high compression. I do a side-gap for the 0.045". The big hp/compr/boost folks may want a tighter gap, that which i dunno.

Sumitomo made spiral wound plug wires for Honda in the early 80's.

Here in France, I use Pulstar's spark plugs on my old VW Polo converted superethanol. So much low end torque on daily driving. But the most amazing result, is on my 2 stroke motorcycle Suzuki TS 200 R and Maico 500 GME. Better everywhere !!!

@6:09 May have already been mentioned, but the answer here is Denso, or at the time, Nippon Denso.

Hello David I have a question regarding I just got a motorcraft 4180 carb used and was wondering if you know of a book about the rebuild and modification of that carburetor when it comes time for me to go through it thanks

The difference between normal combustion and detonation is the flame speed. When the flame speed is slower than the speed of sound it's "normal" and when it exceeds the speed of sound it's "detonation" or an explosion. When the flame speed is below the speed of sound, the shockwave (pressure wave) is always ahead of the flame front but once faster than the speed of sound, the flame is ahead of the shockwave, which piles up on it's self. No different from a plane going through the sound barrier.

when two flamefronts meet how it works with the quenching of the unburned mixture like in an ( two spark plug per cylinder ) engine ?

Have you read "The Doctor's Guide to Optimizing Your Ignition" by Dr. Christopher Jacobs?

The knock...instantaneous fuel burned at 35 degrees before TDC= KNOCK. The sound is the explosion of fuel and air being compressed as the piston comes to TDC in an over pressure condition almost hydraulic in nature.

I think, I'm going with performance distributors. 😀😎

hello , what do you think of taking out the points and adding a pertronix ignitor into your distributor ?.......

David, what is good way to get in touch, i have a Rolls-Royce Griffon v12, would like to talk with you...

What about the Fox Mustang TFI ignition?

Is there a piston with reinforced piston top and with ring landings further down?

You can piggy back external coils.

Was it a windy day when you did this video?

Detonation, if it could be controlled and the engine could stand it, could improve efficiency by increasing BMEP.

Sealed Power and TRW had head land rings, didn't work out, I think DV picked out the reason ,

The GM HEI distributors tended to burn right through at the center of the rotor. Went to Bills Hays Ignition, to see what his thoughts were back in the late 1970's on this. He showed me on his distributor machine on what happened when running the .070" plus clearance on plug gaps. Using a clear distributor cap and with the lights out. You could see the ion storm inside the cap, and as the rpm climbed, the eight points firing at the plugs became erratic. Once the plug gap was reduced to around .040" - .045" problem solved, and the ion storm was gone. No more (from that point on) did we have problems with the burn through on the rotors when running the closer plug gap on HEI's.

I've had two Asian distributors/coils... one worked very well with enough energy to poke holes in all but the best boots, that iron plugs would need a complete changeout in 10k miles. Very very consistent timing and spark. The second was garbage. The weights were sticky, the stops in the wrong place, and the module just sent a signal whenever wherever... So, at 50%, I decided no more of those.

is it ok to use a platinum spark plug in a 1970 engine with a pertronix ignition ? for street use only no racing

you got to get rid of the distributor... run your engine on the dyno with the lights off...its illuminating ( at peak torque and a bit lean)

Can I ask a serious question? Why aren't you using Coil on Plug??? There must be a good reason.

Sound Barrier is 767 Mph.

Burning: Conflageration vs. Detonation. Burn v. BOOM.

How can I donate $500 to the build of the 318 for St. Jude?

OH !!! I KNOW THIS GUY!!! I READ HIS HEAD PORTING BOOKS !!!

The flame front is only one molecule thick under static combustion, and usually not more than 50 molecules thick under peak turbulent combustion, but up to a hundred meters thick at detonation.

Higher compression needs more voltage to produce the same spark jump.

Sana all racing spark plugs motorcycle.