Normal Engine Compared To A Hemi?

ThoR_ · 06-02-2007, 12:58 AM

Hey guys.

Laugh if you will but ive been wondering for years and dont know so i figured it is time to find out. Whats the difference. Everyone goes on about 265 hemi`s and hemis in general aaww there so awsome and they kick ***. Whats the difference between them and a say a motor that would be a normal 265 or a Ford 250?

Whats the fuss? My old stepdad told me that hemis suck and are slow because they have no compression. So glad he`s gone. F%$&#% Nob.

So give it to me? (dont think dirty)

Night Runner · 06-02-2007, 01:21 AM

The true Hemi is the 426 HEMI which was not the first Hemi built, wedge etc. Hemi is a "Hemisphere" or "crossflow cylinder head" design. A internal-combustion engine in which the cylinder head's combustion chamber is of hemispherical form.

Every car you see in Top Fuel on NHRA is running a Hemi engine. The idle sounds tacky and they weigh a tonne aka " The Elephant Motor" but they sure can move. They were rated at a conservative 425hp & 490ft-lb of torque but dynos have shown otherwise, close to 500hp and 570lbs. It doesn't take much to make these engines extremely dangerous hp/torque wise. Comp Ratio was 10.25 to 1 and they were fitted with 2 x 4-bbl Carter AFB carbs. Steel crank, rods and aluminum pistons were all standard.

They were the king of the streets and even by today's standards, they are king of the roads of the classic cars. Though, a 440-6bbl or Magnum would hold it's own to the speed limit down the 1/4 mile and race track is where the Hemi was in a league of it's own, loves to rev and the sound it makes is second to none. They ruled NASCAR, NHRA and anything they were in. Big dollars now, a HEMI engine from 68-70 era will set you back $40,000 Australian dollars and combine that with a Plymouth 'Cuda and number matching cars with this combo have sold for 4 million US, yes, 4 million USD.

Hope that helps somewhat. In short, it's the Hemispherical heads.
Below is a cut away photo of a 426:

ThoR_ · 06-02-2007, 01:26 AM

cheers

Night Runner · 06-02-2007, 01:28 AM

You're welcome.

XR Martin · 06-02-2007, 04:10 AM

Most modern 4valve engines feature 'Hemi' combustion chambers, so its not exactly a unique feature any more.

4Vman · 06-02-2007, 08:09 AM

The 6 cyl chrysler motors aren't true Hemi's, as per the original 426 head design, they just use the name.

blackjack · 06-02-2007, 08:32 AM

Quote:

Most modern 4valve engines feature 'Hemi' combustion chambers, so its not exactly a unique feature any more.

Yeah but there not a "hemi" ;)

Wally · 06-02-2007, 09:18 AM

http://auto.howstuffworks.com/hemi.htm

Night Runner · 06-02-2007, 04:54 PM

Quote:

Originally Posted by XR6 Martin

Most modern 4valve engines feature 'Hemi' combustion chambers, so its not exactly a unique feature any more.

Yes, but if Mopar weren't around there would be none. It's basically the same as the first engine built. Others copied the design and the auto industry moved on. It's not unique but to come up with that design some 40+ years ago is pure genius. The Hemi engine deserves respect, most car enthusiasts would agree.

_2:

XR Martin · 06-02-2007, 06:03 PM

I dont think they invented the Hemispherical combustion chamber, there were 4 valve engines well before the famous 'Hemi' engines came along.

Night Runner · 06-02-2007, 07:01 PM

The cars you speak of the 3 liter Peugeot Grand Prix car & The BMW 328? had angled valves and overhead camshafts. This was not a hemispherical chamber, they had four or six valves in what's known as a pent-roof chamber. Most used either or as it was the norm for racing engines worldwide.

Some of the differences between the earlier Hemis were the valve train; dual overhead camshafts, a single overhead camshaft, or push rods. Chrysler used push rods and they worked extremely well. The original Chrysler "Hemis" were called "The Double Rocker". It wasn't until the 426 that "Hemi" became standard. And as I said, the HEMI is now a registered trademark of Daimler-Chrysler.

There were a few to claim it and as far as I know, no one really "claimed" the Hemi engine as there own. What I can tell you is Chrysler invented mass produced hemispherical head engines that were second to none, built there way which set the bench mark on big block warfare was they easily rained supreme. The ole motto for the era was win on Sunday, sell on Monday.

Richmalbill · 06-02-2007, 09:43 PM

Quote:

Originally Posted by NZ-TS50

The cars you speak of the 3 liter Peugeot Grand Prix car & The BMW 328? had angled valves and overhead camshafts. This was not a hemispherical chamber, they had four or six valves in what's known as a pent-roof chamber. Most used either or as it was the norm for racing engines worldwide.

Some of the differences between the earlier Hemis were the valve train; dual overhead camshafts, a single overhead camshaft, or push rods. Chrysler used push rods and they worked extremely well. The original Chrysler "Hemis" were called "The Double Rocker". It wasn't until the 426 that "Hemi" became standard. And as I said, the HEMI is now a registered trademark of Daimler-Chrysler.

There were a few to claim it and as far as I know, no one really "claimed" the Hemi engine as there own. What I can tell you is Chrysler invented mass produced hemispherical head engines that were second to none, built there way which set the bench mark on big block warfare was they easily rained supreme. The ole motto for the era was win on Sunday, sell on Monday.

Actually Chrysler were pretty late on the Hemi scene. Riley were a particularly accomplised exponent of the pushrod hemi engine in both twin cam four cylinder and triple-cam V8 form. Way ahead of their time.

The Jaguar XK engine also pre-dates the Chrysler Hemi by a fair margin and was a DOHC Hemi.

Night Runner · 06-02-2007, 10:40 PM

Quote:

Originally Posted by Richmalbill

Actually Chrysler were pretty late on the Hemi scene. Riley were a particularly accomplised exponent of the pushrod hemi engine in both twin cam four cylinder and triple-cam V8 form. Way ahead of their time.

The Jaguar XK engine also pre-dates the Chrysler Hemi by a fair margin and was a DOHC Hemi.

True to some degree but we are talking the 426 Hemi engines, not 4 cylinders or triple cam setups. Chrysler were making Hemi style engines for aircraft before they were dropping them between shock towers, 1950 was when they started using them in consumer cars. The XK was 4.2L producing a lowly 265hp?, some 160hp (at the least) less than the elephant engine. No one came close, far from it, in producing the power and torque that the famous 426 Hemi did and does even to this day with crate 528ci engines available and modern aluminum 426 Hemi blocks still for sale from Ma Mopar.

The XK heads were a Hemi design yes, but you aint seen heads till you've seen 426 Heads which were not identical (far from it) to the XK style chambers. The 426 was double the size of anything close to being classed in the same league.

_2:

blackjack · 06-02-2007, 11:31 PM

Which is why I said the others are not classed as Hemi as its a registered trademark by Chrysler.

The hemispherical combustion chamber has been around since the 1930's if not earlier! So it’s not really a new thing.

Like others have mentioned before, they have pent roof combustion chambers (again couple of decades old) which are better then the hemi style chambers as the offer a more direct path for the air fuel mixture to enter the chamber.

In saying this though, i have in a old street machine mag, SVO making a hemi style head for the 429 big block. I'll have to find that...

Night Runner · 06-02-2007, 11:37 PM

I'm not saying they were the first to invent this style head, no one knows for sure who did, IMO it was the entire motoring world threw in it's 2c worth.

The poster and topic at hand is about the powerfulest Hemi of them all - The 426ci HEMI.
Which took HEMI "styled" engines to a totally new level. As I said, all engines in Top fuel are based on the Chrysler Hemi, not the pimp-squeak BMW or 265hp Jaguar engines of yesteryear. Yes they all help evolve the Hemi style engine but tyres and steering wheels have also come along way.

I'm sure the Dodge Brothers also gave Uncle Henry his first engines? Ford, born a Mopar.

: Na, I think that's true to some degree though....have to read a few books to find out for sure.

Perana · 06-02-2007, 11:40 PM

3+ Valve engines are generally known as a pent-roof design not Hemi

The Hemi design was first used in 1905! By a belgian car maker. Quite a number of manufacturers (Daimler, Riley are 2) used it well before Chrysler ever did. Jaguar had it avaliable to the public 10 years before Chrysler! The Jag engines were far from slow when tuned a bit too, same design heads were used on the V12 Jag engine too.. 600HP wasnt difficult with those...

Night Runner · 06-02-2007, 11:43 PM

Yes, the design but as I said, comparing those heads/engine to the 426 is like the Sydney harbour bridge to a cardboard box - No comparison. The Dodge Brothers I'm sure were also part of that early 1900's. group too.

XR Martin · 07-02-2007, 01:19 AM

Quote:

Originally Posted by NZ-TS50

True to some degree but we are talking the 426 Hemi engines, not 4 cylinders or triple cam setups. Chrysler were making Hemi style engines for aircraft before they were dropping them between shock towers, 1950 was when they started using them in consumer cars. The XK was 4.2L producing a lowly 265hp?, some 160hp (at the least) less than the elephant engine. No one came close, far from it, in producing the power and torque that the famous 426 Hemi did and does even to this day with crate 528ci engines available and modern aluminum 426 Hemi blocks still for sale from Ma Mopar.

_2:

Read up on the Ford 427 Cammer engine, 650hp from the factory. Banned in NASCAR before it could go head to head with the 426 Hemi.

Night Runner · 07-02-2007, 01:50 AM

Quote:

Originally Posted by XR6 Martin

Read up on the Ford 427 Cammer engine, 650hp from the factory. Banned in NASCAR before it could go head to head with the 426 Hemi.

Yupe, I have heard of this engine before, great sounding engine on paper, would have been a good show down. One thing you're forgetting, Ford went out of their way to build this engine as a Hemi competitor, Chrysler knew nothing of this and were building there engines for street cars not for all our brawls ie: Ford CEOs vs Mopar CEOs.

The Hemi's they built for track and strip cars Superstock Coronets (which were available to the public) had upwards of 650hp. If Ford had made these SOHC engines for consumers that would have been an engine, but all they did was spend some time trying to find away to beat the Hemi and the Hemi still had cards up it's sleeve and they weren't even trying.

Night Runner · 07-02-2007, 02:04 AM

If we're talking fastest factory cars, the HEMI was the fastest muscle car with a 10.5 second 1/4 mile @ 130mph done in the 68 Barracuda SS & 68 Dart SS respectively, both stock and both production cars. The only car to top that to date is the 2007 Bugatti Veyron by a mere 0.03 seconds.

XR Martin · 07-02-2007, 02:10 AM

Quote:

Originally Posted by NZ-TS50

Yupe, I have heard of this engine before, great sounding engine on paper, would have been a good show down. One thing you're forgetting, Ford went out of their way to build this engine as a Hemi competitor, Chrysler knew nothing of this and were building there engines for street cars not for all our brawls ie: Ford CEOs vs Mopar CEOs.

The Hemi's they built for track and strip cars Superstock Coronets (which were available to the public) had upwards of 650hp. If Ford had made these SOHC engines for consumers that would have been an engine, but all they did was spend some time trying to find away to beat the Hemi and the Hemi still had cards up it's sleeve and they weren't even trying.

The engine was available to consumers, you could buy it over the counter of your local Ford dealer.

There was also the Ford Fairlane Thunderbolt, 550hp 427ci, which ran 11sec 1/4s from the factory in the early 60s.

XR Martin · 07-02-2007, 02:17 AM

Quote:

Originally Posted by NZ-TS50

If we're talking fastest factory cars, the HEMI was the fastest muscle car with a 10.5 second 1/4 mile @ 130mph done in the 68 Barracuda SS & 68 Dart SS respectively, both stock and both production cars. The only car to top that to date is the 2007 Bugatti Veyron by a mere 0.03 seconds.

A '69 ZL1 Corvette was just as fast as the Chryslers.

Also apparently the Veyron has run a 10.2, and a 06 Z07 Corvette has run a 10.85.

Night Runner · 07-02-2007, 02:30 AM

Quote:

Originally Posted by XR6 Martin

A '69 ZL1 Corvette was just as fast as the Chryslers.

Also apparently the Veyron has run a 10.2, and a 06 Z07 Corvette has run a 10.85.

The 69 ZL1 Camaro was well of the pace mate, 12.76 @ 107. The ZL1 Corvette (427) ran a 10.89. The 2006 Corvette's time is down at 11.5 @ 127.1 Sorry, that was a typo, it was suppose to read 0.30 which of course would equal your posts 10.2 (10.5 - 0.30 = 10.2).

Quote:

Originally Posted by XR6 Martin

The engine was available to consumers, you could buy it over the counter of your local Ford dealer.

There was also the Ford Fairlane Thunderbolt, 550hp 427ci, which ran 11sec 1/4s from the factory in the early 60s.

From the Ford dealer, of course because they did build enough to legalise it (homolgate ?sp) the car.
Right you are. Yupe, the Fairlane ran 11.76, so it's in the 11s....but 11 seconds and 11.76 is a big distance.

Like yourself, I could argue the facts all day long, I guess which ever way you look at it, (you're obviously a non-Mopar guy, I am) all these cars, Ford, Mopar or Chev, V8 powered are all marvels, drag racers will say 0.10 second is a mile but they're all close and all powerful and all worth a pretty penny.

To each his own.

XR Martin · 07-02-2007, 02:39 AM

10.85 from a Z06 C6 Vette ;)

http://forums.corvetteforum.com/show....php?t=1541575

Steffo · 07-02-2007, 02:49 AM

Quote:

Originally Posted by XR6 Martin

10.85 from a Z06 C6 Vette ;)

http://forums.corvetteforum.com/show....php?t=1541575

He's right though, standard the C6 Z06 is an 11.5. That thing is on aftermarket tyres. That the standard ones are so bad is no one's fault by Chevy's.

Quote:

Originally Posted by XR6 Martin

Also apparently the Veyron has run a 10.2

Wheels December 2005 has the Veyron listed as doing 9.9 @ 225km/h for the quarter. And the Guiness Book of Records, if I'm not mistaken, has the Veyron listed doing 9.8 seconds.

Night Runner · 07-02-2007, 02:49 AM

Quote:

Originally Posted by XR6 Martin

10.85 from a Z06 C6 Vette ;)

http://forums.corvetteforum.com/show....php?t=1541575

That's without factory tires mate. Also, the figures I have, have been taken from the following sources: American Hot Rod, Car & Driver, Motor Trend, Road & Track, Automobile, Popular Hot Rodding, Wheels.....the list goes on, not from the owner of the car. For all we know he could have some minor mods and not tell anyone....after-all, he is the hero.

Still slower than the Hemis albeit with 40 years tech under it's belt. ;)

Night Runner · 07-02-2007, 02:51 AM

Quote:

Originally Posted by Steffo

Wheels December 2005 has the Veyron listed as doing 9.9 @ 225km/h for the quarter. And the Guiness Book of Records, if I'm not mistaken, has the Veyron listed doing 9.8 seconds.

Really, WHOA!! That is fast, but, doesn't mean much for this argument as it was already number one with a 10.2.

:eclipsee_