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Hemi? more characters here

How are today’s youth any different than when we were young folks? Same as it ever was. We (society) are richer as a whole than we were in the 1960s, and richer then than in the 1930s. I’m sure our parent’s generation said the same thing about us.

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As already stated, today’s youth are no different than we were at that age. If anyone tried to lecture me/us about how we should not drive a muscle car, would we have listened?

If your son has the Hemi in his head just direct him back to about 1904… when the concept began.

You can also direct his attention to the many WWII aircraft engines that employed this feature…along with fuel injection and 4 valves per cylinder… in the 30’s n 40’s…not exactly “cutting edge” tech…

There is not much new about this combustion chamber shape… and in this day and age of proper fueling and scavenging, not to mention forced induction… the Hemi Hype…of today is just that… it was NOT hype back in the day, not at all. But today with full control of almost every aspect of internal combustion the “ Hemi “ should not induce fear or worship… it had its place and it is a valid concept and does have advantages, but we have moved past this today… waaay past this.

Back in the days of carbs and iffy fuel types and lead and points and condensers… the Hemi was on top of the HP heap because of how it helped combustion… since we now can much more finely control combustion with fuel and or direct or forced induction coupled with computerized ignition events etc… the hemi doesnt have the gain factor that it did in the days of the Venturi… and points, condensers, caps, rotors, wires… Which are all another way of describing how to delay an ignition/ combustion event at the exact time you wanted it to occur…

So if some recent commercial is making someone froth at the mouth about a Hemi combustion chamber… the makers of said commercial are just using that time honored method of Bamboozlement…

Take two parts fiction add one or 1.5 parts truth and you come up with an ideal lie and an even better way to confuse people who know just enough to get confused.

That is what the word “hemi” means today. It meant something at one time… and today? Not so much… haha

Thats my take

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Well, my father–who lived during the worst of The Great Depression–would not have said it about me. Perhaps I was different than some others of my generation, but I think that most people whose parents suffered during The Great Depression were given financial lessons similar to the ones that I received from my parents.

Just like with any other type of lesson, some pay attention and internalize the message, and others ignore the content.
:thinking:

The only Chrysler 300 with a 392 were the 57 and 58.

Te 55 had a 331 and the 56 had a 354. After 58 all the later series had wedge engines.

The 6.4 L engine used in the late model cars and trucks has a 391 CID but is advertised as 392 CID as a commemorative reference to the first generation Hemi engine.

Still a little bit of truth with the Hemi . but the name itself is a misnomer. The firet series Hemi 1951-58 and the second series which started in 64 had truly hemispherical combustion chambers and really made the most top end power for their displacement of any mass produced American V8s. That was because the shape allowed larger valves for the same cylinder diameter and the intake valves being tilted toward the carb and the exhaust valves being tilted toward the exhaust manifold gave better flow characteristics. The new Hemi does not have a hemispherical combustion chamber even though it still has the crossflow heads.It looks more like a tent.

All that said, the latest Hemi variant always seems to be the most powerful American engine on the street.

All of Chryslerrs hemi engines have pushrods and two rocker shafts on each heads.
Ford has moved on to dual overhead cams and 4 valves per cylinder and if they ever extend that to the same displacement as the hemi should make more power.
Chevrolet has done an amazing job of developing the small block through many generations of improvements have developed lighter cheaper and more compact engines that make almost identical power with the aid of superior engine management technology.

By the way overhead cams and cross flow heads have been banned fron Nascar since 1957 so only Chevy races an engine that bears any resemblance to what they sell/

I knew that, more or less about the early Hemi, Dodge D500s had a smaller displacement ‘RedRam’ Hemi. I thought the 392 was still used in 1959, but from what you say it must have been replaced by the ‘B’ wedge engines,

Yes, I should have indicated I was talking about the letter cars.

Being off 1 cu in in displacement is nowhere near as bad as the 366/402 Chevelles that were both marketed as 396s.

Not for a long time. Chevy hasn’t raced a true wedge, or inline valve cylinder head since the 1990s.

Chevy NASCAR engines are best described as semi hemi engines much like the current Hemi. Like the old big block Chevy and the Hemi, the valves are not inline like all small blocks have been and currently are. Same for Ford and Toyota NASCAR V8s. Like the Hemi, the intake is canted towards the intake port and the exhaust is canted towards the exhaust port.

My information was from 2011, it mandated a wedge shaped combustion chamber and all the valves operating in a single plane. I was not aware that anything had changed enginewise.

When NASCAR was first form the cars were essential stock, some were actual street legal and driven to the track. Now they are pure race cars with stickers to tell them apart.
I would like to see, at the end of the season, the Top 20 drivers race with showroom stock (with roll cages and other safety gear) versions of their NASCAR car. That would a hoot.

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Since the car’s ultimate performance is the result of a combination of multiple factors, buying a car based solely on the engine is pretty silly so yes, he’s becoming a victim of marketing hype.

But logic isn’t going to win this argument so if he’s got the cash, you may as well smile and wish him well.
And if he get’s the Performance version, the costs of insurance, premium gas, maintenance and speeding tickets will help him quickly and permanently “cure that itch”.

Ford’s NASCA efforts were based off the Boss 302 engine for years from the late 60’s onward. The Boss smallblock engines did not have inline valves. The Chevy SB2 head that was used starting in 1998 did not have inline valves and the Toyota V8 that showed up around 2007 never had them.

Not sure where the 2011 rules info that mandated inline valves came from, but it is not correct.

It came from a 2011 Popular Mechanics article about Nascar engines but is was far from the only source I had read it from. If it is misinformation, it has been widely disseminated.

It very much is. A Chevy SB2.2 NASCAR cylinder head. A revision of the 1998 head. Notice the canted valve spring seats indicating the valve angles.

Ford’s FR9 head used starting from 2009. Note the canted valve spring seats like the Chevy.

Dodge’s 2009 NASCAR head. Same thing, canted valves.

I found your 2011 Popular Mechanics article… This is the quote:

“Nascar engines must use a carburetor, pushrods, two valves per cylinder and a wedge-shaped combustion chamber—that’s right, no hemis allowed.”

Doesn’t say no inline valves, just no hemispherical combustion chambers.

I can’t really discern angled valves on the Ford or Dodge but they seem pretty evident on the Chevy.

Further down in the PM article under (1) Valvetrain it says
" Nascar engines use older less efficent wedge shaped combustion chambers with the intak and exhaust valvers in a single plane."

I am not claiming that the above information is correct, just explaining where I got the idea that splayed valves were not allowed. Can’t figure out why they banned the New Hemi, it certainly did not have a hemispherical combustion chamber ?

Did they hav \e a limit on the degree the valves could be canted?

NASCAR did not ban the new Hemi. The new Hemi appeared 4 years after Dodge re-entered NASCAR. You could more easily argue that the new Hemi was based on the NASCAR engine rather than the other way around.

Dodge left NASCAR in 2012. The engine they used was a clean sheet much like the Toyota, Ford and GM engines.

My daughter has a late model Sub Lime Green Challenger R/T with a Hemi and it’s one heck of a beast to drive. I’m surprised she threw the keys at me and said have at it. Pricy to fix too. A burnt out headlight was 600 bucks.

I think the modern Hemis are more closely related to the 318 Polyspherical engines than a true Hemi. That’s why the slightly derogatory “Semi Hemi” name attached to them. Myself? I say if he wants one go for it.

New ‘hemi’ is better in every way for a street car than the old HEMI.