8.8" vs. 9"

Discussion in 'Technical' started by Rocketlad, Mar 22, 2014.

  1. Rocketlad

    Rocketlad Garage Warrior

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    I'm looking for a different rear axle for my car. I will be pushing 700+ HP and need something that can handle it. Was just wondering what are the best cars to steal one from and should I go with an 8.8 or 9? I would like a ratio of 3.55 or a little under (3.3 something would be perfect).
    Oh and rear discs already attached is a huge plus.
     
  2. Krazy Comet

    Krazy Comet Tom

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    Stock a 9" is far stronger than a 8.8", if I were pushing a honest 700Hp the 9" with at least 31 spline axles would be my only choice...
     
  3. groberts101

    groberts101 Member

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    yep.. and the 8.8 having cheaper/better brake availability would easily be overshadowed by the 9 incher not needing c-clip eliminators either.

    Not to mention the conversion to 9" is easier and cheaper with less welding required.
     
  4. Bryant

    Bryant forgot more than learned

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    the 8.8 is close to its limits at the 700 hp level. their are other factors at play that determine if the 8.8 can live at that level, like weight, traction, transbrake use or clutch, drag racing, road racing or street car.

    at the 700hp level you want to increase the axle spline count on either diff. this makes the 8.8 very expensive at this point. the 8.8 can goto 33 or 35 splines. the 35 spline ones i feel are very weak. this is because the carrier, usually a spool at this point, has very thin journals. i have seen them brake a lot. the 8.8 also uses c clip axles that would not be legal for nhra drag racing use with the times that power should give you. this would require either c clip eliminators or 9" style housing ends. this would get rid of the advantage of using the 8.8 disk brakes.

    if you are planning on very aggressive use with that 700hp like drag racing with slicks and a trans brake you need to spend money on a proper built 9". you will want 35 spline axles with a spool or detroit locker. you will want a 3.25 carrier bearing bore 9" case, a heavy duty pinion bearing support, 1350 yoke.

    i would start with a 9". get the late model big housing ends. you can use the explorer disk brakes on that housing. they can be had for cheap out of any salvage yard.
    your going to have to buy axles anyways. look at the strange st series for good ones that are not too expensive.
    try to find a used 3.25 third member on a used racing parts site like racing junk or yellowbullet to save some money.
    if you start out with 31 spline stuff you will be spending money twice in the long run.
     
  5. Rocketlad

    Rocketlad Garage Warrior

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    Thanks for the good information:thumbs2: I hate to ask you to do my shopping for me but could you post some links and some suggestions? Also, there is a yard a few miles from me with a bunch of torinos, galaxy's, etc... Can I get what I need from one of those?
     
  6. Pony Express

    Pony Express Haul'in @**

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  7. Pony Express

    Pony Express Haul'in @**

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  8. Bryant

    Bryant forgot more than learned

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    i need more info than 700hp. what transmission? what are you using the car for?
     
  9. lm14

    lm14 Member

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  10. dan gregory

    dan gregory Member

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    Just call Currie or Strange & get a whole rear end the length you want already made & be done w/ it.
     

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