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Thread: Control arm question

  1. #1
    3,000 rpm - starting to feel the power BRGNA8's Avatar
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    Control arm question

    Hey guys

    Just wondering would a full NB8 control arm set be a direct replacement for the NA8 chassis? If not, are there any parts which can be considered to be interchangeable?

  2. #2
    4,000 rpm - entering the fun zone RustRat's Avatar
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    Don't quote me on that, but in order to install NB control arms in an NA, you will need also the subframes, and then the steering rack from the NB too. And I am not too sure if the suspension will need tweaking after that, too.


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  4. #3
    6,000 rpm - mere mortals would shift JamieH's Avatar
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    You can swap the control arms without the subframes. But what you will need for the front is NB knuckles. The upper control arm ball joints are different between the two. If I have it right, the NB UCA ball joints have a larger taper than the NA UCA ball joints. So, without the knuckles, you won't be able to get the castle nut far enough down to slide in a cotter pin.

    I've seen no info that says you can swap just the ball joints either. Also, the MOOG replacement upper ball joint for the NA is only for the NA according to MOOG themselves.

    Beyond that, the NB arms from what I have read are a little stronger (and heavier) from internal stiffening and the front lower uses a different sway bar mount. There's not a strong argument for swapping to NB arms in an NA if it's a street car with little to no track/autoX use. I mean, maybe if you were trying to swap to lower mile arms for the bushings and ball joints on the cheap and that's what ya had access to, I could see it being worth the swap. That, or you just had to, like an unreasonable need, have every possible mechanical update/upgrade, regardless how small or minor, that the NB received in your NA.

    Apparently all of the improved front suspension geometry of the NB is in the front subframe. Which, to swap that into an NA requires the NB steering rack from the rack itself to the NB universal joint that splines onto the steering column shaft. The splines on the rack side of the U-joint are different, but they are the same on the column side.

    As to why it's worth swapping to the NB subframe and steering rack? That improved suspension geometry and a quicker ratio steering rack.

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