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Just looked at the 2020 spec sheets posted recently on the forum, can't help but notice the differences between the hp & torq./rpm between the manual vs automatic spec. I knew my old '13 R/T had a different motor spec than the auto cars, the 2020 spec I just read reads much the same as my '13's.
2020 automatic makes 372 hp @ 5,200 rpm & 400 lb-ft @ 4,400 rpm 2020 manual 375 hp @ 5,150 rpm & 410 lb-ft at 4,300 rpm.
The auto cars can also run on 87 octane whereas the manual cars require 91.
I'm more surprised that the slightly higher output comes with slightly lower rpm and just to add to the mystery further, my 2015 SRT392 manual has the same motor spec as the automatic car???
Sorry if this has already been addressed, but do the R/T differences come from mechanical changes or just the tune,
 

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The spark and fueling between the auto and manual are different. I will see if I can find the post where I showed the differences in spark and fueling. Also, autos can run a lower octane 89 whereas manuals have a minimum requirement of 91. I have run 87 when my M6 RT was stock and the engine was playing...Knock...Knock....Knocking on Heaven Door.

BTW if you ever look at the VE tables on the autos they are bumpy as hell compared to the manuals...it's a good thing the PCM does not run off them directly...yuck!
 

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2013
A5 . . . 2.25" exhaust
M6 . . . 2.50" exhaust

And I bet they just kept the same rating to save $$.


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2013
A5 . . . 2.25" exhaust
M6 . . . 2.50" exhaust

And I bet they just kept the same rating to save $$.


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I thought after 2017 all 5.7s have 2.75"? Honestly the tunes are different. From what I remember the manuals ran a touch more spark. BTW the tune that comes with crate engines is identical to the manual...probably because the crate motors are not MDS.
 

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Yes true on the exhaust but apparently it costs a lot of money to certify and rate these engines. I'm sure the M6 tune is slightly different but not much but 3 hp between it and the exhaust should be easy. The 5.7L in the 300 is rated at 363 hp but I bet it makes more than that now. Just not worth their trouble to change it I guess.



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I remember seeing an updated 5.7 crate motor dyno chart somewhere (like shown below) which I always took as "ideal". The chart below is close to what my 2013 JGC 5.7 is rated at. Now I want to compare my JGC stock tune to a stock auto challenger tune.
 

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I thought after 2017 all 5.7s have 2.75"? Honestly the tunes are different. From what I remember the manuals ran a touch more spark. BTW the tune that comes with crate engines is identical to the manual...probably because the crate motors are not MDS.
and the crate motor is rated @ 383 hp / 417 fpt
Something's not advertised correctly :unsure:

345 CRATE HEMI® ENGINE Now you can own the same legendary 5.7L HEMI® Engine found in the 2015 and newer Dodge Challenger. With 383 hp and 417 lb.-ft. of torque, this complete engine assembly includes a water pump, flywheel and clutch, front sump oil pan, intake manifold with throttle body, fuel injectors and coil packs. Features: • 345 cu. in. • 99.5mm Bore • 90.9mm Stroke • Cast Iron Block (P/N 53021214DR) with 4-Bolt Powder Metal Caps • Nodular Iron Crank Material • Powdered Metal Connecting Rods • Nodular Iron Camshaft • Aluminum, Hemispherical Chamber Cylinder Heads • 52.1mm Intake Valve Size • 39.4mm Exhaust Valve Size • 10.5:1 Compression Ratio • 5,600 Peak RPM 5.7L HEMI® Engine P/N 1 68303088AA
 

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Less drivetrain hp lost through a manual transmission too....
 

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and the crate motor is rated @ 383 hp / 417 fpt
Something's not advertised correctly :unsure:

345 CRATE HEMI® ENGINE Now you can own the same legendary 5.7L HEMI® Engine found in the 2015 and newer Dodge Challenger. With 383 hp and 417 lb.-ft. of torque, this complete engine assembly includes a water pump, flywheel and clutch, front sump oil pan, intake manifold with throttle body, fuel injectors and coil packs. Features: • 345 cu. in. • 99.5mm Bore • 90.9mm Stroke • Cast Iron Block (P/N 53021214DR) with 4-Bolt Powder Metal Caps • Nodular Iron Crank Material • Powdered Metal Connecting Rods • Nodular Iron Camshaft • Aluminum, Hemispherical Chamber Cylinder Heads • 52.1mm Intake Valve Size • 39.4mm Exhaust Valve Size • 10.5:1 Compression Ratio • 5,600 Peak RPM 5.7L HEMI® Engine P/N 1 68303088AA
That is the description I remember but there was also an actual dyno chart included.
 

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Here are some tune comparisons between a 2015 Auto and Manual. Not really trying to show the manual makes more power but there are differences.

This VE table comparison, note that auto is pretty rough. Apparently both tables are way off and the engine would run like crap if you turned off the Neural Network (i.e. PCM runs off tables rather than algorithms). Fortunately these tables are essentially ignored by the PCM.
978108


Here is a comparison of the WOT spark table. In general the manual runs more spark. As a side note, both have identical knock sensor settings. Usually being able to run more spark advance equates to more power.
978109


Here is a comparison of the WOT power enrichment. Manual runs a little more fuel in some RPM bands but also runs a little less in others. Really difficult to conclude anything here but again, just showing differences.
978110
 

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Manual camshaft is slightly different because it does not use MDS and also has slightly higher compression as well.
 

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Just looked at the 2020 spec sheets posted recently on the forum, can't help but notice the differences between the hp & torq./rpm between the manual vs automatic spec. I knew my old '13 R/T had a different motor spec than the auto cars, the 2020 spec I just read reads much the same as my '13's.
2020 automatic makes 372 hp @ 5,200 rpm & 400 lb-ft @ 4,400 rpm 2020 manual 375 hp @ 5,150 rpm & 410 lb-ft at 4,300 rpm.
The auto cars can also run on 87 octane whereas the manual cars require 91.
I'm more surprised that the slightly higher output comes with slightly lower rpm and just to add to the mystery further, my 2015 SRT392 manual has the same motor spec as the automatic car???
Sorry if this has already been addressed, but do the R/T differences come from mechanical changes or just the tune,
its the tuning and cam profiles [non-MDS] and the exhaust system. there's torque management for any ATX to save the bearings and clutches that aren't necessary for MTX

also A8 R/T require 89 grade
 
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Hal H
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