View single post by Jensenman
 Posted: 03-21-2009 02:46 am
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Jensenman

 

Joined: 04-14-2005
Location: Columbia, South Carolina USA
Posts: 156
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The Miata/MX5 knuckle is a much thicker and stronger piece than the J-H and there is a whole world of brake upgrades for it, not to mention the vast amount of aftermarket wheels for the 4x100mm bolt circle. The knuckle's height from end to end is within 1/8" of the J-H piece. The upper ball joint taper and OD are the same as the J-H, but the kingpin inclination is about 1 degree steeper meaning the upper ball joint has to move inboard to compensate. The lower ball joint stud is about twice the size of the J-H item, I found a Moog ball joint (K8286, originally for a Ford Taurus)) that fits the Miata knuckle and requires minimal modification of the J-H lower control arm. The stock Miata outer tie rod ends can be retapped for 1/2-20 and then threaded onto the original steering rack. The inner tie rods have to be shortened 5/8" to allow for toe adjustment.

BTW, on the inner tie rod subject: I have an extra rack I am going to disassemble to see if there is a way to tighten up worn inner sockets or if there is a readily available replacement.