Th400 2 speed or 3 speed

Discussion in 'PSI Superchargers Tech Questions' started by Hk_radial, Sep 12, 2020.

  1. Mike Canter

    Mike Canter Top Dragster
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    Problem with a lock-up is the limited life of the differential gears. The lockup really does help but you really need to have three spare rear gears if you are planning on going all the way to the finals
     
    #21
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  2. TOL

    TOL Active Member

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    Mike, I'd like to ask a dumb question, and I really don't know the answer, so please don't shoot me!....

    Why is the "lock-up" hard on ring gears, assuming that a person is not un-locking and locking during a run (ie: no engagement banging)?
     
    #22
  3. jay70cuda

    jay70cuda Well-Known Member

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    It stretches the pinion out of the center. But who can afford that?
    Lock up with 5 speed and ecu $30,000
    Billet 10 in ring gears. $1000 per set
    Billet case with goodies $4000
    Carmac billet rear end assy $20,000

    and we haven't even started the car yet. They should outlaw these and make them for pro extreme only. It's taken the average racer who was competive with 3 speed stuff and forced him to sell or park it. 5 speeds will be the death of 1/8 mile racing. Pdra has been showing signs of it for 2 years now.
     
    #23
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  4. Austin Boil

    Austin Boil New Member

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    M&M Transmissions are what most all the guys who run a T400 are using with excellent reliability with high HP programs. You can get lockup or non-lockup. Mark Micke is also a very successful racer so he's continually improving or developing new stuff.
     
    #24
  5. blowntrifive

    blowntrifive Member

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    Blown Hemi with a Rossler TH400 3 speed. 34.5 tire and a 10" Ring gear we will see. had a three speed in my heavy street car for years with no issues other than RPM drop is the death of HP or Recovery!
     
    #25
  6. moparchris440

    moparchris440 Member

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    what rear gear and trans ratios you running
     
    #26

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