Stoopid Engine Question -- Newbie

[italianguy63]

Guys, I am new to the Mopar performace world. I have always been a Chevy guy engine wise. I have built quite a few "smallblocks." I have always respected the Mopar "Hemi" but could never afford to own one! They are not near as easy or cheap to build as a Chevy. Anyway, that being said-- I am "old school" and am aware of the 340 and 360 Hemi. My question is: are the 5.7 and the 6.1 based on the old 340 and 360 or are they completely new animals?

MC

[kevenj]

Originally Posted by italianguy63

Guys, I am new to the Mopar performace world. I have always been a Chevy guy engine wise. I have built quite a few "smallblocks." I have always respected the Mopar "Hemi" but could never afford to own one! They are not near as easy or cheap to build as a Chevy. Anyway, that being said-- I am "old school" and am aware of the 340 and 360 Hemi. My question is: are the 5.7 and the 6.1 based on the old 340 and 360 or are they completely new animals?

MC

Neither the 340 nor the 360 were Hemi's. They were in the same family as the 318 that was the Chrysler workhorse for many, many years.

The "old" hemi's (and I'm SURE I'm leaving something out....) were 354, 392 in the 50's - - and then the famous 426. There was a 426 wedge head engine in the 60's too, adding to the confusion.

I "THINK" there was a 331 (?) hemi before the 354...not sure. And I know that the DeSoto division had a 341 hemi, because my buddy in high school had a 1957 DeSoto Fireflite with a 341 hemi and the push-button controlled 727 torqueflite. (And fins nearly as tall as the roof!)....I remember helping him pull the heads do have a valve job done.....those old cast iron hemi heads were HEAVY !!

The "NEW" hemis are completely different animals, yes.

[italianguy63]

Cool-- thanks! I did not know the 340 and 360 weren't hemi's-- SEE!

Thanks for the info.

[Mr. iNCREDIBLE]

5.7L 347.8 CI

6.1L 370 CI


all new animals.. not even related to the hemi's of the past... and the new "hemi" aren't true Hemis.. they are "Semi-Hemi's"

I know, I know now I'm shunned...

[italianguy63]

I understand-- I was just wondering if the new engines were just knock offs of the old block castings (for example the GM 305 is just an old smallblock around since the late 50's). I was just wondering where the new Mopar "semi" hemi came from. It is cool if they pumped R&D money into totally new engines....

MC

[phunter1]

The original Chrysler 300 in 1955 had a 331 cu in hemi rated at 300 hp. There were also several smaller hemi's in Dodges and DeSoto's. The smallest was 241 cu in, used by Dodge in 1953 and 1954.
The 426 hemi was not related to the earlier hemi's, but was derived from the "B" block 426 Wedge motor.
I suspect, but don't know for sure, that the current hemi is derived from the small block "A" series wedge motors. Perhaps someone could shed some light on this.

Phil

[kevenj]

Originally Posted by phunter1

The original Chrysler 300 in 1955 had a 331 cu in hemi rated at 300 hp. There were also several smaller hemi's in Dodges and DeSoto's. The smallest was 241 cu in, used by Dodge in 1953 and 1954.
The 426 hemi was not related to the earlier hemi's, but was derived from the "B" block 426 Wedge motor.
I suspect, but don't know for sure, that the current hemi is derived from the small block "A" series wedge motors. Perhaps someone could shed some light on this.

Phil

I thought there was a 331 but I wasn't sure. Didn't know about the smaller ones at all.

The new 5.7 & 6.1 are completely different from anything in the past. They are not derived from the 318/340/360 in any way. Here's a good write up on the "new" hemi:
Chrysler Hemi 5.7 Liter 345ci – Overview, Stats – Popular Hot Rodding

[srt8danno]

Here is some further reading on the history of the hemi and some of the details associated with it.

Chrysler Hemi engine - Wikipedia, the free encyclopedia