Gear Ratio

Discussion in 'Drivetrain' started by RyanCess, Jan 1, 2016.

  1. RyanCess

    RyanCess Member

    Messages:
    132
    Likes Received:
    0
    Joined:
    Nov 4, 2015
    What would be the best gear ratio to get for my 3.8L V8 if I were to get racing gears for my car?
     
  2. 96blak54

    96blak54 Legend

    Messages:
    7,485
    Likes Received:
    804
    Joined:
    Feb 21, 2011
    Location:
    Ky
    I may be wrong and others will chime in, but im thinking the v6 cars came with 7.5" rearend ring gears and the v8 cars came 8.8". Im not sure where v6 parts could be purchased. Do you know what the rear ratio is in the car now? Ford mounted a tag to one of the rear diff cover bolts with numbers stamped on it. Get under the car and check it out. Report back.
     
  3. the5.ohh

    the5.ohh Legend

    Messages:
    9,555
    Likes Received:
    108
    Joined:
    Oct 15, 2012
    Location:
    Shaolin, NY
    If it's an automatic go 4.10 Gears, if it's a stick shift go 3.73 Gears. Only buy Ford Racing! Best gears to get.
     
  4. Orange 94

    Orange 94 Moderator Staff SN95 Supporter

    Messages:
    10,855
    Likes Received:
    387
    Joined:
    Oct 21, 2012
    Location:
    Alberta Canada
    7.5 with 273s. You can purchase gears at most places like American muscle.

    Switch to 373s. Look into limited slip as well.

    Ideally you would source a 8.8, rebuild it and swap it in.
     
  5. RichV

    RichV Well-Known Member

    Messages:
    4,227
    Likes Received:
    247
    Joined:
    May 6, 2012
    Location:
    CO
    3:73 gets my vote too. You can get a limited slip 7.5, they're out there as well.

    CL usually has 8.8 rears, some already have the gears in them ready to go. You can get a Fox 8.8 and swap in your brakes and axles too.
     
  6. RyanCess

    RyanCess Member

    Messages:
    132
    Likes Received:
    0
    Joined:
    Nov 4, 2015
    And what exactly do the gears do? I read that it changes the powerband of the rpm's. Is that's right? I'm a noob :/
     
  7. RyanCess

    RyanCess Member

    Messages:
    132
    Likes Received:
    0
    Joined:
    Nov 4, 2015
    And what's the difference between the 373's and the 410's?
     
  8. RyanCess

    RyanCess Member

    Messages:
    132
    Likes Received:
    0
    Joined:
    Nov 4, 2015
    What else do i need besides the ring and pinion gear? I'd most likely have a shop install them.
     
  9. 96blak54

    96blak54 Legend

    Messages:
    7,485
    Likes Received:
    804
    Joined:
    Feb 21, 2011
    Location:
    Ky
    The 7.5 gear set can be swapped in with no other components. The shop should be competent enough to use the exsisting bearings assuming the rear has no proplems now.

    Buy FordRacing proper rearend gear set of your choice size and take to a shop. Roughly $200labor

    If the rear gear in your car now is a 2.73, switching to a lower ration (although numerical higher) 3.73 or 4.10 will multiple the torque out put at the rear wheels. Or you could look at it like this....your 1st gear now can top 50mph at redline. Swap in the 4.10 and it will be 25mph. The same applies to the other gearing speeds. The car will feel quicker off the line and the engine load will be less
     
  10. RyanCess

    RyanCess Member

    Messages:
    132
    Likes Received:
    0
    Joined:
    Nov 4, 2015
    would they need any other components to do the 3.73? That's what I plan on getting.
     
  11. g36 monkey

    g36 monkey Moderator Staff SN95 Supporter

    Messages:
    14,057
    Likes Received:
    539
    Joined:
    Nov 15, 2008
    Location:
    Orlando, Fl
    Alright, I would personally try to find a good shop by you. A lot of places around here, would not install gears unless we bought from them. They also would not install any gears that were not Ford racing.

    As mentioned, ideally you would find an 8.8 rear end and get that rebuilt with new gears, then just install it. I wish I had done this.

    However, you basically just need to order an install kit. Some shops don't have the 7.5 stuff sitting around, but every shop should have 8.8 stuff.
     
  12. RyanCess

    RyanCess Member

    Messages:
    132
    Likes Received:
    0
    Joined:
    Nov 4, 2015
    And the 7.5 rear end is what I have?
     
  13. Orange 94

    Orange 94 Moderator Staff SN95 Supporter

    Messages:
    10,855
    Likes Received:
    387
    Joined:
    Oct 21, 2012
    Location:
    Alberta Canada
    Yes
     
  14. RyanCess

    RyanCess Member

    Messages:
    132
    Likes Received:
    0
    Joined:
    Nov 4, 2015
    And the 3.73 gears can fit in the 7.5? I think I'm getting it now. I just have to ask the shop if the have the right equipment for my rear end?
     
  15. Orange 94

    Orange 94 Moderator Staff SN95 Supporter

    Messages:
    10,855
    Likes Received:
    387
    Joined:
    Oct 21, 2012
    Location:
    Alberta Canada
    373 gears made for the 7.5 will install in the 7.5
     
  16. g36 monkey

    g36 monkey Moderator Staff SN95 Supporter

    Messages:
    14,057
    Likes Received:
    539
    Joined:
    Nov 15, 2008
    Location:
    Orlando, Fl
    Bingo, the GT cars came with an 8.8, the V6 a 7.5 without a limited slip, so we have the curse of the "one wheel peel"
     
  17. RichV

    RichV Well-Known Member

    Messages:
    4,227
    Likes Received:
    247
    Joined:
    May 6, 2012
    Location:
    CO
    Going from 2:73 to 3:73 is similar to riding a Mountain bike. When it's hard to peddle, you downshift by moving the rear gear to a larger sprocket. It's easier to peddle, so in the car the motor will be able to rev up faster.
     
  18. RyanCess

    RyanCess Member

    Messages:
    132
    Likes Received:
    0
    Joined:
    Nov 4, 2015
    So by doing his my car will be torquier? And what is one wheel peel? Lol
     
  19. wmfateam

    wmfateam Active Member

    Messages:
    725
    Likes Received:
    3
    Joined:
    Aug 23, 2013
    Location:
    Gilbert, AZ
    It will feel torquier. No actual power is gained. Jump on a mountain bike and do the experiment mentioned earlier. The one wheel peel is, for example, you are at a stop light, you rev up and drop the clutch. Because it is an open differential, all of the power will go to one wheel and spin while the other tire will just move like a front tire. You can Google how a limited slip works.

    Sent from my XT1254 using Tapatalk
     
  20. g36 monkey

    g36 monkey Moderator Staff SN95 Supporter

    Messages:
    14,057
    Likes Received:
    539
    Joined:
    Nov 15, 2008
    Location:
    Orlando, Fl
    A limited slip differential is way better for handling and taking off. The one wheel makes for a lot less traction. If you get gears for the 7.5 I would get a limited slip differential put in place. I believe some rangers came with them.