YACT - Ask all stupid newbie car questions here...

[Placer14]

I'll start

I really haven't heard all the much about the hemi engine until recently on here and then saw one of those Dodge commercials talking about it. I heard from some of the other members that it's been around for a while, just not really mentioned. Advantages, disadvantages? What makes/models/classes are they generally associated with?

 

[ChinamanatNCSU]

I'll ask an even newbier question-

what's a hemi engine?

 

[Ryan]

Search! It has already been discussed

 

[PsychoAndy]

The Hemi was used back in the late 60's to early 70's in Mopar muscle car offerings. Hemispherical combustion chamber with 2 spark plugs. Pretty inovative design IMHO. Performance was pretty sweet. I think a bunch of them put out 1 HP for every CID (For refrence: a 1996 350 CID chevy is rated at 225 HP). IIRC, new emissions standards made the Hemi obsolete.

Cool engine though.

-PAB

EDIT: Ok, I'm wrong so I'm gonna concede the point. Roger's old and has been around, so he knows this stuff. Hemi came out in the 50's.

 

They actually came out in the fifties, not the sixties as most people think.

 

[PsychoAndy]

Originally posted by: Roger
They actually came out in the fifties, not the sixties as most people think.

Yay for correctness. Its amazing how geocities sites warp your mind.

-PAB

 

[jemcam]

And they only had one spark plug per cylinder, not two. Yes, those were leading edge technology engines in the mid 50's.

Edit: Chrysler reviving the hemi is really just a marketing ploy. There are lots of better ways to make an engine produce more hp. Even Harley Davidson had hemi engines in their shovelhead motors, which came into their own during the sixties and were produced until the early 80's. If Harley abandoned the hemi idea in the 80's, you know it's not all that great. And before anyone flames me for talking trash about Harley's, I'm a big Harley fan & rider and have been for years.

 

[PsychoAndy]

Originally posted by: jemcam
And they only had one spark plug per cylinder, not two. Yes, those were leading edge technology engines in the mid 50's.

Am I carrying stuff over from the new one? I vaguely remember hearing about 2 per from somewhere.

-PAB

 

[jemcam]

Originally posted by: PsychoAndy

Originally posted by: jemcam
And they only had one spark plug per cylinder, not two. Yes, those were leading edge technology engines in the mid 50's.

Am I carrying stuff over from the new one? I vaguely remember hearing about 2 per from somewhere.

-PAB

Could be, I haven't read much about the new hemi. I do know for a fact that the original Chrysler hemi's only had one sparkplug per cylinder.

 

[Placer14]

So....forgive my ignorance. Am i correct to believe that the newer V/inline type combustion engines are superior to hemi type engines? And does anyone know if improvements have been put in the new hemi engines?

Am I talking about apples and oranges?

 

[PsychoAndy]

Originally posted by: Placer14
So....forgive my ignorance. Am i correct to believe that the newer V/inline type combustion engines are superior to hemi type engines? And does anyone know if improvements have been put in the new hemi engines?

Am I talking about apples and oranges?

I would say: depends on application.

I'm trying to find the autoweek article on it. Emissions did get better in the new hemi. Had to meet new regs.

-PAB

 

[jemcam]

Originally posted by: Placer14
So....forgive my ignorance. Am i correct to believe that the newer V/inline type combustion engines are superior to hemi type engines? And does anyone know if improvements have been put in the new hemi engines?

Am I talking about apples and oranges?

Hemi engines in the 50's and 60's were still v8's. It's the actual combustion chamber in the head that was hemisperical. When the piston went up to top dead center (TDC), the combustion chamber was hemispherical. Back then, they believed that would provide the best combustion environment. Since then, other engine manufacturers, (like GM with the Vortex motors) have come up with swirl designs, multiple sparkplugs, multi-valves etc. I doubt that the new hemi is anything close to the old ones, they just revived the name.

 

[Vette73]

Hemi only has one plug. And the new hemi is a full redesign. i think car and driver or hot rod had both of the insides and they are similar, but the new one is way more complex as it should be.
But it is more of a ad thing then a working thing.

Chevy/GMC still make the best all round trucks.

 

[Quixfire]

Some of the more recent race Hemi engines, like Kieth Black & Aries, use one to four spark plugs per cylinder. But only one plug was used in a production engine. And don't forget the Fords attemt at a Hemi engine, 429 Boss.

 

[Placer14]

Okay, that explains a little better. Before, when I thought "hemi" design, I'm thinking a huge half cirlce in the center and cylinders all combust in the one hemisphere. But the other way seems to make more sense. Can anyone give me decent sites/articles (that would otherwise be hard to find in a search) that they might know of that compares the different technologies or articles that might explain the different types of combustion engines better to this newb.

if not, I'll just search for more info tonight. Thanks again.

 

[jemcam]

Originally posted by: Placer14
Okay, that explains a little better. Before, when I thought "hemi" design, I'm thinking a huge half cirlce in the center and cylinders all combust in the one hemisphere. But the other way seems to make more sense. Can anyone give me decent sites/articles (that would otherwise be hard to find in a search) that they might know of that compares the different technologies or articles that might explain the different types of combustion engines better to this newb.

if not, I'll just search for more info tonight. Thanks again.

No sites, but if you're interested in this type of thing, look up wankel, diesel, rotary, and miller engines as well as 2 stroke and 4 stroke engines. All different types of engines, but they all require 3 things: spark, fuel, and air. The different types of motors that I listed just combust or process the 3 requirements in different ways.

 

[PsychoAndy]

Ok, here we go. Article on the new hemi and 2 plugs. I guess I saw 2 and carried it over to the old ones as well.

autoweek

-PAB

 

[Zenmervolt]

Originally posted by: PsychoAndy
The Hemi was used back in the late 60's to early 70's in Mopar muscle car offerings. Hemispherical combustion chamber with 2 spark plugs. Pretty inovative design IMHO. Performance was pretty sweet. I think a bunch of them put out 1 HP for every CID (For refrence: a 1996 350 CID chevy is rated at 225 HP). IIRC, new emissions standards made the Hemi obsolete.

The Hemi was also innovative when Porsche designed and built the Carrera 4 Cam engine in 1955 with a hemi-head. Porsche's design did have two spark plugs per cylinder though.

ZV

 

[LAUST]

I don't think todays hemi and the great hemi of the Muscle car era can even be compared... BB vs Small block, FI vs Carb, Compression ratio's, Torque curve... it's got the BASIC CHAMBER desighn and I bet it will end up a great motor and thank gawd they replaced the 360, but I think it should be allowed to build it's reputation and not be a puppet of the one of old.

 

[LAUST]

Originally posted by: Quixfire
Some of the more recent race Hemi engines, like Kieth Black & Aries, use one to four spark plugs per cylinder. But only one plug was used in a production engine. And don't forget the Fords attemt at a Hemi engine, 429 Boss.

Ford built a 427 Hemi-headed SOHC motor also, but NASCAR didn't allow it so along came the "semi-Hemi" head 429

 

[Quixfire]

Originally posted by: LAUST

Originally posted by: Quixfire
Some of the more recent race Hemi engines, like Kieth Black & Aries, use one to four spark plugs per cylinder. But only one plug was used in a production engine. And don't forget the Fords attemt at a Hemi engine, 429 Boss.

Ford built a 427 Hemi-headed SOHC motor also, but NASCAR didn't allow it so along came the "semi-Hemi" head 429

Your right, but Ford never put that engine in true production vehicle. The only cars were the Fairlane Thunderbolt and the Comet A/FX and less than fifty were built of each. And that is the reason NASCAR wouldn't let them run the car, not the engine it's self.

 

[LAUST]

Okay my turn to ask a question.... Whats the deal with the Coffie can exhaust tips? is that some sort of pulse detonation to make those little things go faster??

 

[Placer14]

Originally posted by: LAUST
Okay my turn to ask a question.... Whats the deal with the Coffie can exhaust tips? is that some sort of pulse detonation to make those little things go faster??

Exqueeze me...i baking powder??

I have another somewhat general question. I've always been facinated with how things work. Cars included. But with their precision and complexity, i've always been intimidated to work on them. Any suggestions as far as how you start working on/learning about cars and what questions I should ask, things to do so I can avoid commonly made mistakes, etc and start off on the right foot? Thanks again.

I used to own an '85 Camaro Coupe that would've been fun to work on, but my sister totaled it. what are good (read: cheap) cars to work on for learning?

 

[Iron Woode]

Originally posted by: Quixfire

Originally posted by: LAUST

Originally posted by: Quixfire
Some of the more recent race Hemi engines, like Kieth Black & Aries, use one to four spark plugs per cylinder. But only one plug was used in a production engine. And don't forget the Fords attemt at a Hemi engine, 429 Boss.

Ford built a 427 Hemi-headed SOHC motor also, but NASCAR didn't allow it so along came the "semi-Hemi" head 429

Your right, but Ford never put that engine in true production vehicle. The only cars were the Fairlane Thunderbolt and the Comet A/FX and less than fifty were built of each. And that is the reason NASCAR wouldn't let them run the car, not the engine it's self.

Time to clear up some miscomceptions here:

1. Thunderbolts only came with 425hp 427 engines. No sohc ever in any publicly sold example.

2. Sohc 427 never made it into any production vehicle.

3. Boss 429 was not a real hemi either. At best it was a "sort of" hemi like the old Mopar poly smallblocks of the 50's and early 60's.

4. the hemi combustion chamber is the most efficient one ever made.

5. there are other combustion chamber designs: wedge, squish, bathtub, etc...

6. Nascar wouldn't allow 427 sohc because Ford must sell 500 minumum in a production car first. Mopar tried a sneak approach with the 426 hemi, which won 1st 2nd 3rd and 5th in the 1964 Daytona 500. Claiming that the 426 wedge was available and that therefore the hemi was legal too because it was based on that engine. It didn't fly and mopar was out of the 65 season.

7. the new hemi should be a great engine, esp for engine swaps.

What was the fastest, baddest musclecar to ever come out of Detroit?

The 1968 Hemi Dart and Baracuda. Not legal for highway use because of safety equippment missing. Only 50 of each made. They came with only front seats, stock type tires and rims, single exhaust and a black gel-coat body. Put on real tires and slicks, open headders and run the factory tuning and you get low 11's to high 10's in the quarter mile. Put a real tuning on there and things get out of hand in a hurry. The engine is not stock 425 hp version but a factory rated 550hp version. It probably made more. It was a full race engine.

 

[Placer14]

Alright, more questions...

Is a fuel filter change generally covered in the tuneup, or does it vary from shop to shop. What are some things that should be changed reguarlay other than Oil every 3000 mi or 3 mo.