Why Hemi?? - Dodge Challenger Forum: Challenger & SRT8 Forums
General Challenger Discussion This section contains general discussion about the Dodge Challenger. If it does not fit into a more specific area, it probably belongs in here. (Dodge Challenger General Discussion)

Reply
 
LinkBack Thread Tools Display Modes
#1 (permalink) Old 06-27-2010, 03:07 PM
Senior Member
 
Pythonman's Avatar
 
Join Date: Mar 2010
Posts: 499
Thanks: 0
Thanked 3 Times in 3 Posts
Feedback Score: 0 reviews
(Thread Starter)
Why Hemi??

I'm new to Mopars, having had a long time affair with mostly Fords and one '07 Mustang GT. I can appreciate the fine engines in both makes but I am interested in knowing how the Hemi engines in our R/Ts and SRT8s compare with Fords modular performance engines and Chevy's more performance oriented engines. What benefits are there in one make over the other and how do they compare reliability wise? Just curious cause I know there's lots of long time Mopar owners and I'd really like to hear what they have to say. Thanks!
Pythonman is offline  
Sponsored Links
Advertisement
 
#2 (permalink) Old 06-27-2010, 08:45 PM
Senior Member
 
TinCuda's Avatar
 
Join Date: Mar 2009
Location: Texas
Posts: 1,358
Thanks: 33
Thanked 294 Times in 170 Posts
Feedback Score: 0 reviews
Hope this helps...

The Hemi has been around for a long, long time in various forms. Early Triumph motorcycles used this design in 1937 and continued using it up until 1988. Chrysler borrowed ideas for their design from Weslake which built speed parts for Bonneville salt flat racers. Chrysler really utilized it best in automobiles in the early fifties and it's still the all time power king in racing. A drag racing blown hemi produces in excess of 6000 horsepower which is many times what anything else is capable of producing.

The hemi has four main advantages:

1) The spark plug(s) reside directly in the middle and top of the combustion chamber. This makes for a nice, even firing pattern. This is why Hemi engines have spark plug holes right in the middle of the valve covers. Other "wedge" engines like Chevy and Ford V-8's have their spark plugs off-center which is cheaper to build but less efficient.

2) Larger valve size. Draw a circle on a piece of paper. Now draw a line through the middle of it. Now draw two circles on ONE side of that line and you'll see how most ordinary V-8 heads are designed. To draw a Hemi, place one big cirle on one side of the line and another big circle on the other side of the line. Bigger valves mean more efficient and rapid airflow through the engine.

3) Larger combustion chamber surface area. The chamber is of the pentroof design (used by Ricardo in the 1910's) which means it's kinda funnel shaped. More area means more even heat transfer and distribution. More fuel and air can be crammed into the combustion chamber thus producing more power.

4) By placing the valves across from each other, the intake and exhaust flows across the combustion chamber. On a standard wedge head, they enter on one side, turn and cross and turn again to exit the cylinder. That's inefficient. The Hemi is a true flow-through design.

Today, there are numerous manufacturer's who make more efficient designs than the 2-valve Hemi. Most of the DOHC 4-valve designs will easily outflow a Hemi to a point. They have more valve area, however the size of the ports is usually very small increasing intake and exhaust velocity. That's great if you want maximum combustion efficiency but not great if your goal is to move massive amounts of fuel and air through the engine.

For today, the modern Dodge street Hemi is primarily a sales tool. The name, reputation and mystique alone will sell cars. It does produce great power & torque and is definitely an option worth considering.

The term Hemi which is short for Hemispherical simply means half sphere which is what the combustion chamber looks like, with one valve on each side.

1971 Plymouth 'Cuda 440-6
2000 Yamaha V-Max
2015 Chrysler 200 3.6 litre AWD
2008 Dodge Charger R/T Hemi
2011 Dodge Challenger SRT8 392 Hemi


Last edited by TinCuda; 06-27-2010 at 10:14 PM.
TinCuda is offline  
#3 (permalink) Old 06-27-2010, 09:27 PM
Senior Member
 
Join Date: Feb 2009
Location: North of Dallas
Posts: 6,573
Thanks: 219
Thanked 445 Times in 345 Posts
Feedback Score: 0 reviews
Plus, doesn't it tickle your fancy that not only do you have a v8 unlike most cars on the road, but you have a v8 that isn't like most v8's on the road, as well? It's almost a badge of honor to carry on the torch for a valvetrain and head configuration that set the v8 world on its ear in the 60/70's. It's not just built to be the most dirt simple and cheapest approach to get 2 valves in a cylinder head. It is "special" from the perspective that it is arguably the most elegant and sophisticated engineering approach to put 2 valves in a cylinder head, even if there were no tangible benefits in actual output. It is like the Ferrari of v8's, in a world where nearly any other v8 under the sun is built in a more "commoner" manner. I guess it is like "v8 royalty" in a nostalgic light.

http://www.challengertalk.com/forums/signaturepics/sigpic6929_4.gif

09 Challenger R/T automatic...4 tires, stick-on convex mirror, seats

It's not that I really needed 370 hp...but having 150+ hp riding shotgun at a moment's bidding w/o a 6000 rpm moonshot is what makes me feel like I'm in the right car for me. The roar of a v8 seals the deal!

The Google keyword is "ethanol-free gas". The truth is coming to light. Check out http://pure-gas.org/

Last edited by randycat99; 06-27-2010 at 09:30 PM.
randycat99 is offline  
#4 (permalink) Old 06-27-2010, 09:53 PM
Senior Member
 
Join Date: Apr 2009
Posts: 451
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
they could have built the new Hemi with some other type of design, but then they couldn't have called it a Hemi, right? Same reason they ressurected the Charger and Challenger names instead of the "Polara" or "Coronet", they just wouldn't sound as cool or sell as many.

09 R/T Hemi Orange 6 Speed, 27J, homemade ram air, Trinity, 91 CAI tune, drop in K+N, Hurst shifter, Thrush mufflers, resonator delete. M+H drag radials 275/45/18 and 18 front runners on spare rims.
13.27 @ 105.4 MPH
tony292 is offline  
#5 (permalink) Old 06-27-2010, 10:11 PM
mph
Senior Member
 
mph's Avatar
 
Join Date: Nov 2008
Location: State of confusion
Posts: 466
Thanks: 0
Thanked 3 Times in 2 Posts
Feedback Score: 0 reviews
1. "Bid Daddy" Don Garlits. If I'm not mistaken almost all of his wins came with Chrysler Hemi. He still advertises for Chysler, and has a strip version of the Challenger.
2."The King" Richard Petty. Most of his wins came in a Chrysler powered by a Hemi.
3. The Keith Black Hemi. Damn near a direct copy of the Chrysler Hemi block in aluminum. A butt load of NHRA funny cars and dragsters used that bock for quite some time, if they're not still using it.
4 The Chrysler Hemi is, to the best of my knowledge, the ONLY motor to be banned from NASCAR for a distinct advantage. Even though they didn't really invent it, and every manufacturer at the time had the same opportunity.

Need I say more?

I'd rather have a bottle in front of me than a frontal lobotomy.


Past Rides:
'67 Plymouth Fury III (State Cop Car)
2 '66 Dodge Coronets
'66 Dodge Charger
'67 Dodge Charger
'69 Plymouth GTX

Challenger Owners Club of North America

Last edited by mph; 06-27-2010 at 10:13 PM.
mph is offline  
#6 (permalink) Old 06-27-2010, 10:53 PM
Senior Member
 
Pythonman's Avatar
 
Join Date: Mar 2010
Posts: 499
Thanks: 0
Thanked 3 Times in 3 Posts
Feedback Score: 0 reviews
(Thread Starter)
Wow! Thanks for the cool Hemi history guys. That's cool stuff I just plain did not know. WHat I do know is the engine in my R/T get's pretty scary powerful at times compared to anything I've ever owned and she strongly reminds me of a hopped up 396 in a 67 Chevelle SS a neighbor of mine once had in pure grunt. Nice for a factory street ride!
Pythonman is offline  
#7 (permalink) Old 06-28-2010, 10:56 AM
Senior Member
 
09R/TPony's Avatar
 
Join Date: Jan 2010
Location: London,Ontario,Canada
Posts: 975
Thanks: 2
Thanked 138 Times in 82 Posts
Feedback Score: 0 reviews
Hemi Engine

Quote:
Originally Posted by Pythonman View Post
I'm new to Mopars, having had a long time affair with mostly Fords and one '07 Mustang GT. I can appreciate the fine engines in both makes but I am interested in knowing how the Hemi engines in our R/Ts and SRT8s compare with Fords modular performance engines and Chevy's more performance oriented engines. What benefits are there in one make over the other and how do they compare reliability wise? Just curious cause I know there's lots of long time Mopar owners and I'd really like to hear what they have to say. Thanks!
Check out the following link and attached PDF file for some additional information.

Howstuffworks "How HEMI Engines Work"
Attached Files
File Type: pdf The Hemi Engine.pdf (1.44 MB, 103 views)
09R/TPony is offline  
#8 (permalink) Old 06-28-2010, 12:40 PM
Super Moderator
 
Cuda340's Avatar
 
Join Date: Sep 2006
Location: southern New Jersey
Posts: 8,633
Thanks: 1
Thanked 795 Times in 526 Posts
Garage
Feedback Score: 0 reviews
Quote:
Originally Posted by mph View Post
1. "Bid Daddy" Don Garlits. If I'm not mistaken almost all of his wins came with Chrysler Hemi. He still advertises for Chysler, and has a strip version of the Challenger.
2."The King" Richard Petty. Most of his wins came in a Chrysler powered by a Hemi.
3. The Keith Black Hemi. Damn near a direct copy of the Chrysler Hemi block in aluminum. A butt load of NHRA funny cars and dragsters used that bock for quite some time, if they're not still using it.
4 The Chrysler Hemi is, to the best of my knowledge, the ONLY motor to be banned from NASCAR for a distinct advantage. Even though they didn't really invent it, and every manufacturer at the time had the same opportunity. Need I say more?

You forgot the Sox & Martin Pro Stock 'Cuda and Dick Landy Challenger of the late 60s early 70s.

Cuda340 is offline  
#9 (permalink) Old 06-28-2010, 03:41 PM
mph
Senior Member
 
mph's Avatar
 
Join Date: Nov 2008
Location: State of confusion
Posts: 466
Thanks: 0
Thanked 3 Times in 2 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by Cuda340 View Post
You forgot the Sox & Martin Pro Stock 'Cuda and Dick Landy Challenger of the late 60s early 70s.
Hey, I can't think, drink & type ALL at the same time. Now, drinking, drooling & typing I have a better shot at. Your ARE absolutely right though.
mph is offline  
#10 (permalink) Old 06-28-2010, 04:11 PM
Senior Member
 
Join Date: Sep 2008
Location: Minnesota on the lake
Posts: 630
Thanks: 2
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
One more thing, ALL of the NHRA funny cars and top fuel cars have hemi engines. It doesn't matter if they say Ford, Chevy, Toyota, or DODGE on them. They are all HEMI'S and have between 6000 and 7000 hp. Now, that's something to be proud of.

garylee is offline  
Sponsored Links
Advertisement
 
Reply

  Dodge Challenger Forum: Challenger & SRT8 Forums > General, Performance, and Technical > General Challenger Discussion

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Dodge Challenger Forum: Challenger & SRT8 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Hemi and Header Orange Challengers olskooljr Picture/Media/Art Post 122 09-07-2014 08:02 PM
Is My SXT Looked Down Upon??? challenger-dan General Challenger Discussion 343 04-14-2013 02:36 PM
What's Up With 392 Hemi Owners In Philly Area??? 6SPD4ME North-East 9 08-14-2012 04:58 PM
2010 Hemi Orange & Furious Fuchsia joined by New Hemi 6.1 LETSJET General Challenger Discussion 6 07-17-2012 12:44 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome