250 and 300 i6 engines HELP

Discussion in 'Technical' started by 75comet, May 29, 2007.

  1. 75comet

    75comet Member

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    Ok, i have a 75 comet, the engine locked up in, stock was the 250, but my uncle gave me a 300 that is fuel injected. Problem is, what all needs done to put the carb on it? he told me just to swap intakes? but i think it needs the whole head swapped, and sitll not sure about fuel pump, and the electronics on the distrubitor


    any help?
     
  2. badmav70

    badmav70 Member

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    intakes dont swap on the 250... there are places you can get adapter plates to put on differnt carbs though... fordsixparts.com is one of them... bewere though you may end up with hood clearence problems.... thats a day killer there when a wingnut goes through your hood:slap:
     
  3. 75comet

    75comet Member

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    thats what i was noticing that the intakes dont wap, thats why i suggested heads? but can you even swap out heads?
     
  4. badmav70

    badmav70 Member

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    missing my 71 maverick i6 3 on the tree :(
    i do beleave the head is longer on the 300.. but im no expert... you like your six you should check with the guys at fordsix.com fourm... very cool info there. and there is a mav/comet section(y)
     
  5. RabidCustoms

    RabidCustoms sic minds demand sic toys

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    the 250 and 300 are different series engines. they wont interchange heads. and the 300 would require a fair amount of work to make it fit. the head and intake is integral on the 250, the intake on the 300 is removable.if you were to try and swap these two engines, you would need a hi-pressure fuel pump,or switch to a carb,sort out the electrical differences,fabricate motor mounts as it wont just bolt in the same as the 250, have exhaust made, ect.

    not saying it hasnt been done, or cant be done,...but it does require a fair amount of work.

    I would suggest, you would be better off finding another 250, rebuilding yours or swapping to a 302.

    if you have the time, money, and skills then you "could" go with the 300.

    good luck on it.
     
  6. 75comet

    75comet Member

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    go figure, i knew i shouldnt have listened to my uncle lol... i am not a ford man to tell the truth... was going to redo this car with my girlfriend so she can drive it

    I do have the skill and time, but we were not looking to spend the money, so maybe she will end up wiht a 302 in it as i already have the mount for that
     
  7. newtoford

    newtoford Member

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    the biggest issue with going to a 240 or 300 block is that they are longer and the radiator will have to be moved up. the motor mounts will have to be custom made as well. the only reason to go with one would be the coolness factor, if you want power go 8. to my knowlege nothing is interchangable between the small sixes found in mavericks 144-170-200-250 and the big block sixes found in trucks and vans 240-300.

    there is an aftermarket if you wanted to do i performance 6 build.
     
  8. 75comet

    75comet Member

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    just want to get the car running... i might try to rebuild the old engine as it only has 50k original miles, but was stolen and hotrodded and we bought it, drove ti a bit, then it locked up.. yes it had oil and everything
     
  9. Slantsickness

    Slantsickness Member

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    Probably a spun bearing. Overreving the engine can weaken the bearing shells.
     
  10. PaulS

    PaulS Member extrordiare

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    Why not just put a short block 250 and swap over your head and tin?
    It has to be faster and cheaper than installing a 302.
     
  11. Bluegrass

    Bluegrass Jr. mbr. not really,

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    This car was originally built in Easton, Pa. 1972.
    One of the original builder/owners now lives in Ct. and last worked for restoration Mustang shop.
    Car has passed thru several owners and was last known to be a mid 11 sec. quarter miler.
    The motor shown is a 300 cu/in based truck motor of unknown modifications internally
    The carbs are Webers, with magneto ignition shown..
    Photo was taken at Englishtown drag strip on a Ford weekend show some years ago.
     

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