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Automatic trasmission and rear axel

  1. Nov 21, 2006 #1
    i have a v8 350 carburated vortec motor and a automatic trasmission th700r4 4 speed , i want to know which one rear axel i get more displacement when the car to go in high speed, because with the actual rear axel it feeling forced, the rear axel have a gear crown inside 42 grooves. and i want to know how to do to the lock up or overdrive works in automatic way.

    o_emanuels@yahoo.com thanks for help

    tengo un motor v8 350 carburado montado en un malibu 81 con una trasmision th700r4 4 velocidades pero en alta velocidad se queda con falta de desplazamiento debido al diferencial trasero, arranca con mucha potencia pero en alta se queda, yo quisiera mas desplazamiento en alta, mas desarrollo, la corona interna del diferencial tiene 42 ranuras. y tambien quisiera saber como hago para que el lock up o overdrive trabaje de forma automatica

    o_emanuels@yahoo.com gracias por la ayuda
  2. jcsd
  3. Nov 21, 2006 #2


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    Gold Member

    Welcome to PF, Omar. Unfortunately, your wording is very difficult for me to understand. And despite having Spanish blood, I can't communicate in that language.
    If I understand correctly, the response is that the steeper that axle ratio is, the faster you will accelerate. A shallow ratio will give slower acceleration, but a higher top end.
    For example:
    If your car (even with that itty-bitty baby motor :biggrin: ) can run 13 seconds and top out at 100 mph in a quarter mile and continue on to 120 mph in the long run with 3:23 gears, swapping down to a 4:56 axle might give you 11.5 at 110 mph in the quarter, but your top speed will be only that 110 mph.
    Those are just 'for instance' figures, not something that I worked out mathematically. Still, that's the essence of how the axle ratio affects performance.
    You should really have a conversation with Stingray about this.
    Last edited: Nov 22, 2006
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