Engine RPM at Highway speeds?

Discussion in 'General Discussion' started by Tincup, Dec 18, 2018.

Car Parts
  1. Tincup

    Tincup Full Access Member

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    This question is for the automatic guy's. What engine RPM are you running at 70mph? assuming stock 4:56 gears and 305/40/22 tires. Thanks...
     
  2. rottenronnie

    rottenronnie Well-Known Member Supporting Member

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    2150 (O/D, converter locked)

    In other words, as slow as it's going to turn at 70 mph.
     
    Last edited: Dec 18, 2018
  3. shorty

    shorty Full Access Member

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    I'l have to slow down to 70 and look. :burnout:
     
  4. trussman

    trussman Active Member

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    I know you got an answer already Tincup but is a 6-speed swap out of the realm of possibilities? Lower RPM and turns the QC into much more of a beast ;)
     
  5. Tincup

    Tincup Full Access Member

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    Thanks everyone, That's perfect, I was hoping to be around 2100rpm, all the online calculators say it should be around 2400rpm. I was considering changing to 4:10's.
     
  6. shorty

    shorty Full Access Member

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    2100 from my QC yesterday
     
  7. trussman

    trussman Active Member

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    Personally I would only do that if you had some good power adders. Otherwise you'll increase the heavy pig feel :(
     
  8. rottenronnie

    rottenronnie Well-Known Member Supporting Member

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    If you want to greatly reduce that heavy pig feel, buy a good converter it makes a world of difference for general driving around.

    2150 (or so) isn't a lot of rpm for a performance-style camshaft so if you have one and are considering slowing your engine down, throttle response and gas mileage can take a hit.

    It depends on how big a cam and how much you want to slow it down and/or if you care about that stuff.

    Cheers and Merry Christmas (or whatever you prefer for holiday greetings) :)
     
    Last edited: Dec 20, 2018
  9. Tincup

    Tincup Full Access Member

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    Here is a pic of my truck, should weigh in just over 4000lbs, so It shouldn't feel like a heavy pig.

    131small.jpg
     
  10. Slitherbeast

    Slitherbeast Well-Known Member Supporting Member

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    It will be lighter than the stock trucks....
     
  11. trussman

    trussman Active Member

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    HAHA I totally forgot.