To make things easier to explain, i've added a little picture... just use your imagination... and I don't actually know the proper terms, so please bare with me.



On a fully threaded shock body:
A: Spring
B: First collar (spring perch/preload)
C: Second collar (locking collar)
D: Third collar (locking collar)
E: Lower shock mount (adjustable)


I have a set of coilovers that allow you to adjust the height by the Lower Shock mount (E) by un/screwing the shock body into it. As well as allowing you to move the First collar (B) to set where the spring perch is.

I have inititally set up the unit such that I preloaded the spring by raising the First Collar (B) until the spring made contact with the top of the shock and the First collar, and then giving it 4 full turns. And the lower shock body has been screwed into the lower shock mount (E) until it could not go any further.

If I was to lower the car even further, I could only do this by lowering the First Collar (B). If I lowered this more than 4 turns, wouldn't the spring be not preloaded (unloaded?)? If I lowered it a large amount to the point where the Spring (A) was at full expansion and only made contact with the first Collar and no longer touched the top of the shock, couldn't this be a potential for failure? Wouldn't the spring be "floating" around, able to move up and down if the shock was at full expansion?

I just don't understand how safe that can be when people are saying they are "slamming" their cars. If I lowered the first collar until it met with the third collar, I'd have tons of play between the top of the spring and the top of the shock allowing the spring to go whichever way.

hypothetically, if I hit a large pothole, and the shock became fully uncompressed, and the spring could bounce around, could it "unseat" itself and get lodged skewed?

Or is this the way they were designed? To slam the car you lower the perch and have the spring sit further down and then when the shock is compressed you lose shock travel because the shock is already compressed at neautral a position (the way the shock sits when no additional compression is applied to it)? And you would never have any preload set in these sorts of setup?

 

Once you do this you're as low as you can go (just like the song says). The two adjustments (height/preload) are seperate of each other, keep tension on the spring with the spring perch, supposed to be just enough so the spring can still spin. I do a couple more turns if they're freshly installed

 

If you cannot have both a pre-load on the spring and the lowering that you want, then you should add a helper spring to keep the spring lined up with the perch and hat when unloaded.

 

in the image you inserted, you mentioned that E is adjustable? why not adjust it from here and leave everything else.

 

yeah I did do that, the lower shock mount has been threaded as far as it will go.

I've only added 4 turns to preload the spring. In the above posts, I'm told that's as low as you can go now, without adding helper springs. Is that what helper springs are used for? I thought they were for making the suspension softer and make the drive more tolerable.

 

The purpose of a helper spring is to keep things lined up if and when the main spring becomes completely unloaded at droop. Helper springs are not intended to play any role at all in actually suspending the car. Unless the car is at near-full droop, helper springs are always squashed complete flat and, therefore, have no effect on ride or anything else.

I don't know if there's a name for a second, softer spring that is intended to play a role in suspending the car. Usually, when you want a progressive spring-rate, you buy a single spring that is wound to be progressive (by having some coils closer together than other coils).

 

What brand of coilovers are you running?

 

Good info here. ^^^

You're referring to a "tender spring". Some people run a tender spring with their regular spring to have a progressive spring setup. It's an alternative to having custom progressive springs wound.

OP: At this point, you've got 2 options to go lower without buying new coilovers. The 1st is going to be a helper spring. Even with the helper spring you won't be able to go much lower without risking damage to the shocks. I'd go no more than 1/2" lower. Your next option is a last-ditch effort in my opinion, and you should only do it if you don't care about handling, ride quality, etc. You can always call whoever makes your coilovers and ask them for a shorter shock. I wouldn't do it, but it is a possibility for you.

 

Thank you! My memory stinks, but as soon as I read that, it came back. (I did some things in the 1970s that really did some damage to my memory, but we need not go into that in any detail.)

For anyone wondering what we're chatting about - no, not the 1970s; I'm now back to the issue of helpers and tenders - here's a good link: http://e30m3project.com/e30m3perform...ings/index.htm

 

That's an awesome article. I'll have to keep that bookmarked in my "Rad articles to post, so I don't have to type essays" folder

E30 + M3 = High on my short list of BMWs I would ___________ for.

 

Just curious as to what brand/model coilovers we are talking about here....

 

Should probably also ask the OP if he has fixed his roll center....

 

I'm running the HSD HR coil overs. and I'm pretty happy with them. they do the job and still give a good comfortable ride since this is a daily driver. they have also been wife approved!

and no... I haven't fixed my roll center.

I don't really wantto drop the car any lower. I'm happy with the ride height. I was just wondering how it works when people "slam" their car. my friends have told me they adjust the height of their coilovers by lowering the spring perch and I asked them if it their springs still touched the top and the perches and if that was right/safe if it didn't. they all told me that's how they did it.

I just wanted some clarity. if lower it anymore it won't be by very much. maybe half an inch as suggested. right now I have no fender gap in the front or rear.

 

If you have no fender gap, then you either have really large tires or you need to fix your front roll center (assuming that you don't race under rules that don't allow it).

 

win!!!