Rear Gear Ratios V8 vs. 6

Discussion in 'Technical' started by Drew Hierwarter, Jun 13, 2015.

  1. Drew Hierwarter

    Drew Hierwarter Member

    Joined:
    Sep 2, 2014
    Messages:
    135
    Likes Received:
    50
    Trophy Points:
    61
    Location:
    Kingsport, TN
    Vehicle:
    1976 Comet
    I read in an earlier thread that there were only two rear gear ratios in 71-77 Comets; 2.79 and 3.00.

    Was one for V8's and the other for 6 cylinder cars? If so, which was which?

    If not then what?
     
  2. Krazy Comet

    Krazy Comet Tom

    Joined:
    Sep 13, 2012
    Messages:
    7,561
    Likes Received:
    2,319
    Trophy Points:
    531
    Garage:
    1
    Location:
    Chesapeake VA
    Vehicle:
    1972 Comet GT clone 306 . 1969 Fairlane Cobra 428CJ 1988 T-Bird awaiting 331 ..
    My '72 v8 has 3.00 the '71 200 6cyl 2.79...
     
  3. Craig Selvey

    Craig Selvey Indiana State Rep - MCCI

    Joined:
    Mar 9, 2002
    Messages:
    18,218
    Likes Received:
    1,308
    Trophy Points:
    878
    Location:
    Albany, Indiana
    Vehicle:
    1972 Maverick Grabber - Color: Orange Also, 1976 Ford Maverick 4-door, 1977 Mercury Comet 2-door.
    It was strictly an option. All the factory AC cars got 3.00 gears.
     
  4. Acornridgeman

    Acornridgeman MCCI Wisconsin State Rep Moderator Supporting Member

    Joined:
    Apr 30, 2004
    Messages:
    6,493
    Likes Received:
    937
    Trophy Points:
    426
    Location:
    Wisconsin
    Vehicle:
    70 Maverick Grabber, 72 Maverick Grabber Restomod
    It seems too the 3 speed cars had the 3.00 while automatics had the 2.79
     
  5. Drew Hierwarter

    Drew Hierwarter Member

    Joined:
    Sep 2, 2014
    Messages:
    135
    Likes Received:
    50
    Trophy Points:
    61
    Location:
    Kingsport, TN
    Vehicle:
    1976 Comet
    So my '76 Comet has an automatic but was originally equipped with A/C, sooooo . . . should it have 3.00?

    The reason I'm asking is that I need another third member and I may be able to get one from a '74 V8 car I was just wondering if that car and mine would have the same ratio.
     
  6. Craig Selvey

    Craig Selvey Indiana State Rep - MCCI

    Joined:
    Mar 9, 2002
    Messages:
    18,218
    Likes Received:
    1,308
    Trophy Points:
    878
    Location:
    Albany, Indiana
    Vehicle:
    1972 Maverick Grabber - Color: Orange Also, 1976 Ford Maverick 4-door, 1977 Mercury Comet 2-door.
    Maybe. Heck....they are so close....I don't think you could tell the difference.
     
    Ronald Hopkins likes this.
  7. Krazy Comet

    Krazy Comet Tom

    Joined:
    Sep 13, 2012
    Messages:
    7,561
    Likes Received:
    2,319
    Trophy Points:
    531
    Garage:
    1
    Location:
    Chesapeake VA
    Vehicle:
    1972 Comet GT clone 306 . 1969 Fairlane Cobra 428CJ 1988 T-Bird awaiting 331 ..
    This is probably true but a friend claimed a swap from a 2:80 to 3:00 made his son's '65 Mustang feel like a different car... I'm thinking it was more the Equa-Lock in the 3.00(nice to have some resemblance of traction), has close ratio four speed with 2.32 1st gear,
     
  8. rthomas771

    rthomas771 Member

    Joined:
    Jan 22, 2008
    Messages:
    8,010
    Likes Received:
    913
    Trophy Points:
    498
    Garage:
    1
    Location:
    GA
    Vehicle:
    '74 Maverick 250 5-Speed.'60 Falcon V8. '63.5 Falcon HT
    I notice a bit of difference between the 2.79 and 3.00. Not only picking up another mpg or two...the 3.00 keeps the engine from laboring as much at lower rpm. This was with a C4 transmission.
     
  9. Drew Hierwarter

    Drew Hierwarter Member

    Joined:
    Sep 2, 2014
    Messages:
    135
    Likes Received:
    50
    Trophy Points:
    61
    Location:
    Kingsport, TN
    Vehicle:
    1976 Comet
    At the very least there should be a difference in the speedometer reading.
     
  10. Krazy Comet

    Krazy Comet Tom

    Joined:
    Sep 13, 2012
    Messages:
    7,561
    Likes Received:
    2,319
    Trophy Points:
    531
    Garage:
    1
    Location:
    Chesapeake VA
    Vehicle:
    1972 Comet GT clone 306 . 1969 Fairlane Cobra 428CJ 1988 T-Bird awaiting 331 ..
    Agreed, you'll probably need to add or subtract a tooth on driven gear, depending on which rear you're using...
     
  11. Drew Hierwarter

    Drew Hierwarter Member

    Joined:
    Sep 2, 2014
    Messages:
    135
    Likes Received:
    50
    Trophy Points:
    61
    Location:
    Kingsport, TN
    Vehicle:
    1976 Comet
    Or just compare it with the GPS/Speedo app on my tablet and drive by the tach. :LOL:
     
  12. Crazy Larry

    Crazy Larry Member

    Joined:
    Jul 16, 2005
    Messages:
    3,557
    Likes Received:
    603
    Trophy Points:
    287
    Location:
    Wichita, Kansas
    Vehicle:
    '73 Maverick 2-door, 302, manual trans
    My '73 came with 2.79. V-8, manual transmission, no A/C.
     
  13. mojo

    mojo "Everett"- Senior Citizen Supporting Member

    Joined:
    Jul 20, 2009
    Messages:
    5,250
    Likes Received:
    818
    Trophy Points:
    498
    Garage:
    1
    Location:
    Chicago
    Vehicle:
    73 Comet GT-302 4bl
    My 73 has 2.79, factory AC and C4. I can't say that it was/is the original gear ratio, but believe it is original. There is nothing to indicate it has ever been changed, the metal tag is still on the housing/pig.
     
  14. Acornridgeman

    Acornridgeman MCCI Wisconsin State Rep Moderator Supporting Member

    Joined:
    Apr 30, 2004
    Messages:
    6,493
    Likes Received:
    937
    Trophy Points:
    426
    Location:
    Wisconsin
    Vehicle:
    70 Maverick Grabber, 72 Maverick Grabber Restomod
    My thinking is the V8 cars received the 2.79 as they had enough power to overcome any short comings created by A/C or manual transmissions. I-6 cars with a manual or A/C had the 3.00

    Does anyone else have a factory V8 car that came with the 3.00 ?
     
  15. mercgt73

    mercgt73 Member

    Joined:
    Sep 6, 2003
    Messages:
    3,828
    Likes Received:
    352
    Trophy Points:
    223
    Location:
    Eastern Shore, Maryland
    Vehicle:
    1973 Comet GT (clone), 1974 Mustang II, 1980 Bobcat Wagon
    Yep. 1973 Comet, 302, C4, factory A/C with 3.00 gears.
    [​IMG]
     

Share This Page