Need Alignment Help!

Hopefully this makes sense:

Imagine looking from the front of the car at the suspension



This is a very simple illustration but shows why I want to get it right. I really don't know what ideal is but I believe the factory "static" setting is it. To really understand how big is big I would need to study the actual control arm travel and the hub camber change. I don't really have the time for that now.

Just another point the dimensions I measured are the spring and also the spring perch and isolator thickness. I need to know the complete stack up. For the spring perches I had turned they have a thinner flange so I reduce some of the total stack up and the control arm moves that bit closer to the ideal position.. I hope that clears up what I was after.


The stiffer spring is common for lowered cars and for hitting a specific wheel frequency (check out wheel rate if you are not familiar). In this situation the heavier spring limits the amount of suspension travel, the shock manages the how quickly the suspension responds. The trade off is a harsher ride. For a given load the spring will compress only so much. That is important because the change in camber and toe is minimal because the jounce/rebound range is small - softer spring will have a larger jounce and rebound range. I know this is lots of random info but it does all come together. I know I did not answer all your questions but I will try to address more tomorrow.

The thing for me is I don't know this car that well and it is best to get the input from other owners. They have been around for along time and I don't want to make too many assumptions ans reinvent the wheel. Your help and info has been very, very helpful.

[johnb]

Look up Roll Couple (unless you are familiar with it already) and that should give you an idea of what I am after.

As I said previously, my knowledge on this subject is limited so not familiar with Roll Couple. Some more Internet research and now have a bit more insight into the effects this has on the way a car corners.

Yes my conclusion is the Spax/Eibach kit is not sized to meet the designed suspension specs. Normally an adjustable shock allows the opposite problem where the car can be lowered too much and the suspension geometry goes out of whack. This is a first for me where the shock will only raise the car.

Hope that a solution is eventually found.

One one final point in the spring calculations it considers the raw steel diameter so you have to subtract the coating from the calc - yes I got some odd numbers at first and after looking at it with a buddy we figured that one out. We estimated the coating to be about 0.3mm, it could be more or less. It is a guess really.

Agreed, makes perfect sense.

[johnb]

This is a very simple illustration but shows why I want to get it right. I really don't know what ideal is but I believe the factory "static" setting is it. To really understand how big is big I would need to study the actual control arm travel and the hub camber change. I don't really have the time for that now.

The diagram does exaggerate the situation but understand why you don't want the car jacked up higher than it was originally.

Just another point the dimensions I measured are the spring and also the spring perch and isolator thickness. I need to know the complete stack up. For the spring perches I had turned they have a thinner flange so I reduce some of the total stack up and the control arm moves that bit closer to the ideal position.. I hope that clears up what I was after.

That explains it, previously I thought you were only referring to spring lengths.

The stiffer spring is common for lowered cars and for hitting a specific wheel frequency (check out wheel rate if you are not familiar). In this situation the heavier spring limits the amount of suspension travel, the shock manages the how quickly the suspension responds. The trade off is a harsher ride. For a given load the spring will compress only so much. That is important because the change in camber and toe is minimal because the jounce/rebound range is small - softer spring will have a larger jounce and rebound range.

Yes, I appreciate the effects of wheel rate from recent education from the internet.

The thing for me is I don't know this car that well and it is best to get the input from other owners. They have been around for along time and I don't want to make too many assumptions ans reinvent the wheel.

Two heads (or more) are better than one so obviously makes sense to seek input from others who may have followed the same path. A310s are, I presume, scarce in this country so perhaps not many have had suspension modifications from which feedback might have been given. It would be good to be proved wrong.

OK here is the update

1) The original toe issue was resolved by cutting the threaded end on the tie rod ball studs (getting the car to static position made little if any change to the toe)

2) The SPAX/Eiback kit will work but the car will be 25mm-30mm higher than the stock static position

3) I modified the front shock and spring to get the car to static position and all seems to be working great



Toe issue:















SPAX/Eibach Installation Points:





Modified Suspension - Static Height Setting

[johnb]

Interesting summary Brian.
Perseverance can bring results. Good to see that you've sorted the problem.

Hey John,

Yeah the quest was a bit up and down and all over the map but I am content with the outcome. My initial problem of trying to solve the toe was due to what I would call a part defect with a long threaded ball joint. 99.99% Of the people would have just trimmed off the end from the gitgo and been done with it but I am one of those guys that has to investigate it and understand all the details to assure there isn't another underlying problem. No matter what I would have gone through the exercise down the road when I wanted to lower the car so it has not been a wasted effort.

I would like to give a hearty thanks to you for your assistance. You have quite a bit of technical stuff I don't have so the information you have provided has been added to my Alpine technical library. The static setting jig / gauge was a key piece of information.

So after all the commotion and stir the car drives nothing like I expected. I thought it would be more race car like, tight and skittish. My car anyway, is fairly soft and tame. I have yet to really try to throw it around but I was starting to push it around turns and it was pretty docile. I suppose that is a good contrast to my Fiat. Over the winter I will be addressing the remaining technical issues and will post them on the site. Some issues will seem goofy and trivial but I will dig deep so I can make an informed decision. Once mechanically sorted I can move to paint and finish.

Regards,
Brian

[johnb]

Yeah the quest was a bit up and down and all over the map but I am content with the outcome. My initial problem of trying to solve the toe was due to what I would call a part defect with a long threaded ball joint. 99.99% Of the people would have just trimmed off the end from the gitgo and been done with it but I am one of those guys that has to investigate it and understand all the details to assure there isn't another underlying problem. No matter what I would have gone through the exercise down the road when I wanted to lower the car so it has not been a wasted effort.

Must admit that with my car I followed some investigation paths that, with hindsight, could have been shortened but I learnt things along the way that wouldn't have been learnt otherwise.

I would like to give a hearty thanks to you for your assistance. You have quite a bit of technical stuff I don't have so the information you have provided has been added to my Alpine technical library. The static setting jig / gauge was a key piece of information.

Glad to have been able to help in a small way. Feel free to click the thumbs up icon on anyone's posts.

So after all the commotion and stir the car drives nothing like I expected. I thought it would be more race car like, tight and skittish. My car anyway, is fairly soft and tame. I have yet to really try to throw it around but I was starting to push it around turns and it was pretty docile. I suppose that is a good contrast to my Fiat.

I can only describe my car as 'planted' with minimum roll in corners. The suspension is firm but not hard and it's certainly not skittish.

Over the winter I will be addressing the remaining technical issues and will post them on the site. Some issues will seem goofy and trivial but I will dig deep so I can make an informed decision. Once mechanically sorted I can move to paint and finish.

Hopefully finished and useable next year then.

Hey John, I don see where I can put that icon cept here ; Where am I supposed to tag it so it will register as a thanks?

[johnb]

Hey John, I don see where I can put that icon cept here ; Where am I supposed to tag it so it will register as a thanks?

I've just logged out to see if it was a member-only feature. The icon disappears when logged out so that's why you can't see it. Never noticed that before.
No matter, it was only a tongue in cheek remark.