Snap an 8"?

Discussion in 'Classic Talk' started by theautomatics, Mar 12, 2008.

  1. theautomatics New Member

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    Don't quite have the money for a 9" rear end yet. Wondering if I can stick with my ford 8" locking differential. I believe it's the original 8" that was recently converted to locking diff. Here's the specs.

    1967 mustang coupe
    3.89 (locking diff)
    359 stroker from boss block, guessing 420hp at the fly maybe 360 at the wheels?
    mickey thompson p255/50r 16 street slicks
    4 speed auto rebuilt AOD trans.

    Think the 8" rear will hold for this summer?
  2. jspagna1 New Member

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    Are you going to be Drag Racing it every weekend at the track? If not you should be alright. It helps that it's an automatic. But never say never.
  3. rbohm Founding Member

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    given your combination you should be ok for the summer, but do save for a 9" rear end.
  4. 65-347 New Member

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    Your rear will never last, you should sell it to me and buy a 9'' now. :D Just kidding. It should last as long as you don't beat it to much.
  5. blown65 Founding Member

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    You will be ok as long as you don't do hard launches at the strip or get into wheel hop on the street. My 8" blew up the first time with some pretty bad wheel hop. (many many yrs ago.)
  6. edgars23 Member

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    Do you have stock axles?
  7. Vinyl66 New Member

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    I still use the 8" with my 347 and have run in the 11's a bunch of times over the last few years on 235/60 MT drag radials. The automatic definitely helps out. Wheel hop can break anything. I use Slide-a-links to cure that problem. You can break the rear with 200 hp if you have bad wheel hop.

    I use stock 28 spline axles and a Detroit locker. I also studded the pinion support for extra insurance.
  8. theautomatics New Member

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    Yea it's the stock axles and I plan on driving it quite a bit this summer. I'm having my engine dyno'd in a few weeks and I've been told it has closer to 450 hp. My search begins now for an 8.8 or 9". Thanks.
  9. edgars23 Member

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    If you are in that HP range, I would suggest a rear end that can handle it. The stock axles may be toast if you do too many hard launches.

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