HEMI ENGINE - GREAT

[1066gonzo]

The straighter the flow of the intake and exhaust gasses the more flow through the head. The HEMI head excells in the efficency of flow. The angle of the valves is EVERYTHING to all engines This is the reason that all of the top pro classes in dragracing use a HEMI or variation of the hemi engine for the most power possible.

[EngineeringExplained]

@1066gonzo What do you mean by "straighter?" I'm assuming vertical with the cylinder heads? HEMI's are actually quite difficult to orient valves compared to a flatter pentroof design, which also allows for 4 valves, meaning greater airflow.

[DeAdiSSu3]

@EngineeringExplained If you look at the rim of the intake/exhaust holes (not the ports - the holes where the valves sit when they aren't open) on the 426 hemi, you'll see it's a better angle for flow as opposed to a wedge-shaped combustion chamber's valve position.

[EngineeringExplained]

@DeAdiSSu3 Perhaps, but 4 valves per cylinder more than makes up for the loss, much better airflow, especially at high rpms, in comparison with a HEMI. 

[DeAdiSSu3]

@EngineeringExplained Then again, you're talking two different eras. The 426 hemi was, in my opinion, the best use of cubic inches out of all the American v8's until the 2011 5.0 came around lol

[GXArmagedonPL]

fucking music .... put here engine sound!

[OldboySaint]

Chrysler calls these new engines "Hemi" but they aren't really Hemi by design, it's just another selling pitch.

[Daschickenify]

What hemi? A hemi means that the top of the pistons are hemispherical, hence the name hemi.

[68bobba]

@Daschickenify The combustion chamber is hemisphereical in shape....thats where the name come from,not the top of the pistons

[dropkickmurphy01]

yeah that's not a hemi.

[CarboNHeaD123]

I'm confused, I don't understand what makes a Hemi so good. I've seen the engines on stands but I never really got why they are so good. Is it because of the amount of power they produce?

[MrCcc2000]

@CarboNHeaD123 yeah the produce more power because of how the valves and spark plug are place better flow and fuel is easier to ignite but the new ones aren't a true hemi

[killmast3r1]

@CarboNHeaD123 and the shape of the pistons are like a sphere that's why they call it a hemi it means hemispherical and i can remember why but for some reason the pistons make more power or something.

[adokenk3nnbasil]

nicee...

kool song

[MowagW200]

This is a very good animation. I think it's the actual 345 HEMI according the valve cover /w the ignition modules on top of it. For sure it's a very good engine, but nothing compared to a gen I HEMI (331 ... 392 cid).

[BumbleBeeGS]

That intro and piston thing looked bad ass. do it with a real hemi next time though.

[81lego81]

I like the old 7.0 HEMI better

[prima5driver]

do you mean the 426 ?

[bam6474]

Did you guys know that the Climax gas engine company built the the first Hemi one cylnder engine back in 1896!!!

[fordboy111591]

did u knw that the actually first good racing hemi engine was built in 63 and they found that the old wedge still blocks was crackin and chrystler ended up re designing the whole hemi motor and that next year hemi wont at daytona 500 in 1964

[68bobba]

@fordboy111591 The 426 Hemi debuted Daytona 500 1964...(took 1st,2nd and 3rd too)....they had to make thicker walled castings because the first blocks they cast kept cracking under race profile testing....It was based on the 426 wedge engine

[sookoll23]

how did you make this btw?

[sookoll23]

I've heard this one saying and... wth, you gotta admit its right...

Horsepower sells cars, torque wins races :)

[baldandold]

its TORQUE that moves cars, not BHP, Grunt vs Momentum almost

[GeneralCuster14]

Its a Hemispherical Combustion chamber that makes all the difference. Pure American Muscle. Nothing like it in the world ;)

[dancyou2b]

u got that right! :D

[logic2reason]

i would agree that what used to separate a hemi from the rest, is not long gone. a hemi today is nothign but an overpriced badge. but like vtec and other various cover up names to just raise the price. sure they all work. but everyone has the stuff. you just pay for your particular name. i mean shit. even my econobox honda has a hemi head design. why? becuase it makes sense. but the whole war on who did it first or who is better is nothing but a waste of time.

[Tubeworn]

WOW her ttits are reALLY nice! just like mine! b

[marquenda]

This vid made me sOOoOoOo wet LOL u

[yorrickhunt06]

there is nothing good about the hemi design. Except maybe that it gives all the idiots something to pull themselves off over. Keeps them away from animals and small children

[mopar43v3r]

it has a much larger quench area, more power, cam higher in block, higher rpm, no intake valve guide in the intake port, more flow=more power, so whats so bad about it?

[sspat1976]

your an idiot and i wouldn't talk, you don't know anything about engines. If you did you would know the hemi engine is legendary, one of the most successful motor ever designed and holds records on land, sea, and air. The proof speaks for it self look it up. Your just a hater cuz you don't have a 426 hemi like Me.

[TheDrakenZ]

lol, hemispherical heads man, it's revolutionary. You couldn't tell your ass from a hole in the ground so i dont see how you can make that comment.

[50chevyguy]

Far be it from me to claim their good!

But yeah, they suck because you can build in excess of 2000-3000hp, and on a daily driver, beat the piss out of them and they work after 40+ years.

LOL. Dipshit! If there's nothing good about them, WHY are they still used in race cars, dragsters?

And why does the most renowned F1 engine buiulder, "Cosworth" use the 426 Hemi as a base to build off!?

Go back to school!

[yorrickhunt06]

Lol, mate I dont know where to start....

I've never heard of a 2000-3000 hp daily driver anywhere, and if youre honest you probably havent either. Let alone one which has been going for 40 years.

They still use them in drags out of nostalgia, just like they dont allow computerised emgine management or launch control, to keep the whole thing intersting for the tuners. Dont think cosworth is big in F1 anymore. They certainly dont use a 426 hemi as a base for a F1 engine.

[50chevyguy]

Well, you miss read one part they can build a 2000-3000hp car, AND/OR on a daily driver basis....ect.

Most I've seen in a daily was 1000.

Local '69 camaro w/ racing 572.

And my grandfather had his near 40 years, never touched it or took it in to a shop.

Still ran...though not as well as it could have.

No, they don't anymore.

Not sure if they are either, don't pay much attention to F1.

Keep it interesting for tuners? How so?

Australia, correct?

[DodgeCharger91]

it is never the good motor product...American horses, to dream for us European

[TheDrakenZ]

LOL ur fucking hillarious, imports had to make a car that could take a corner like a champion because they knew their piece of shit pussy little cars would never be any match for american muscle in a race down the strip. Telling a muscle car to take a corner, or telling an import to perform well is like telling a pen to write in pencil.

[DodgeCharger91]

it excuses I don't speak well English, I wanted to say that hook the American horses

[laurence265]

this was cool but i thought it was the 426 hemi till the intake manifold went on :( lol

[brewil]

oh yeah i forgot. fastest naturally aspirated 6 in the world at the time. killed the porsche 911s

[brewil]

Australian hemi 265 straight six engine made 302 hp out of the factory in 1972 with 3 dual throat 45mm webers. theyre up to 400 horses and its only a six cylinder which makes great horses compared with a v8 as its lighter. 0-60 in 6 and 1/4 mile in 14.1 -1972 stats. just look up valiant charger e49.

[mopar43v3r]

people have had e49s do 0-60 in mid 5 and quarter in low to mid 13 on modern tires.

[LAtexStretch]

Forgive my lack of knowledge, but I still don't understand what's so special about the Hemi.

It just looks like a V engine layout.

What are the main characteristics of a hemi engine.

Like a Flat Inline 6(bmw), Boxer engine(subaru), V4,6,8,10,12.. and also the w12 like in the Bugatti.

Please someone explain.

=)

[bb4jdmlude]

the hemi head is hemispherical with domed pistons. with the spark plug in the dead center of the engine. so the valves dont have any shrouding to restrict the flow of air and gas and exhaust from the engine. also with the hemi head the spark plug ignites the center of the fuel air mixture instead of 1 side of it

[LAtexStretch]

Thank you dude!

[XxXFPSDougXxX]

Also when the mixture is ignited, it pushed the piston straight down because the burn is evenly distributed over the piston, which makes it highly efficient, and the 2 huge valves don't hurt the breathing. A big block capable of making 7500+ RPMs with a solid cam/lifters makes for one hell of an engine.

[22trol22]

HEMI is shit only big cilinder capacyti 5,7 and 6,1 L :(

[gracilicious123]

hey, my name is hemi actually...

sorry, random comment~

[iainthornton]

they stopped making the original Hemi firstly because it was never a great seller as it was expensive and so it wasn't worth the work to make it suitable for the impending emissions regulations

also this would undoubtedly have compromised power and torque which would have diluted the Hemi nametag-it remains today a classic BECAUSE they stopped making it

throughout its life it produced an honest 425hp (or more)...and discontinuing it ensured it would do so forever

[duleknife]

all you guys talking smack about the hemi. it still dosn't explain why they are kick ass. i think the only people who try to find problems with the hemi are people who got tired of hearing how some Mopar kick their favorite car brands ass. the only real problem with it was that all that power came from somewhere. Gas. hemis were gas gusslers. but nobody cared back in the day. power was more important to the car buyer then fuel economy. Sucks gas and hauls ass!

[philipp122]

See, and look where it's brought the world. Now, we're running low on gas, and thanks to those gas-sucking, inefficient, overrated motors gas prices are soaring through the roof. Also, the only reason these hemis make power is because of their size. The fact that it's actually a hemi is actually a bad thing because the shape of the engine head gives it less compression and therefore, less power per displacement.

[duleknife]

due to the shape of your head there is less power and acording to your comment you have know knowledge of the HEMI engine. if it made less power how come insurance companys gave HEMI owners higher rates, how come it got outlawed in NASCAR for being unstopable, how come similar engine blocks of the same cubic inch displacment and fuel systems had an adverage of 85-115 less horsepower and 65-70 less foot pounds of touque? I assure you that i know more about MOPARS than you. go huge a hybrid.

[philipp122]

Actually, since the head of the engine is a hemisphere instead of a penthouse shape, the engine has more room for fuel for a set displacement since displacement is calculated with your bore and stroke and the volume of the engine head is not calculated in. You are using more fuel, but getting less compression. The best to make power is to use an actual larger displacement so you get both more fuel AND more compression. The Hemi is only an advantage when displacment is regulated (i.e. NASCAR).

[56stratocaster]

Penthouse? I thought that was a magazine. You are probably a loser Chevy lover or some green hybrid driver. Energy has to come from somewhere dingbell, and by the way we are not running low on gas! PS. It's obvious by your inept mechanical explanation above that you have no idea what you are talking about. DUHHHHH

[philipp122]

Actually, I happen to know exactly what I'm talking about. I'm sorry that you're unexperienced and couldn't understand what I wrote, but it's the truth. Hemis provide more power for the amount of cylinder volume they claim to have, but they make less power for the amount of fuel they use. The reason for this is that displacement is calculated with the bore (diameter) and the stroke (height) of the cylinderical shape that the piston travels. Head volume is not part of the equation.

[56stratocaster]

Head volume has nothing to do with the hemi's superiority. Parallel valve engines do not have the advantage of zero shrouding...they cannot flow the volumes of air that a dual rocker shaft engine can...the stock, off the shelf 5.7 liter hemi head flows on par with a nascar sprint cup head...look it up. The port velocities are very close to a formula 1 engine...look it up. And another thing, LEARN HOW TO SPELL!!!

[56stratocaster]

Just one more thing. The Chrysler Hemi is the greatest OHV gasoline passenger/racing car engine ever developed, period. Anyone who disputes that ignores history and has very little true mechanical knowledge. Restrictor plate racing came from hemi's dominance. Look it up.

[philipp122]

You don't seemto know much about engines. Today, Hemis are very uneconomical and unpractical. They aren't even close to the best engine design or quality. It has strongpoints and weakpoints, but all in all it's not worth all the hype just because of the shape of the cylinder head.

[56stratocaster]

Thats the problem with most chevy lovers. They just can't accept the fact that a company can design a better engine than GM. Hype? No hype, just results. I really don't know who you are trying to impress, but it's not working. It's real easy to hide behind a keyboard and type anything you pull out of your ass and I suppose some people will buy it but not anyone with half a brain. Just so you know.

[philipp122]

I'm sorry that you're so ignorant. I supplied you with real information and facts about the pros and cons of the Heni engine. You just talk shit. I'm right, you're wrong, get used to it.

[56stratocaster]

I'm sorry I got into a discussion with a chronic masturbater. You supplied half-baked bullshit. If you wanna play with the big boys, get your facts straight. Otherwise, stay on your porn websites. Oh, and you never denied being a chevy fag!!! hahaha

[philipp122]

You still haven't given me one fact about the Hemi that makes it better. It has a hemispherical engine head cavity, that's it. THat means more fuel because there is more volume in the cylinder at TDC with a set boreXstroke (displacement). More power for for displacement, but the most effecttive way to use that fuel is to actually increase displacement so you get the added compression of having a penthouse engine head cavity. Since increasing displacement was illegal in NASCAR, they used Hemis.

[56stratocaster]

Phillip, there are so many more factors than displacement. I will explain some. Please give me your undivided attention. The shape of the combustion chamber in a hemi is not relevant. When the engine was developed, in the 40's as a fighter plane engine, it was referred to as the "twin rocker shaft engine". This is the key to the Hemi's potential. The twin rocker shafts allow valves to be placed opposing one another as opposed to parallel, or, side by side, as in the "pent-roof" head design.

[philipp122]

That's not the key of the Hemi engine. That's one of the engine's characteristics. The main advantage is the larger volume of the cylinder cavity when the piston is at TDC, as well as a higher torque figure because more of the combustion force is directed straight downwards (another advantage of the hemishperical engine head). The Hemi's valve setup offers little to increase power.

[56stratocaster]

The problem with the pent-roof chamber is shrouding of the air fuel mixture. The valve configuration in the hemi eliminates shrouding and also allows the use of larger valve because the valve is at an angle, as opposed to crowded right next to the other valve. This is similiar to the "canted valve head" Ford developed but is superior due to rocker shaft/pushrod configuration. Contrary to what you stated, the Hemi's valve setup is exactly what gives the engine it's advantage. This is fact.

[56stratocaster]

We could debate this forever but until you do some research, this discussion will go nowhere. The key to the hemi engine is exactly the valve configuration and has nothing to do with displacement. The 345 cid hemi produced by Chrysler as we speak has an output of 1 hp per cubic inch. This is in unmodified, stock form. The redline is past 6000 rpm. It is not particularly fuel efficient but neither is any modern v8 unless one opts for mds. But nonetheless, hemi is king, just ask the king, R Petty.

[philipp122]

Ever heard of DOHC and variable valve timing? The intake and exhaust valves are at opposite sides of the spark plug, and using the available space was made possible with double overhead cams. Now, the entire width of the area of the head is used for valves because cars are running 4 or even 5 valves per cylinder. Also, VVT ensures a healthy, undistorted air-fuel ratio.

[56stratocaster]

Yes, and thats why in my initial comment I stated the Hemi was the most advanced OHV engine ever built. Of course OHC engines are superior, there are no pushrods, so as many valves as you can stuff into a head, they can all function. But no American company has ever decided to go to that expense. It would put American v8s on a level with Ferrari, Lamborghini and so forth. But it's not financially practical.

[philipp122]

OHV and OHC are two totally different things. All modern car engines, as well as most older car engines, are OHV. Don't even try to say that the Hemi is the most advanced OHV engine because that;s not even close to correct. Manufacturers liek Mistsubishi, Volkswagen, Audi, Mercedes, Honda, Ferrari, and Porsche are currently the top manufacturers when it comes to advanced engines.

[56stratocaster]

I don't have the time or the inclination to teach you a terminology class. The autos you listed above are OHC engines. No shit? You need a reading comprehension course. OHV is the accepted term for " pushrod operated, overhead valve engine." Now don't bother me anymore until you learn some basics.

[50chevyguy]

That's where you're wrong!

In the 40's, they were still using those pain-in-the-ass circular engines.

Keep forgetting the name of them.

Even then, a V8 was never used in a plane, only V12's and turbine engines-which were developed by Alison, Rolls Royce, and Mercedes in the mid 40's.

[56stratocaster]

Not the engine itself but the head design. your thinking of "radial" engine. You can have a hemi in any configuration; v6, v8, v12 etc. Chrysler Australia produced an inline 6 hemi. And I may be mistaken but I don't believe a turbine was used in the 1940s.

[50chevyguy]

Yeah, they started using them in the later half of WW2.

A very primative jet, but advanced for it's time.

An inline 6 HEMI!?

Where can I find one! I could use it for my '50 chevy!

[4thstooge]

@50chevyguy Chrysler of Australia built an inline 265 cu. in. 6 cyl. hemi. Some have been imported into the U.S.

[56stratocaster]

That is the purpose of the hemispherical shape of the head, i.e., the surface of the very large valves face each other in the combustion chamber instead of sitting side-by-side.

[chalomeo]

hahahaha chronic masturbater!!!

[iainthornton]

hang on....Hemis don't necessarily have low compression.the original 426 Hemi was 12.5:1 compared to the wedge heads Chrysler was making at the time which were like 8.5:1

the Hemi is a legend

DO NOT RUIN IT...hater

Mopar or Nocar!

[philipp122]

They have less compression compared to other cars with the same displacement and cylinder. The compression ratio is the ratio of the volume of the cylinder at BDC to the volume of the cylinder at TDC. The volume of the cylinder is measured using the bore and the stroke. So even with a 12.5 compression ratio, it still has less compression than a 426 non-Hemi with a 12.5 CR would.

[iainthornton]

true but my point remains-you would never really want more than 12.5:1 in a road engine. therefore even though the equivalent penthead design would have greater compression, you can still get as much as you want out of a Hemi so it's kind of a moot point

[Camaro2007]

Why not go with the classic hemi

[StrokerAce02]

they stopped making it because of the gas crisis, and rising insurance rates, which is the reason for all of the muscle cars departure, with new technology, they can now build the hemi for less while consuming less fuel than the 426.

[BassmentCuts]

HEMI RULES!!!!!!!!!!!!!!!

[BloodyFingerz]

thats a baby hemi.. not the original 426c.i. 7.0L big block..

[legend9898]

hmm clever i dont know screw it im busy now lol

[legend9898]

this is not a true hemi engine the cylinder heads arnt hemispherical so wtf???

[1thekeatonb]

it didn't even show the combustion chamber so you can't say it isn't a hemi

[anmesm58527]

the important part of hemi is the fact that the spark plug is in the center so that the boom pushes straight down rather than to the side with 98% of other engines and if you look carefully it is slightly dished

[philipp122]

That's actually not true. Hemis were unique because when it was developed, most cars were using flattop engines. Meanwhile, Europe was developing the penthouse engine, which is what most non-hemi cars use now. The Hemi has the advantage of more cylinder volume for a set diameter because of the hemishperical head, while the penthouse design has the advantage of 4 or 5 valve-per-cylinder design potential.

[philipp122]

Also, since the Hemi's advantage is their cylinder volume, manufacturers go ahead and make them very large. That way, they produce tons of power. Now, it is a common misconception that Hemis are "better" than regular engines, when inm reality it is only their massive cylinder volume that makes all that power.

[anmesm58527]

ok, good point but how does that not make what i said not true? the angle of combustion is one of the most important factors in why the hemi is more powerful than an engine with the exact same displacement. what you are talking about is just "hemi's have more displacement", well most hemis are 5.7s and i've got a 5.8 chevy smallblock so, where'd your point go?

[anmesm58527]

and if you were talking about the upper part of the combustion chamber(the area in the head) then im going to just ignore your opinions from now on, cause more room in the head of an engine actually decreases power cause you lose compression. the hemi's power comes from the fact that it pushes straight down on the piston instead of one corner of the piston. i will give you the fact that your first post was a nice history lesson, but your automotive science lesson came up a bit short.

[philipp122]

No, that's not what I meant. Penthouse engines also have vertical spark plugs. But I think what you meant is that because the head of the engine is hemispherical, any non-direct combustion force will be directed down perfectly on the piston. So it's the shape of the head, not the position of the spark plug, that causes the combustion force to be directed onto the piston perfectly.

[anmesm58527]

well figure out what you mean, then post. cause to me you're saying that you could put the spark plug on the side and the hemi will direct all the power downwards? instead of saying "no you're wrong" say "that and". cause i know what im talking about. if you want to add onto what i say, go for it, but don't try to sound smart by refuting what someone that actually knows what the fuck they are talking about says. now im not so concieted to think im never wrong, but i know im not.

[philipp122]

Eh, I guess you're right. Wouldn't work too well with a spark plug on the side lol.

Right then. It's the spark plug position and shape of the cylinder head that directs the force perfectly downward :).

[yorrickhunt06]

Actually, your all wrong. A hemi of a given displacement will NOT necessarily make more power than any other engine with any other combustion chamber shape. In fact, the hemi combustion chamber is an outdated peice of poor engineering in the first place. Because the large surface area of the chamber is all exposed to the combustion flame, the head and piston crown are more prone to localised overheating, causing detonation.

[philipp122]

Well, hemis and penthouse designs both have their strongpoints and weakpoints, the Hemi does actually have the advantage of good torque because the cylinder head focuses the combuastion pretty well, but its downsides are what you said and the fact that you can't have multiple valves per cylinder.

[yorrickhunt06]

true enough. But the engine in the animation above here is still essentially from a 1950's tractor. In fact you wont find a racing engine anywhere outside the US and its satellite states that uses this combustion chamber

[philipp122]

Because it's a piece of crap lol. It completely disallows the use of multiple valves per cylinder, and it sucks fuel that doesn't even get fully used because the larger volume of the cylinder head means less compression in the engine.