offset rear axle?

Discussion in 'PSI Superchargers Tech Questions' started by vwsamba, Jan 29, 2021.

  1. vwsamba

    vwsamba Member

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    is there any good reason why a rear axle would be offset 1/2 to the right side on a funny car?
     
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  2. HootersFunnyCar

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    So you can run stagger for the turns o_O
     
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  3. vwsamba

    vwsamba Member

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    Its square in the car. Its a fabricated steel unit. When they welded on the floater ends the right side is 1/2 inch longer. Just checking to see if that's a thing before I tear it apart and correct.
     
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  4. Bob Meyer

    Bob Meyer Comp Eliminator

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    Depends on who built it and how good their fixture was. First thing to do is check the fat of the tire to the tin to see if it's the same. Second thing is, are you measuring correctly ? Pinion CL to Wheel mount
    face ?
     
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  5. kosky racing

    kosky racing Comp Eliminator

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    Bob I heard that certain pro mod builders put in what is called rear steer ----one side leading the other
     
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  6. vwsamba

    vwsamba Member

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    I'm measuring from the mounting plate to the end face of floater hub where the caliper mount bolts on. 4 inches left side 4 1/2 right side. Measured from inside of wheel face to frame also and its the same.
     
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  7. vwsamba

    vwsamba Member

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    This not rear steer. Its dead straight only the right wheel mounting face is half inch further out
     
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  8. vwsamba

    vwsamba Member

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    Checked pinion center to wheel face and its the same
     
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  9. Graham Brown

    Graham Brown Member

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    Don't rush into chopping it yet.
    Measure from the width C/L of the chassis/wheels at or near the front axle to each rear spindle hubs and see if they are the same size.
    The chassis could be off center or misaligned but the rear end is square to the front C/L.
    BTW it's a 1/4" off center.
     
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  10. vwsamba

    vwsamba Member

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    No I'm not rushing anything. There may be a good reason the right rear wheel is 1/2 further out than the left. I just don't know what it is.
     
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  11. Graham Brown

    Graham Brown Member

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    It could be someone's attempt to help balance the chassis torque reaction by moving the center of gravity off to left 1/4".
    Also check if the front crank C/L is central in the chassis or also off to the left 1/4".
    Not trying to be an expert here ...... just looking for discrepancies that might explain the outcome.
     
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  12. vwsamba

    vwsamba Member

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    Yes crank CL is centered.
     
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  13. Graham Brown

    Graham Brown Member

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    I'm lost now too.
    Try to do the rear end squareness check by doing my earlier measurement method ..... it may need the engine out though.
    If the two measurements differ and it's longer on the housing long side try measuring the length but to a point 1/2" inboard from where you measure to on the rear end.
    That's all I've got ..... good luck with it.
     
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  14. Mike Canter

    Mike Canter Top Dragster
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    How does the car drive? Does it go straight down the track with the offset in it?
     
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  15. Bob Meyer

    Bob Meyer Comp Eliminator

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    Story time........ one of the most famous front engine chassis builders of all time, (and a friend of mine) was sort of caught in this scenario in the sixties ! Two of the best T/F guys of the time were comparing their cars in the pits, one had 1/4" more tire clearance to the body on the left than the right! So the other guy goes to check his car and discovers the exact opposite !
    They both call the builder on Monday to ask why.........and the answer was identical, well of course you have to understand torque, load, twist, body weight, and the hypotenuse of the triangle, don't worry about it........click!
     
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  16. vwsamba

    vwsamba Member

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    new car to me but it has gone down the track fine from an outside visual perspective. i now see the left front is 1/2 further out too so i have to believe its intentional to somehow balance torque?
     
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  17. Graham Brown

    Graham Brown Member

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    LH front is 1/2" out and the RH rear is 1/2" out ..... doesn't that now make it a parallelogram".
     
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  18. Mike Canter

    Mike Canter Top Dragster
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    If it goes down the track straight then my recommendation is to leave it alone. Rear steer by offsetting the rear axle is done all the time in Promods instead of putting preload on the four link which can put them into a bind.
     
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  19. Graham Brown

    Graham Brown Member

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    Absolutely.
     
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  20. kosky racing

    kosky racing Comp Eliminator

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    read reply #5
     
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