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Fate of the Hemi 5.7?

Discussion in 'Mopar / FCA News' started by andronikus, Feb 27, 2016.

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  1. grungerockjeeper

    grungerockjeeper Well-Known Member

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    So how would this low sulfur fuel affect older engines? Is it going to be a scenario like when unleaded became the norm and you either ran lead additive or had to rework the valve seats to cope?
     
  2. grungerockjeeper

    grungerockjeeper Well-Known Member

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    Some guy on youtube has a setup like that on a /6. Its pretty sick!
     
  3. grungerockjeeper

    grungerockjeeper Well-Known Member

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    Id define 'safety' a bit differently then. One such delay occurred right as I came out of the 26 West tunnel out of Portland. My truck caught up to my lead foot right as I exited the tunnel (back onto wet pavement) and I found myself sideways! Luckily no one was on my right quarter...
     
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  4. Mike V.

    Mike V. Mopar-nac The Moderator

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    The formulation is different and it is called "low sulfur" because it has a lower content of sulfur in it. Sulfur is not a catalytic convertir destroyer like lead was/is (since you mentioned the unleaded fuel change over) but it is an inhibitor which strongly competes with the other exhaust pollutants on the catalyst surface. When combustion occurs, fuel sulfur is oxidized mostly sulfur dioxide (SO2) and a small amount of sulfur trioxide (SO3). SO2 and SO3 are known to inhibit the function of the catalytic convertor.

    The affects of sulfur vary based on gasoline sulfur level, the catalyst formulation, catalytic function, combustion products from various air/fuel mixtures, and exhaust temperature range.

    As for carbon build up, low sulfur fuels have been shown to have lower particulate matter content emissions upon combustion, which will help with DI engines and the occurrence of build up.

    No, it won't affect valve seats but may require some changes in carburetor tuning on older vehicles because of changes in air/fuel mixture and combustion temperatures when burning low sulfur gasoline.

    Mike
     
    #84 Mike V., Mar 3, 2016
    Last edited: Mar 3, 2016
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  5. redhed

    Level III Supporter

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    so what it boils down to is that while catch cans are nice...and "cleaner" burning gas is nice...they aren't the complete answer to eliminate carbon buildup on the intake valves. :cool:
     
  6. Mike V.

    Mike V. Mopar-nac The Moderator

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    If that's the conclusion you want to make... However, that's not what I said. ;)

    Mike
     
    #86 Mike V., Mar 3, 2016
    Last edited: Mar 3, 2016
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  7. ptschett

    ptschett Well-Known Member

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    Depends on the definition of "drone". I had a 2010 5.7/6-speed manual for about 4.5 years which I traded for a 2015 5.7/8-speed automatic about a year ago. While I think the steady-state or gentle-acceleration sound of the engine in 4-cylinder MDS mode (after all that experience with the non-MDS manual setup) can be a little weird, I wouldn't call it objectionable at all.
     
  8. Max Wedge

    Max Wedge Well-Known Member

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    That would be my guess in this situation perhaps one of the other guys here could give you some better more detailed answer.
     
  9. Doug D

    Doug D Virginia Gentleman

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    Never really noticed any sort of MDS drone with my '06 1500, but then mine did not have dual exhaust. I think it's more noticeable if there is dual exhaust.
     
  10. MPE426HEMI

    MPE426HEMI Well-Known Member

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    Never hear any weird drone noises out of my '06, with duals when I had MDS, but then I never took my foot out of it anyways.:)
     
  11. aldo90731

    Staff Member Level III Supporter

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    The reason I ask is my 2012 300 SRT 6.4 HEMI with 5-speed droned at freeway speeds. It drove me bananas.

    My Challenger 392 with 6-speed didn't have MDS, so I didn't hear it in it.
     
  12. MPE426HEMI

    MPE426HEMI Well-Known Member

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    I have mine deactivated, but when I had it on, I never noticed any irritating drone at highway speeds. I've read somewhere that the dual exhaust was set up in such as way as to combat this. Changing over to an aftermarket exhaust however, may produce it.
     
  13. Dave Z

    Dave Z It's me, Dave
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    And for those who don't remember what it's like to have older cars... we have to tune the carburetor on a regular basis anyway...so it shouldn't really matter. Aside from refiners' conversion costs, this is really a no-lose change.
     
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  14. GasAxe

    GasAxe Well-Known Member

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    @ MRGTX
    What happens when your aluminum block becomes heavier than an iron block because of durability issues? There are very good reasons for keeping "old" technology in service and aluminum does not always equal lighter.;)
     
    #94 GasAxe, Mar 4, 2016
    Last edited: Mar 4, 2016
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  15. valiant67

    valiant67 ...

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    Carburetor tuning , points and plugs were all about once a year issues.
     
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  16. Mike V.

    Mike V. Mopar-nac The Moderator

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    The ethanol mixed in the fuel causes more issues with older cars than the reduction of sulfur content in new formulations will.

    Mike
     
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  17. Dave Z

    Dave Z It's me, Dave
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    I did the carb tuning twice a year but my car had over a hundred thousand miles (pick one, any car.) Yes, the ethanol is a bigger issue ... though it's not the end of the world, either. Unfortunately it seems unlikely a better solution will be found since ethanol is so big in the primary states...
     
  18. Mike V.

    Mike V. Mopar-nac The Moderator

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    Careful, let's not get political :)

    But yes I agree, it's here to stay, in all its gummy nasty glory.

    Mike
     
  19. Dave Z

    Dave Z It's me, Dave
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    Sorry. You are right of course. May I just say I think it's a non-party-related issue? If you represent corn farmers, you want to see a higher price for corn. It is rather far from the fate of the Hemi, though, and we should return to that.
     
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  20. TheMan

    TheMan What color are the clouds in your world?
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    Eifh fje 11.r fo 1 zc of '5my s8 ... I do notworrry about [email protected]
     
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