HP Exhaust Manifold Conundrum, 2.25 vs 2.5 inch

Mopar Exhaust Systems

  1. Camshaft

    Camshaft Member

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    IMG_4078[1].JPG Gentlemen: Hauled out some HP exhaust manifolds that have been sitting on a shelf for a few years, (17 to be exact). Went through the casting numbers on them. I have one manifold which is 2843247, (numbers are a little blurry), which shows as LP with a 2.25 Inch exhaust, but just measured it and it is 2.5 inches, which is the same as the other side 2808900 which is 2.5 inch as well. Not sure what to think of this other than they will do the job on a 440, which is where they came from (67 New Yorker parts car). Any thoughts here?

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  2. FURYGT

    FURYGT Senior Member

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    They both appear to be '67 - '69 C Body HP manifolds and should work just fine with a 440. The right side manifold was used for several more years and was also used on B Body MOPARS for several years. It would help to know what car you would be putting these in.
     
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  3. Camshaft

    Camshaft Member

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  4. Camshaft

    Camshaft Member

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    67 300 Ragtop. I have the originals for my convertible, 440 TNT. I took the originals to have them powder coated about 20 years ago and got them back in quite a bright silver instead of the gun metal grey I requested. These ones are nice, so if I don't like the silver ones once mocked up on the engine, I can use these instead. My confusion was over the casting numbers, as the 2843247 part number comes up as a LP Manifold with 2.25 inch exhaust? This is certainly a 2.5 inch HP piece. CG
     
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  5. oldkimmer

    oldkimmer Member

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    I just checked my book also. Says 440 C body low performance. Could be a misprint. Kim