Rear end question

Discussion in 'Technical' started by klynam, Mar 22, 2012.

  1. silver70

    silver70 Eric

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    If weight is an issue, also bear in mind that a stock 9" weighs about 75 lbs. more than a stock 8".

    I wonder how much more the 8.8" weighs than the 8"? If anything. Probably nominal.
     
  2. Bryant

    Bryant forgot more than learned

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    those are lockers. there are several brands of them, the most popular and the strongest is the detroit locker. there are also lockrite, power trax no slip, and some other off shore clones of the the above.
     
  3. baddad457

    baddad457 Member

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    I'd rather the extra weight (although I dispute the 75 pound difference) and have the extra strength (not to mention resale value)
     
  4. Joe Dirt

    Joe Dirt BBF life

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    To maintain the stock width the long side (driver) has to be shortened to the same leangth as the passenger side then use a passenger axle in the driver side and move the perches

    I run a explorer 8.8 with goodies after i blew my 8" apart in a car with power i wouldnt waste my time with a 8" jmho
     
  5. klynam

    klynam Member

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    So in the final analysis it sounds like the fastest/easiest way forward is the $320 posi unit on eBay, new gears at $150, and $100-$150 shop labor. Stock axles should be good for 400-450hp, and no other changes required. Total cost: $600-650.

    Yes??? No???
     
  6. klynam

    klynam Member

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    Lug nuts are tight - checked that - but I suppose there could be something else related to the spacers causing the noise. Maybe they don't sit perfectly flat against the hub???
     
  7. klynam

    klynam Member

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    Funny thing - after I started this post I was looking around online and it's crazy how many old-school hot rodders say the Maverick rear end is the one to have since it's "already pretty narrow and holds up great to power."

    But YOUR car is another world entirely when it comes to power! :bananaman
     
  8. Bryant

    Bryant forgot more than learned

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    i would say stock axles are at there limits at around 400 hp. it really depends on 4 things. weight of the car, horse power, of the car, traction, and how the power hits the rear end. is it a trans brake automatic, or just a auto or a aggressive clutch stick shift. these are the main factors that i consider on weather or not to upgrade axles.
     
  9. klynam

    klynam Member

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    Great points and I know you're not speaking to my situation particularly, but to readers in general.

    Even though I'm just dreaming, I can't imagine having 400hp in our car. Not with our budget and other issues. If I could even get to 300hp with 3:73's and a posi someday, we'd have all the fun we wanted...
     
    Last edited: Mar 23, 2012
  10. bmcdaniel

    bmcdaniel Senile Member

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    I have a 70 Mustang 9" in mine, 2" wider on each side. My wheels are 15 x 8 w/ 6" of back space. Bought the housing, center section w/Trac Loc used from a friend for $500, new gears, rebuild kit, brakes, everything else. Grand total about $800.
     
  11. maverick1970

    maverick1970 MCG State Rep

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    The Maverick/Comet rear is in demand by the street rodders. Just think how many cars were parted just for the rearend.
     
  12. silver70

    silver70 Eric

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    You would be absolutley right to dispute it, too. I almost wrote 50-75 lb. difference. It kinda varies with internals used and casting types.

    Also, to the OP, don't go for the "Strip" gear sets that are sold, for your particular use, perhaps believing them to be stronger. The "race only" gear sets are made from a softer steel compound to take the abuse of a high-rpm transbrake beating them up constantly. This is so the teeth don't shear off under extreme loads. Guys are constantly replacing these. You want a good street/strip set. These will be a harder steel that is made to wear gradually.


    Also, x2 for the vehicle specs affecting the 8" capability. As mentioned earlier, slicks and a heavy car (like a Torino or something) will beat the hell out of an 8". With a car as light as a Maverick, on street tires, you will not be getting enough traction or applying as much force to trash the diff.

    Just as an example, if you are curious, I gutted my car of the interior, have aluminum parts on the motor that made 386 horse/372 ft-lbs torque, and ran street tires. I beat up quite a bit on that stock 8" and never had a problem. I am now in the process of changing gears/posi and did a thorough inspection of the parts, including a gear runout to test for deflection. Everything checked out great. No abnormal wear patterns, axle spline stress, or potential bearing issues.

    The 8" is stronger than most people think. Provided you're not thinking "drag car." :)


    Rebuilding the diff is not beyond a mechanically-inclined person, either. You could do it at home. With a large vise, dial indicator with magnetic base, homemade spanner wrench, and digital caliper to check shim thickness and bearing sizes. Might be able to offset the shop fees some and the tools can be used multiple times. I've done a few this way with zero issues. Just take your time.
     
  13. maverickoutlaw

    maverickoutlaw Member

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    If you are running more than 350hp you need to invest your money in a 9" or 8.8. An 8" will not hold up.
     
  14. baddad457

    baddad457 Member

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    Yea, if you're comfortable spending that much money and still have an 8 inch.:huh: Or spend an equal amount and have a 9, and have both the extra strength, plus the resale value a 9 adds to the car.
     
  15. klynam

    klynam Member

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    No I'd rather have the 9" of course - but I didn't see that happening for $650 unless I just got crazy lucky at a swap meet or something. Considering everything that has to change, it sounded to me like a 9" was going to run upwards of $900-$1000 on a good day...???
     

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