79 300 susp onto 74 Roadrunner?

1975 - 1979 Mopars

  1. guitarguy

    guitarguy Well-Known Member

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    Hi, hate to double post but it was suggested I post this here.

    Have a 79 300 I love to drive and a 74 Roadrunner project. At the risk of needing future therapy for it...

    Would the entire K frame & steering box including brakes etc., wheel to wheel, from a 79 300 (you know, the Cordoba with all the cop goodies) bolt right in to a 74 Roadrunner? What about other stuff - 9 1/4rearend & springs?

    The 79 is a driver; the 74 (was 318, 8 1/4)has been sitting for decades, missing front brakes, no drivetrain. Just curious about the 79-74 interchange before I consider it.

    I know the Bs changed a lot in 73; anything chassis-wise between 74 and 79 I should know? Thanks! ~Scott in TX
     
  2. cudazappa

    cudazappa Active Member

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    In the front end, the only difference is the disc brake setup (the 79 300 got the 11.75" rotors, and slider calipers). All this means is that order for a 79 300 at the parts houses for replacement parts.

    In the rear end, there were more changes, but it mainly deals with the sway bar setup and the iso-clamp arrangement. 79 has the bar under the axle, and the iso-clamp is "upside down" and uses different shocks than the 74.

    but as a whole assembly, yes, you can swap the k-frame and rear end from one to the other.
     
  3. 1toolguy

    1toolguy Well-Known Member

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    There is one other diference in the front end: The torsion bars were lengthened in 75 and are ony interchangable with other 75-79 b-bodies. The good news is that there are reproduction and peferormace t-bars for the 74 and earlier cars.
     
  4. cudazappa

    cudazappa Active Member

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    That's wrong. Changeover year is 73 to the longer torsion bars. And yes, performance bars are available for the 73-79 B-body as well. Most notably from firm feel http://www.firmfeel.com/torsionb_b3.htm
     
  5. 1toolguy

    1toolguy Well-Known Member

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    Thanks for the update, I was told the 75 was the change changeover year.
     
  6. 76 Doba

    76 Doba Well-Known Member

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    Save the 300, I'd consider trading two 76s(one is a driver) for it.
     
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