Front suspension arm design discussion

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milnet
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Front suspension arm design discussion

Post by milnet » 06 Jan 2015, 16:25

Im planning out the front suspension arms in my head and I'm looking for the best\proven designs to steal from. I would like to use OEM-style upper and lower ball joints, I like the nascar style upper a-arm for its simplicity and proven track record. I want to be able to adjust camber and caster but I don't mind taking off the suspension arm to adjust it.

Here is what I'm talking about - NASCAR Front Upper Control Arm - I would use spherical ball-ends on the chassis side.
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This part is newly available - Moog "Problem-Solver" Upper control arm ball-joint;
viewtopic.php?f=13&t=623
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Lower ball-joint is same as the book - http://www.moog-suspension-parts.com/pr ... MOOG-K9908 -

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For the lower arm I was thinking of copying this design but replacing the chassis joint with a 5\8 ball joint mounted with the bolt in the horizontal position as-per the books notes. (Maybe use something larger on the bottom, I like how beefy these arms look and I believe Vorshlag used 3\4 rod-ends in these arms) I plan to implement the use of the solid a solid rod end at the ball-joint end of the arm.

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Credit - Vorshlag Miata LS1 Alpha project - http://www.vorshlag.com/forums/showthread.php?p=58021

Midlana1
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Re: Front suspension arm design discussion

Post by Midlana1 » 06 Jan 2015, 17:31

As long as the six pivot points don't move, you can do anything you deem safe.

bgkast
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Re: Front suspension arm design discussion

Post by bgkast » 06 Jan 2015, 19:11

I had the same idea, but found that you will need to modify the Miata upright to accept a screw in ball joint like the nascar ones. There has been considerable time spent looking by folks on the locostusa forum, but no screw in upper ball joints have been found that fit it . I ended up using a Moog ES2074R tie rod end as an upper ball joint. It fits the upper part of the Miata upright with no changes. See my thread here: viewtopic.php?f=14&t=547&start=20

Edit: It looks like that Moog problem solver ball joint you posted is a replacement for the typically non-replaceable Miata upper joint. It looks like a press in joint, not a screw in like the nascar joint, but it should work similarly, you will just need to machine a cup that fits. The only problem I see is if they stop making them you are outta luck, so stock up. :D

milnet
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Re: Front suspension arm design discussion

Post by milnet » 06 Jan 2015, 21:39

bgkast wrote:I had the same idea, but found that you will need to modify the Miata upright to accept a screw in ball joint like the nascar ones. There has been considerable time spent looking by folks on the locostusa forum, but no screw in upper ball joints have been found that fit it . I ended up using a Moog ES2074R tie rod end as an upper ball joint. It fits the upper part of the Miata upright with no changes. See my thread here: viewtopic.php?f=14&t=547&start=20

Edit: It looks like that Moog problem solver ball joint you posted is a replacement for the typically non-replaceable Miata upper joint. It looks like a press in joint, not a screw in like the nascar joint, but it should work similarly, you will just need to machine a cup that fits. The only problem I see is if they stop making them you are outta luck, so stock up. :D
I have a lathe and access to a bigger one, also have access to a CNC mill. I was thinking of making a cup with a thread on cap to hold the ball-joint in place from above. I already ordered the Moog problem solver joints so I can model it up.

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