Lower front suspension arms - what are the differences?
#32
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David,
Just saw your post and politics aside, I would politely suggest that someone somewhere has screwed up with that arm fabrication considering the following:
1. The arms are identical both sides. As I understand the optimal position for the arm when loaded under deadweight conditions with stock springs/spring rates is to have the arm horizontal thus identical arms can be used
2. The original fabrication [as I understand] on the front position has the rubber bonder to the outer support and the inner boss of the arm and is intended to flex with at a given spring rate to complement the rest of the suspension.
3. Once the arms have been bedded in, they should be retained in that position noting that the open bush at the rear takes a permanent set.
Considering the above I would say that if that arm has been refurbed to original specification then something is clearly wrong and the best thing you can do is contact whoever supplied those arms to enquire why you are experiencing what you have posted about just in case they know something better than I do. They may advise it is ok to fit them and that they will take an acceptable permanent set with use but what I see on your photo would definitely concern me based on the studies I have made of the system design. If the revamp of the arms does not have the rubber bonded then maybe they can move appropriately during the settle in period but if that were the case then such should be mentioned in the instructions that came with the arm.
On the second point not sure I fully understand what you are saying but the ball joints as I received and fitted from Roger were identical for what that may be worth. .
Just saw your post and politics aside, I would politely suggest that someone somewhere has screwed up with that arm fabrication considering the following:
1. The arms are identical both sides. As I understand the optimal position for the arm when loaded under deadweight conditions with stock springs/spring rates is to have the arm horizontal thus identical arms can be used
2. The original fabrication [as I understand] on the front position has the rubber bonder to the outer support and the inner boss of the arm and is intended to flex with at a given spring rate to complement the rest of the suspension.
3. Once the arms have been bedded in, they should be retained in that position noting that the open bush at the rear takes a permanent set.
Considering the above I would say that if that arm has been refurbed to original specification then something is clearly wrong and the best thing you can do is contact whoever supplied those arms to enquire why you are experiencing what you have posted about just in case they know something better than I do. They may advise it is ok to fit them and that they will take an acceptable permanent set with use but what I see on your photo would definitely concern me based on the studies I have made of the system design. If the revamp of the arms does not have the rubber bonded then maybe they can move appropriately during the settle in period but if that were the case then such should be mentioned in the instructions that came with the arm.
On the second point not sure I fully understand what you are saying but the ball joints as I received and fitted from Roger were identical for what that may be worth. .
#33
Burning Brakes
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Hi Fred
Yup I think the refurb is off but managed to fit the arm and twist with a bar without ripping any of the bonded section....I think. I will get it rolling and see.
As to ball joints yes they are the same. Dry fitting and thinking about it the asymmetry is ok (I think) because the slot in question adjusts camber...
Will try to load some images of the assembly if I can get wifi to play ball
D
Last edited by C531XHO; 08-26-2018 at 11:52 AM. Reason: add image
#34
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Hi Fred
Yup I think the refurb is off but managed to fit the arm and twist with a bar without ripping any of the bonded section....I think. I will get it rolling and see.
As to ball joints yes they are the same. Dry fitting and thinking about it the asymmetry is ok (I think) because the slot in question adjusts camber...
Will try to load some images of the assembly if I can get wifi to play ball
D
Yup I think the refurb is off but managed to fit the arm and twist with a bar without ripping any of the bonded section....I think. I will get it rolling and see.
As to ball joints yes they are the same. Dry fitting and thinking about it the asymmetry is ok (I think) because the slot in question adjusts camber...
Will try to load some images of the assembly if I can get wifi to play ball
D
Just remember that the bush material follows Young's law just like any other material and whereas I have no doubt it can be manipulated into position the question that needs to be asked is whether the degree of rotation needed can ultimately damage the bushing- for sure I do not know the answer to that. Additionally, as a spring that is over extended, would that additional reactive force compromise the suspension response to any meaningful extent?- I doubt it but...?
Rgds
Fred