TWIN SPARK - WHY, HOW and why it isn't more widespread

[@Born_Stellar]

I remember during my flying lessons we would turn off one magneto (airplane ignition coil) and you'd lose about 200 rpm.

[@bicylindrico]

Same with the Mercedes twin spark engines. You can shut off a single circuit to use for diagnostics and see an RPM change even when switching between the two

[@fchanMSI]

Aircraft with piston engines have 2 spark plugs per cylinder is also for reliably not only power.

[@FSXgta]

@@fchanMSI redundancy

[@SVSky]

Yep, checking for lead fouling on the plugs too.

[@gabrielgavilan5131]

Magneto are quite a bit different than automotive ignition coils, its a very old technology with the main advantage of being completely independent from the aircrafts electric system.

[@mikipelotas3488]

I'm pretty sure Mercedes Benz has a lot of dual spark plug engines too. Great work,keep it coming!!

[@Rourkeize]

Yes M112 v6 and M113 v8 comes to mind. Probably the V12s too. The only downside is maintenece, but the coils rarely fails.

[@zanettiza8032]

My E55 M113k has dual spark plugs and being a 3 valve design its easy to locate them... Even before these modern engines Mercedes was using twin sparks in some of their engine but yes, Alfa is definitely the pioneer here.

[@woongah]

@@Rourkeize alas, at some point one has to replace the spark plugs, and I am told they are not cheap either... By my mechanic, who had bought my brother's w211 with the 2.6 litres V6.

[@johncunningham4820]

@@woongah . Modern Spark-Plugs have a very long Service Life . Brake Rotors need replacing from time to time too , as a Service item .

[@chiefdenis]

@@woongah they're not cheap if you give it to a mechanic to service them, in reality, spark plugs are probably the cheapest and easiest things you can do on an engine, and I've done spark plugs on an m112 clk, the only thing is you're now buying 12 plugs instead of 6.

[@Will-sc3hw]

My old 04 Honda jazz had a 1.4l 4 cylinder twin spark engine(DSI) . That thing ran amazingly well. At low rpms there was a slight delay between them. At high rpms they fire simultaneously.

[@CyroTheSpider]

Indeed, I remember that tiny engine had an amazing amount of torque down low for what it was. It was also decent higher up. The mileage was also great.

[@RJ9mech]

Well researched video! An item of note: in both flight training, and aircraft maintenance training we are taught that the primary purpose of dual ignition is to provide more complete combustion, and the redundancy is an important secondary purpose. (I personally could see it either way, and like the safety of having a dual system while flying.)

[@bushek502]

This channel got big really fast, i remember you having 150k like it was last week

[@DanielFrost79]

And you mean 'Bigger'. It's growing and at this rate it's not long until it has subscribers in the millions. Sadly that pretty much depends on viewers these days and if they have the balls to actually thumbs up the content they enjoy and are given for FREE.... which is a very low chance nowadays.

[@sam08g16]

One word: quality

[@idus]

Yea didn’t he have long hair before?

[@DanielFrost79]

@@idus Yes, he did. 👍

[@StratfordWingRider]

On a different note - the Honda Shadow 750 (VT750) has twin spark, both in carb and fuel injected form. Those are wonderful bikes and very popular. I’d happily delve back into twin spark for that bike.

[@kulbiznic9168]

Had one, great bike.

[@Alexander661]

I had always understood the use of two plugs in any engine with a hemispherical combustion chamber was because of inherently poor flame propagation in hemi chambered engines. Which I imagine would give you more flexibility in timing curves.

[@professorneturman2249]

Nitro engines are around 60° of advance

[@watajob]

Man, it's taken a long time but I finally caught one! The newer 5.7/6.4 Hemi do have variable intake length runners. And, my beloved 3rd gen Hemi retains most of the advantages of a "true" hemispherical combustion chamber w/o the flame front problems associated with the domed pistons usually required to maintain a decent compression ratio.

[@Oddman1980]

4:37 I don't know why, but this is, to me, one of the craziest things - cars going down a highway are moving faster than the explosions in the engine. Excellent video as always, I always learn something. I have a Suzuki DR650 with dual spark plugs, and I'm almost positive it's that way for redundancy. It doesn't really spin that fast, and the plugs are close together, and a DR650 is exactly the kind of bike that you're going to drop in the woods, which could break a plug.

[@d4a]

An important factor is the the area they have to cover. Combustion only has to cover 50-60mm and it's doing 16 METERS per SECOND. Whereas cars have to cover hundreds of kilometers and are doing 120 kilometers per HOUR. It's important not to imagine combustion as an explosion. Explosion is uncontrolled and a detonation. Combustion is controlled and it's deflagration. Hydrogen engines are dealing with far less controllable conditions for example and their combustion does close to 50 m/s at 1500 rpm.

[@waynegarfield6607]

The same reason a supersonic bullet can be accelerated faster than the speed of sound while black powder and even modern smokeless burn or combust at subsonic speeds. The air is heated and expanding faster than the burn rate. Plus at higher temps and higher pressures the speed of sound is increased. Physical properties and behaviours change with pressure and temp and we assume from our daily observations within a narrow window of temp and pressure that every chemical reaction or state of matter remains the same. On planets on our solar system it can be so cold that gases on earth become solids and become rain or snow . Look what water does solid liquid or gas within 180 degree F difference. We cant fathom steel evaporating or something boiling at super low temps like. oxygen. Inside an engine is a unique set of conditions that causes normal atmospheric combustion to behave differently

[@802Garage]

I have a dual plug car! My 1985 Datsun/Nissan 200SX. My S12 has a CA20E. Definitely not a powerful engine, but it scoots the lightweight car alright. One interesting point is that the plugs are on either side of the head. They use a one step colder plug on the exhaust side than the intake side. Pretty clever I thought!

[@analogwings]

In aircraft engines, if a magneto fails in a dual magneto engine, you lose 4 spark plugs (in a 4 cylinder engine). The unburnt fuel then quickly raises the exhaust gas temperature and one would have to reduce power. I guess it's better than losing all engine power! A single plug going out is less of an issue but it would result in a rougher running engine and this would be obvious if you had an engine monitor. It wouldn't be good to run it this way for an extended period of time. Thanks for your videos, they are very informative.

[@zodiac0545]

Excellent description of a complex subject , this channel gets better and better , keep it up and thanks , much appreciated

[@nobenznofun9139]

Was pretty common on all Mercedes V engines from late 90s to mid 2000, namely M112, 113, 138 and 275. Nice vid and great explanation.

[@larszenthio1012]

About 15 years ago I had 2 (!) Nissan Prairie m10 4wd 1988 model year. A blue that I drove with and a white as a spare car. These were not so common, so I found by chance one more just weeks after I bought the first one. It was a 2.0 engine of 100 hp with double spark plugs and two ignition coils. I regret today that I sold them. A very practical car with sliding rear doors and no doorpost between front and rear doors. Easy to load. Perfect winter car and fun to drive.

[@chir0pter]

I love how clear and simple the diagrams are, if you don't get it at 5:21 pause the video for 3s and look at how the diagram perfectly illustrates pre-ignition- the flame front reaching the upward-moving piston while the other half of the cylinder is unignited!

[@chippyjohn1]

He is actually describing detonation, not pre-ignition. Detonation after spark fires, pre is before.

[@AgnotologyTV]

First car, 1989 4 cylinder mustang. I called it "four angry cylinders" 8 spark plugs, 88 horse power. I genuinely cannot fathom how they managed to make such an anemic engine from 2.4 liters of displacement. I wish I still had the car, would have loved to swap a mid 2000's SVT focus motor into it.

[@bobhill3941]

When my grandad was a 15 year old apprentice mechanic in England in the early 50's, he told me of a 1911 Isotta Fraschini Prevesi Creps chassis touring car. Black, 16 gauge aluminum body. The straight 8 had duel distributor and magnito ignition.

[@jonpitt8504]

In 1957, Maserati introduced its first full-production model, the 3500GT. Its engine was a detuned version of its straight 6 racing engine, as used in the 350S, which featured twin plugs. The 3500GT used twin-plug ignition from the start, coupled to triple Weber sidedraught carburetors. From 1962 it was also fitted with Lucas fuel injection . . . . and became the first car ever to be called a 'GTi'. Later 6-cylinder models, the Sebring and Mistral, used the same set-up in larger 3.7 and 4.0 litre form, and featured the script 'Iniezione' on the back. The power was quoted as being 15 bhp more than the carb versions, which supports your video analysis. Good video, btw.

[@colinsk8s]

Thanks for explaining this so well! I work on motorcycles in SEAsia, and came across the twin and triple spark Bajaj models here. I was curious why, and now I know!

[@Bren.nto6971]

India pulsar motorcycle has 3 spark plug per cylinders, good performance and low gas consumption, 1L / 2 weeks

[@glynluff2595]

A good explanation. The initial concept of twin plugs was to allow constant ignition on aero engines because early plugs were very temperamental and would often fail on take off or over enemy territory. The advance of flame front on early engines was little understood as these averaged between 1200 and 2000 rpm. Post First War research by K lee Guinness KLG proved the validity of his mica plugs and manufacturers research developed flame front technology and raised rev limits. These were usually magneto operated and there were safety limits on the drops allowed. This was 400 rpm on the Rolls Meteor which initially were lifed out Merlin engines but later were made in their own right. What you have to remember is that in 1914 the only reliable magneto was made by Bosch. So at the end of the war all the magnetos made by the Allied powers that used Bosch principals of design had to make a payment to Bosch. This happened in WWII as well as all the French factories bombed by the RAF and the American Air Force as well as American factories in Germany were given financial compensation. The factories here that created the magnetos and other instruments of war were taxed very heavily for excess profits from government contracts.

[@spootneo64]

Correct me if i'm wrong, but recent direct fuel injection have never been made to optimize homogenization. Carburetors were in fact quite good at it, even though they were mechanlical devices. Single point injection was also good at it, since the air-fuel mixture had to travel the whole intake manifold lenght before reachng the cylinder. Direct injection were optimized to run lean mixtures, but they are particle emmiters compared to older solutions, because of unmixed gas being burned in the cylinder. Otherwise your videos are great, and it is really amazing to find such detailed explanations on youtube, keep up the great work ! I believe your accent (and subtitles) also help non-native english speakers understand your explanations.

[@johncunningham4820]

Direct Injectors operate at VERY high Fuel Pressure that Atomises the Fuel basically Instantly . Into a Pre-existing Fire .

[@spootneo64]

@@johncunningham4820 gasoline injectors don't. "VERY high" fuel pressure is 2500Bars Diesel, and guess what ? They produce particles too. Also the goal of lean mixture engine is not to have a "pre-existing fire" but rather a pre heated air pocket, not hot enough though to get pre-ignition nor knock

[@johncunningham4820]

@@spootneo64 . Ah ! Tech Talk , huh ? Diesel Injection IS the Ignition Cycle for that type of Engine And Yes EXTREMELY high Injection Pressures . Stand Alone Direct Petrol Injection is at Very High Pressure , for fast atomisation and SHORT duration , at very slightly before the Spark Event . And Dual Injection , the Direct Injector WILL be adding to the Already burning Port Injected Fuel . I personally LIKE Properly Set Up and adjusted Carburettor(s) . And a Digital Ignition to go with it . More reliable and No Reason it can't be just as economical AND clean burning . Just needs Care-Taking .

[@khalilveronessi4819]

I had a Bajaj Rouser (pulsar in other countries) 220F , it's an Indian motorcycle, it had two spark plugs that worked simultaneously.

[@abhishekwellage215]

That's because it's a 2 valve engine and the goals were to reduce emissions and shorten the ignition time. The one in this video has a 4 valve engine with three spark plugs that gives a spark in 2 different times (two plugs simultaneously and one separately).

[@ElPabloDelDiablo]

I have an Alfa Romeo 156 with 1.6 TS as my first car and I absolutely love that engine!

[@chiefdenis]

This man said all that good shit about twin spark engines and never even mentioned all the incredible mercedes m112, m113, m275, etc. Engines that used such design to it's best potential, reality is often disappointing.

[@Simoxs7]

My 3rd Motorcycle was a BMW F650GS single cyclinder from 2006, they added a twin spark system in 2004 and apparently it reduced the fuel consumption a bit as well as reducing emissions..

[@geoffmesser5091]

Mine is a 2007. The dual spark/fuel injected Rotax engines were a big improvement over earlier models in performance as well as better fuel economy and reduced emissions.

[@dionisis0018]

I have a Kawasaki kle 500 parallel twin that revs to 9.5k rpm and I've seen examples of the gpz 500 that has the same engine but differently tuned, revving to 11k rpm with a single spark on each cylinder. I don't know the point I'm trying to make,I'm just mentioning the fact. Great information btw,great video.

[@ericjohnson5662]

What? No mention to the Toyota 3T-GTE. You’re great and I appreciate you. As a fellow classic Toyota enthusiast, I’m bound to say this.

[@mfslyphantom8811]

I’m sure it’s here in the comments somewhere but if it isn’t one of the main reasons for the 2 plug setup on aircraft piston engines is because of the potential for fouling due to the use of leaded gasoline (or oil fouling if your engine has shitty rings or valve guides because you decided to “enjoy” extended service) You covered just about all the other benefits that I know of.

[@brentboswell1294]

The 2.3 Lima engine in the North American Ford Ranger had twin spark plugs starting in the late 1980's. I believe that it followed the introduction of multiport Electronic Fuel Injection on that engine...

[@trinidyjohnson9295]

Dude you truly have a gift of taking something that can be complicated and explaining it simply....... Kudos to you my friend

[@stefansommers]

Hello, I must comment on the alfa romeo CF1 and CF2 twin spark delivery....on research you will find the coil on each spark plug delivers spark to the firing cylinder and the opposing exhaust stroke cylinder.....just look at the spark plug leads....both at the same time.....this was done for emissions by burning residual fuel in the mixture about to become exhaust gases.....also allowed for a richer mixture whenever needed, by being corrected on the exhaust stroke for emission clean up.... Alfa mechanic for 50 years, stefan.

[@hollander133]

First good video and explaining some good resons to have twinspark. Tough so far as I understood why Alfa Introduced the 2.0 twinspark is that the old twinspark was now on par with the 1.8 injection so the engine needed an upgread. Fiat did not allow to big changes to the block but there was enough money for a head revision (money as alway's a big thing at Alfa) Here Alfa rememberd this thing from their race history and decided to put it into their cars as a preformence upgreade.This system improving compression (1-11.5 if I remember correctly) and with injection and variable timing made a very good engine. And the 75 twinspark saw high sale numbers. With the later 16 valve engines there was no need for the 2th plug as the plug was not in the way of the valves, so the engineers reduced the plugs to 1 per cilinder, untill the commercial side took over and forced a 2th plug in there. So technically the yougner twinsparks are a sales technic still sailing on the succes of the original twinspark. As I have owned an original twinspark, I can say, they were definitly a really good engine and right for the car it was placed in.

[@alexjenner1108]

From my understanding, those older 8 valve twinspark engines (e.g. Alfa 75) had a narrower valve angle than the earlier 8 valve twin cam engines (single plug). This narrower valve angle was possible because twin offset plugs replaced the centrally located plug in the older engine, so improved combustion chamber shape was another benefit of the design.

[@hollander133]

@@alexjenner1108 This is what I ment, tough trying to keep it a little more generic and more easy. But you are very much right on this.

[@ar33turbo]

In Alfa 75, twin spark engine was born before fiat bought Alfa , had 148hp - same engine with no twin spark has 128hp, it's significant difference, then in 145/6,156/6, gtv.. was on fiats block with alfas ts 16v head and had nothing to do with old full aluminum engines...

[@jaybee5390]

For combustion its important to burn fuel air mixture equal and central as possible. Caused of waves spreading from ignition. For some constructions it is better to use 2 spark plugs. For example in big ass hemispheric heads with two valves. In some aircraft engines it has its safety issues too.

[@jereomen]

My 2014 ram with the 5.7 hemi indeed has a variable intake with it’s dual spark plugs. The truck 5.7 engines have variable intakes or at least the gen 4 engines do.

[@vukmandusic9359]

The first manufacturer and constructor, who installed 2 spark plugs per cylinder, was ETORE BUGATTI, on the model BUGATI ROYAL ... Mercedes had 2 spark plugs per cylinder, on engines larger than 3 liters and when the engine was cold, first the electricity was distributed to 1, and then, after a few milliseconds to another spark plug, and when the engine warmed up, there was a simultaneous distribution on both spark plugs ... TWIN SPARK design solution, proved to be good, because it increased engine power, had higher fuel efficiency and thus lower consumption, and with this solution, must be considered a very important design solution SQUARE AND SUPER SQUARE engine, where it is very important, which is the ratio of piston diameter and stroke / when the piston stroke and diameter are the same, it is a square motor, and when the diameter is larger than the piston stroke, it is a superquare motor - such motors have a longer lifespan, due to the average piston speed per second is the utilization and consumption of fuel ... Alfa Romeo has always preferred the construction of a super square ... These combinations always give good results In addition, the quality of the intake air in the combustion chamber is important ... Alfa Romeo has always made the KALOTA chamber, but the engine is a bit hard, due to the strong line of power development ... There are other solutions, which together with this, give even more power and less consumption, compared to only 1 spark plug ... For example. PORSCHE has managed to solve the problem of ratio, vacuum, temperature and engine speed, so that, depending on the operating mode, it always has a variable suction channel and suction speed, gets the best stoichiometric ratio and maximum power, at all times, according to speed ...

[@robertjongen7615]

Legacy aircraft piston engines also have 2 spark plugs that have their own ignition system, called magneto's. You can run them on both, during the start you have to run them both and each independent to verify if both systems are working properly. If you run one system you have a rpm drop between 50 and 100 rpm at 2000 rpm (= +/- 50% power, you have propeller up front that needs power to be able to reach 2000 rpm.

[@edsmith2562]

If I read you correct, then Harley installed 2 plugs per cylinder begining in 2017 on the M-8 simply to run then as lean as possible (cleaner) at >10:1 C/R. And they do run super lean and hot as ever.

[@Odin851]

My CL600 with the M275 motor uses twin spark. Gonna need a day of mental preparation when I have to replace 24 spark plugs 🥲

[@Nick-GR]

All Twin Spark engines had Phase variator not just the CF3. And from CF2 and onwards they had the variable intake flap too (only for 1.8 and 2.0lt engines).

[@mikhailjairnisbett441]

An inportant thing to note here is that airplane engines generally dont have ignition coils, they have magnetos that can operate even in the case of a complete electrical failure. These are engine-driven by a gear and can keep the engine running as long as it has fuel, no need for a battery or electrical system. In the O360 engine that i use every day, there are two magnetos, one for the 4 upper spark plugs and the other for the 4 lower ones.

[@charliedee9276]

Early 80's Mazda B2000 pickup had twin plugs as well, may have been a B3000. I was in the service then, it was a friends truck. I run twin plugs on my old Harley Sportster, 45 Degree valve included angle means a huge dome piston, the plugs are on each side of the dome. Harley even did it on stock Sportsters in the late 90's on the "S" model 1200.

[@phantomforester9337]

The Mercedes 1914 GP engine had four valves per cylinder and three spark plugs. There was an experiment done with something like more than 10 spark plugs in a single-cylinder L-head engine--it was covered in SAE Proceedings, in the 30s or 40s (?). Different settings were used to vary how many spark plugs were activated for comparison purposes. I believe there was no worthwhile advantage found for firing multiple plugs. That L-head, I believe, did not use the Ricardo turbulence combustion chamber arrangement--the whole space below the head was used for combustion.

[@yuseung]

on the KTM 1190 motorcycle, there are 2 plugs per cyclinder (one large, one small) the dealer claims one plug for low speed & smoother running... the second plug for higher speed running... it is possible to verify this claim ? thank you for the content produced .... always engaging to listen !

[@andypaine7489]

Once again with your site I went to school - Grad school!

[@luftstolle]

Wow, I'm even learning about airplanes now on your channel! Awesome!

[@Xenstein]

Until recent the Smart cars had SOHC twin spark engines who managed outputs over 80, 100 or even 125 bhp from a 3 cyl turbo 700 cc(0,7 liter engine). Twin spark engines are more common than you think

[@DrJRaven]

In 1963 Maserati Sebring used a twin overhead cam 6 cylinder engine with twin spark plugs. I also need understand Mercedes plaid around with twin spark plugs as well.

[@tonylam9548]

You forgot the Mazda rotary engines , with 2 spark plugs. The other reason airplanes need another spark plug is airplane are RPM limited , so to produce the torque and HP necessary, they need very big displacements. Pistons are often 4 inches across, that means they have the space needed, and the second plug light up the mixture more efficiently, even if aviation plugs are twice the size as auto plugs. If one set of plugs failed in flight, there will be a loss of approx 15% efficiency, which is a drop of maybe 150 RPM ? There are experimental systems where there are just one plug and the spark came from dual spark modules, or just V8s with individual coil packs.

[@Orangepilldispencer]

One of my first Yamaha 2 stroke motorcycles has 2 spark plugs, but didn't fire both, it was in case of fouling one you could very easily and quickly switch to the other. My current street bike a Yamaha Raider has 2 per cylinder.

[@parsonscarlson7984]

Another great and informative video, but this one with a commercial. I can only guess that you have received some kind of sponsorship, hence the advertisement. You deserve it. Hope it helps and frees you to continue this online school of ICE higher learning. I always learn at least 2 things; that I don't know much and have a lot still to learn.

[@brmadhavan2000]

I have a 2007 Honda City iDSI engine that has twin sparkplugs. It's a 1.34 liter 86 HP engine. But I feel it has very good power. It isn't quick but never let me down while overtaking.

[@ronstiles2681]

Nice video sir, maybe a bit quick for a novice to take everything in. Not sure of the years but many hemi engines have dual plugs ,I think you missed them, and I happy you mentioned dual ignition on planes, one other thing explain heat range and spark gap ,and msd,ignition for the public, I think that might make a good video, keep up the good work

[@johnlucas2037]

I had a 1921 American LaFrance with a 600 ci 4 cylinder T head that had two plugs per cylinder. It sure ran better with two plugs firing than it did with one.

[@jamesaucutt8284]

I’m very happy you pointed that out about the airplanes I never realize they had that set up

[@alecjohn979]

Awesome video. Bajaj Dominar 400 uses triple spark. Amazing bike.

[@jay1st1st]

in 1996 my old Suzuki 600DR, a big mono had 2 spark plugs as well

[@Gord1973]

I currently have 2 twin spark engines in my driveway. A 2015 Ram 1500 Hemi as well as a 1985 Honda VT1100C V-twin motorcycle. Honda made that particular model for model years 1985 and 1986. I don’t know If the redesigned VT1100 from 1987 onwards also had a twin spark engine or not

[@blkdna748]

We go DTSI engine in bajaj pulsar motorcycle. 1st they introduced twin spark. Now they introduced triple spark too.

[@PaulKind3d]

DR650's carry a dual sparkplug on a big single. I have always assumed it was to make it combust quicker and more thoroughly and also why they likely do amazingly with just about any kind of fuel you put in them.

[@CarlosAp27]

My Suzuki V-Strom 1000 has twin spark plugs. Great vídeo.

[@martinheijden1418]

The engine of the older smarts also have dual spark plugs. Although those are nowhere near each other. I wonder how that works.

[@brandoncraig392]

Could you do a video comparison of twin spark multi spark sparkplugs and pre ignition chamber ignitions.i want to know which is best I would also like to know if pre ignition with a added spark plug other than the main spark would work better and how.

[@marcelgombault3657]

The twin spark came from engine combustion designed heads. Alfa Porsche air cooled and the Hemi head in the US. You also mention Mercedes. The problem with a hemispherical combustion chamber is you had a domed piston and a hollowed out head, so the piston goes in deeply into the head. this made it easily that parts of the spark are blocked from fuel. That is why all racing porches cars changed to twin spark to prevent knocking.

[@29madmangaud29]

that's why PULSTAR was created. I'm sure you know of/have heard of Pulstar Plug. They've been added to all Toyota Prius' since 2010, I believe. The are a capacitor plug that has super high, super quick flashes. I use them on all of my families cars. (2 motorcycles, 2- 4cyl cars, and 1- V-8 truck)

[@Pirreren]

My 2013 Honda Insight 1.3 has dual spark plugs.. found this out yesterday when i was changing them. So now 4 out of 8 have been changed 😅

[@AntonioBarba_TheKaneB]

Suzuki DL650 V Strom, model year 2007 has two spark plugs per cylinder. I don't know if other versions have two sparks also. My old 2004 only had one per cylinder.

[@Blockbuster2033]

The Suzuki SV650 switched to a twin spark somewhere around 2005, if I remember correctly, not sure why tho.

[@jonnijames]

Let me tell you i only had to rewind one parts once because it was too heavy to sink in on the fly, ahhahaha you are a genius~!!!

[@tturi2]

What about putting passive pre combustion sparkplugs into cars that didn't get them stock? with tuning of course

[@_gramcrakka_82]

The 5.7 Hemi engines run twin plugs if I remember correctly

[@screddot7074]

My Honda VTX1800T has 2 plugs per cylinder. Only motorcycle I ever owned that I felt like I needed a seat belt when I rolled the throttle.

[@icantbelievemylife_2792]

Love the ICT-34 at 10:45. Have dual ICT's on my Beetle lmao

[@Backyardmech1]

It’s not just about engine efficiency, but redundancy with the ignition system. Not going to deny the performance advantages, but with automotive engines, valves occupy the space the spark plug can effectively work.

[@LujinCustom]

One of my dad’s friends had a Datsun pickup truck with dual spark ignition. One plug was hotter than the other.

[@deltacx1059]

4:36 or just how large the chamber is. A 50cc engine has a tiny chamber and a 400cc engine has a much larger chamber so the front takes longer to get across the chamber.

[@riedjacobsen8620]

Some Corvair engines converted for experimental aircraft sometime have dual ignition systems on single plugs. Dual ignition redundancy without the hassle of drilling a second spark plug bhole

[@Oldsmobile69]

What if I want a TRI-SPARK!?

[@maxwell-style4584]

Chrysler has been using this design in the Hemi since the early 2000's; and it's still in use because of how efficiently the sparks ignite the fuel.

[@kainhall]

wrong . the 2nd spark is a delayed a few MS.....and its 100% for emissions NOT for performance . the 5.7 chamber is not even CLOSE to the same design as the WW2 engines and the 60s and 70s HEMI

[@Bartonovich52]

Yep. It’s a semi-hemi because there’s no way a true hemi would ever pass emissions. The second spark plug is to clean up the emissions. Dodge knew it was obsolete back in the 50s when they designed the wedge head to replace it.

[@maxwell-style4584]

@@Bartonovich52 Not the case with the Gen3, they fire together.

[@kainhall]

@@maxwell-style4584 but they use the same coil packs...... . So I'm pretty sure ya wrong

[@caty863]

Once I owned a motorbike from an indian manufacturer called Bajaj. They have a technology called DTSi that involves 2 spark plugs. I don't know what it does exactly, what I remember is that it once save me when I parked my bike in an unsafe place and one spark plug was stolen. They guys who stole it were around watching me, waiting me to ask them for support lest I would get stuck there. It shocked them when I came back, found that the plug was stolen, but still went ahead and turned on the bike, and off I rode. I felt very good to disappoint and humiliate them that much.

[@delahayenator]

Alfa Romeo introduced the twin spark principle on the bialbero engine already in 65 when the 105 GTA 1750 went into production

[@adaml2023]

I want to hear more about the engine at 3:15! Does it have seperate compression and expansion cylinders?!

[@snikwadRR]

No mention of MBz. Mercedes had twin spark engines thru the 2000s. The M113 and M113K for example have 16 of those bad Jacksons

[@andylaurel]

The Suzuki line of V-twin motorcycle engines found in the SV650 and V-Strom use twin spark ignition. I think a benefit of twin spark is greater on short stroke big bore engines to get a better flame front distribution.

[@jimbillyjenkims]

So who had variable intake runners first? BMW had them from at least '99. There's no climbing onto the cam, they're completely linear. It's all, "TORQUE!!! NAOOOW!" (Granted, I don't know how much their VVT system affects that, so take that with a grain of salt!) I'd love to see a video on the development of these systems!

[@seanchin4481]

Cool video, love your work. Can you explain why a distributor would have two points and two condensers? I have a 1971 Fiat 124 1.6l twin cam and just got a distributor from a 1978 model and the new one has whole extra set of points and condensers. They both only use four spark plugs. Also should I install the newer distributor on the older car?

[@robertmaitland09]

My old Aprilia RSV 1000 Tuono had twin spark plug heads in a 60 degree 8 valve v twin, interestingly the engine was built by Rotax who make aero engines.

[@alexlukas2817]

Tnx a lot was waiting for a long time to see a Video about the Alfa TS !!! Tnx

[@scottyd980]

My 2007 Suzuki motorcycle has twin spark plugs. V-twin 650 with 2 plugs per cylinder.

[@inaNis_]

The Toyota 3t-gte and 4t-gte which powered the group B Twin Cam Turbo Celica also had twin spark plugs.

[@cyronader]

Mercedes m112 and m113 engines had twin sparks. Pain in the ass to replace.

[@darknutgaming5510]

My Ford Rangers all have twin plugs, but one is in the cylinder and the other is in the exhaust manifold to burn off any unspent fuel

[@georgiosxirouchakis439]

You forgot the most important engine M112 and M113 V6,V8,V12 in all version for a lot years more than 10 years..Greeting’s from Germany.

[@observingrogue7652]

What about 2stroke engines? No valve space to worry about, and there are dual plug motorized bicycle heads available.

[@Tony_-vp8ys]

The use of twin spark technology might not have gained a widespread use following Alfa Romeo's recent use, but it's certainly not technologically passé following Maserati's use of twin spark in their MC20 engine. I wonder what gains Maserati have found with using twin spark...

[@thomasheer825]

twin plug systems are not new, Abarth made dual plug heads in the late 60's. There were numerous aftermarket manufacturers that made or modified your head to operate with 2 plugs, was very common with Harley and BMW boxer motors. So they were around at a fairly common operation. Often these plugs even on these older engines with often point ignition had the firing off by several degrees. Now days this is absolutely normal, in fact there are some systems that allow the plug to fire several time.

[@victorjohnson7512]

Twin spark plugs goes all the way back to the 1920s in early race cars.

[@raygale4198]

Royal Enfield motor cylces also used dual spark on their UCI engines.

[@AfonsoBucco]

10:32 let me see if I understand the joke: some VW engines are today using stratified injection, indirect AND direct injection. So they can purposely use heterogeneous mixture in a good way. They create a heterogeneous mixture if you are talking about the entire chamber, but actually they create an homogeneous mixture close to the spark, so it's possible to use a poor mixture in the rest of chamber unless being incomplete combustion, once the homogeneous mixture close to the spark will to the job of firing everything.

[@almfreak]

Excellent video! Very Informative and thorough, as always!