Swapping My 250 To A 289?

Discussion in '1965 - 1973 Classic Mustangs -General/Talk-' started by Cbaker54, Dec 11, 2013.


  1. Cbaker54

    Cbaker54 New Member

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    I have a 1969 coupe and I'm planning to swap my 250 straight six with a 289 hipo soon, I'm having a hard time on trying to figure out what I'll have to replace in my car for it to work so if you have any information that can help that would be great thanks.
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  2. rbohm

    rbohm Founding Member

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    not much really. the 250 uses the same bell housing bolt pattern as the 289, so the V8 will bolt up to the transmission, and the rear end should be an 8" already, so no changes there. the transmission is already strong enough for the V8 so again no changes there. the front suspension is the same, including the spindles, though the springs may need to be upgraded to a stiffer set, i recommend the GT springs front and rear.

    things that will need to be changed are;

    the chassis mounts that the engine mounts bolt to
    the radiator outlets depending on what water pump you use
    and all the usual bits and pieces like wiring, linkage, fuel lines etc.
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  3. horse sence

    horse sence Please don't call me Mom SN Certified Technician

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    make sure you by the 67 -70 frame brackets motor mounts .65-66 are different and the motor will not set on them correctly.
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  4. rbohm

    rbohm Founding Member

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    good point HS
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  5. Cbaker54

    Cbaker54 New Member

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    Thanks for the information, I guess it's not a normal thing to go from a 250 to a 289. I've been searching on what the differences are but everything was about converting to a 351.
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  6. horse sence

    horse sence Please don't call me Mom SN Certified Technician

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    289,302 and 351 are basically the same in the motor mounts .the 351 is taller and wider
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  7. rbohm

    rbohm Founding Member

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    actually swapping a six, any six, for a V8 tends to be the norm for most people. keeping the six and building it is being different. and the 250 can make for a really nice healthy street motor given a chance. let me know if you want ideas on building the six instead.
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