Exhaust manifold interchangeability?

Mopar Exhaust Systems

  1. Fitz73Chrgr

    Fitz73Chrgr Well-Known Member

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    Hey all,

    I've got a '69 383 HP motor in my '70 Charger. I'm working on collecting components to get a new exhaust system built, and I've hit a snag:

    I ordered TTI headpipes (part# B25EP) to bridge the gap from my exhaust manifolds to the Pypes crossmember back system I bought. When I did, they asked for my exhaust manifold casting numbers and let me know that the TTI headpipes aren't guaranteed to work, as I apparently have 1967 440 exhaust manifolds. Specifically, my driverside manifold won't work.

    SO, my question is, how different are 383 drivers side exhaust manifolds such as 2843992 or 2951865 from my 1967 manifold casting 2806974? Has anyone successfully used TTI headpipes in this situation before? If I were to assume risk and purchase these headpipes, how much modification am I looking at?

    I have 3 options right now, either buy the headpipes and make yet-unknown modifications, purchase a correct manifold (which are not cheap, and drives me to my 3rd option) going all-in right now and ordering TTI longtubes.

    Thanks in advance for the help
     
  2. Jerry Hall

    Jerry Hall Well-Known Member

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    Might be less expensive to just find a good muffler shop and let them connect everything. Just get a good picture of how you want it to look. Show it to them and let them do the rest.
     
    • Agree Agree x 4
    • PurpleBeeper

      PurpleBeeper FBBO Gold Member FBBO Gold Member

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      I agree with Jerry. I think you just need to make sure you get the right flange where it bolts up to the manifolds and let the muffler guys do the rest (they can probably get them if you let them know ahead of time)
       
    • Fitz73Chrgr

      Fitz73Chrgr Well-Known Member

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      Yeah, might do that.

      I keep looking at pictures of these manifolds, and my 2806974 sure looks very similar to 2951865. Does anyone have any insight as to whether these are close?
       
    • Jerry Hall

      Jerry Hall Well-Known Member

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      Compare the places where they bolt to the head. The 67 manifold has 3 raised bosses that take the longer mounting bolts the other manifold only needs 1 longer bolt.
       
    • Jerry Hall

      Jerry Hall Well-Known Member

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      20190718_165106.jpg
      From left to right in the picture #1 #3, & #5 take the long nuts.
       
    • Fitz73Chrgr

      Fitz73Chrgr Well-Known Member

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      I see that now, thanks Jerry. It also looks like the flange is at a different rotational angle.
       
    • Jerry Hall

      Jerry Hall Well-Known Member

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      Could be as I have never put the 2 side by side.
       
    • Fitz73Chrgr

      Fitz73Chrgr Well-Known Member

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      Thanks for the help and input, all. I've decided to go a different route. I'm picking up my new TTI longtubes next week.
       
    • Dreamcatcher

      Dreamcatcher Will fish for food

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      Interesting post I am in the same situation. Decided to put a modified 426 street wedge in my 68 charger with a 6 pack. The only HP manifolds I have are from a 73 400 Magnum engine. I thought they resembled the 68 440 HP manifolds. But are possibly different on the flange. I wanted a factory exhaust system. Absolutely hate headers so that isn't an option. Anyone know if these manifolds would be the same? I also assume the exhaust systems were different from the standard 440 and HP 440.
       
    • halojumper

      halojumper FBBO Gold Member FBBO Gold Member

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      Just my 2 cents. I called accurate exhaust, and told them I'm using 1968 HP manifolds on a 383. I have a '67 B body. I was told just use the '68 head pipes.
       
    • ynst

      ynst FBBO Gold Member FBBO Gold Member

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      Yes, flange angle is significantly different
       
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