'Splain this to me, Lucy.

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Captainkirk

Captainkirk

Old School Mopar Warrior
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OK, just got done decoding my '72 Duster 340 fender ID tag. Everything matches from what I can see, except one thing...the bottom row, far left set of digits is "E55", which decodes as "340 cid, 4 barrel V8 275 HP"
Now, I was always under the impression that the '72 motors were 8.5:1 compression, 240 HP from the factory according to all the info I've found to date. Was there some option to install a higher HP motor in these cars, or is the decoder program wrong?
 
Nope, E55 was the 340 engine code used for many years even though the compression ratio and power output changed. Also there was a change from gross to net power ratings in there too.
 
Just to clarify- keep in mind that not all '72s were the low-compression motors. Early year '72 still had the 10.5 forged crank engines and phased into the 9.5 versions later in the production run. To confirm it is the late motor, check your balancer- it will have a cast-in relief with the words "for cast crank 340 use only" or similar statement.
 
Like this:
s-l640.jpg
 
Professor Fate said:
Just to clarify- keep in mind that not all '72s were the low-compression motors. Early year '72 still had the 10.5 forged crank engines and phased into the 9.5 versions later in the production run. To confirm it is the late motor, check your balancer- it will have a cast-in relief with the words "for cast crank 340 use only" or similar statement.
Click to expand...
Don't have the original motor. Building a '72 motor with 10:1's and a forged crank over the winter.
 
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As stated above E55 denoted the 340 cu. in. motor. Had nothing to do with horsepower. Even the AAR and T/A were E55 and their hp rating was 290.
 
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Professor Fate said:
Just to clarify- keep in mind that not all '72s were the low-compression motors. Early year '72 still had the 10.5 forged crank engines and phased into the 9.5 versions later in the production run. To confirm it is the late motor, check your balancer- it will have a cast-in relief with the words "for cast crank 340 use only" or similar statement.
Click to expand...


THIS^^^^^^^^^^ I had one of those in a 72 Demon and absolutely screwed that car and myself.

Could I go back to 1984 the one thing (well two things...I would have quit drinking then) I would change is not laying a FINGER on that car. I was the second owner, had all the paper work and just blew it.

Makes me sick when I think back at all the cool cars my brother, my friends and I had. I always bought the lie that new, better cars were coming along. I haven’t found that to be true.
 
A56 said:
As stated above E55 denoted the 340 cu. in. motor. Had nothing to do with horsepower. Even the AAR and T/A were E55 and their hp rating was 290.
Click to expand...
OK, did not know that. Explains a lot.
 
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