How much H.P. can the 8.2 Handle ?????

Discussion in 'Got gears?' started by ToddsGS, Jan 18, 2021.

  1. ToddsGS

    ToddsGS Founders Club Member

    I'm looking to put the Factory 8.2 - 10 Bolt back into my "stock appearing Stage 1 but concerned as to how much H.P. & Torque these rears can handle. . . .

    My combination will be right around 500 HP - 550 TQ

    I plan to upgrade the Axles and Yoke.

    Anyone running an 8.2 with 500 + HP ???

    Anyone wreck an 8.2 and what was the issue ? (What should I address) ?

    I have an Auburn Posi Unit with Fabcraft Gears.

    Any comments on this are welcome!

  2. Mark Demko

    Mark Demko Well-Known Member

    Its not so much horsepower as it is torque and traction.
    With street tires and just spinning theres not much load.
    With traction and a ton of torque the load is large.
    With traction, torque, and weight, the load is HUGE, (think Kenworth, Peterbilt, Freightliner, etc.) OTR trucks have humongous rears, not big hp considering their torque at like 100 rpm:D They have traction, boatloads of torque, and TONS of weight to get rolling.
    This really didnt answer your question, so it depends:cool:
    I think for regular driving and a few passes at the track, you'll be ok.
  3. Golden Oldie 65

    Golden Oldie 65 Well-Known Member

    You can break anything if you try hard enough but a couple examples that I personally know of both involve `69 GTOs. One has a 461 stroker that produced 586hp and 590lb.ft. of torque at the flywheel and he is still running the original 8.2" 3.55 posi and Muncie M20. No track time, just street driving but he's not careful with the car by any stretch of the imagination. The second example involves a RAIV, automatic and the original 8.2 with a 4.33 gear. He has run a best of 12.17@112mph on slicks, no rearend issues so far.
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  4. TheEternalDance

    TheEternalDance Well-Known Member

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  5. monzaz

    monzaz Jim

    FActory installed ...they obviously thought it was enough. :) so for the street you are fine....AS LONG as you install the gears and posi in correct... lol.
    Even track as long as you are reasonable not expecting to run 10.90 it will hold.
    Stick cars will torture the drive line components more especially if you the driver are rough on launches.
    Automatic everything will have a slight more cushion on launches.

    JD Race
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  6. Brett Slater

    Brett Slater Super Moderator Staff Member

    Isn't that the best part of a stick car? :D:D
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  7. Guy Parquette

    Guy Parquette Platinum Level Contributor

    Pop Kennedy Stripped part of the gears off the ring gear and chipped some of the gears from the pinnon on the original 8.2 dif. The rest of it looks fine. (have the complete original rear)

    Remeber also the #4085 GSX Stg2 car, Dave B. and Doug J. changed out the broken 8.2 rear in the staging lanes. I think, before the run against the GTO ram air4.
    Last edited: Jan 19, 2021
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  8. Bigpig455

    Bigpig455 Fastest of the slow....

    I saw a 13 second 4 spd Tempest 400 snap the case in half at the 2017 PSMCDR, I mean it wrecked EVERYTHING! and I believe that was a nodular iron case too. But other than that, in the stock tire world these seem to hold up as well as anything else. I've seen 12 bolts and Ford 9's fail too. I like an 8.5 better, but Idont have any specific issue with an 8.2
  9. ToddsGS

    ToddsGS Founders Club Member

    Good input guys. Thanks

    My car has already went into the 11's and a new motor and Full Frame off is currently in the works.

    I expect to be in the low 11's with the new combination but HP will be 500 Max so I'm not setting the world on fire with HP.
    The car is set up really good and will be even better after the restoration and new Motor.

    I don't think 500 HP is to much for the Auburn Pro Posi Unit that's in it and I'll be purchasing some new axles soon.

    The car had a 12 bolt in it but I'm on a 30 year mission to prove how fast these cars are without any visible aftermarket parts so putting the 10 Bolt in is part of that plan.
    I just don't want to explode it on the launch . . . . especially after a fresh frame off!

    Still not sure what to do. I really think it's "Boarder Line". I just know the 12 Bolt doesn't belong there. :)
    I've tried real hard to utilize the factory parts with this build.
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