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Snoogins gave a detailed and accurate answer. We have talked about this since the dawn of the internet.

I'll simplify: Only a rich dope gets a adj coilover for a street car. I use them with a borrowed set of scales for autocross (sp). If you do not use scales you will probably make you handling WORSE.

The vast majority of advertised spring rates are either flat-out false or guesstimates done without checking (Lol, what's a spring tester?).

BTW, don't know if I'd agree with your statements about adjustable coilovers aren't necessary for a street car. They aren't a competitve only purchase, as anyone with a desire to set and adjust height to their liking (as opposed to preset perches) will want them, or someone who wants to say make adjustments to height seasonally. Coilover height adjustment can be done while on the car, while springs+shocks generally require removal and reinstallation of the suspension.

Also, there is indeed something called a spring tester that will "dyno" a spring and tell you the actual rate. In fact, when I buy my hypercoils, I get both the manufacturer's rate and the actual rate as the shop has tested them (e.g., my 1200lbs springs were dyno'd at 1211 and 1203lbs). Its handy if you really want to know what you're getting, though its also more common with linear springs than progressive (note also that spring rates quoted for progessive springs are generally quoted at the max rate).

load variation at the test height? Or is that what you were testing? Please elaborate on the testing procedure. This sounds like nice equipment.

My (linear) spring rates are simply the amount of force it takes to compress the springs 1". It's a linear equation (spring rate = force/spring deflection).

You can get cheap tester to measure a springs rate (companies like Longacre/Intercomp sell a basic portable hydraulic one for under $5-800, though manufacturers and probably your bigger race teams use more accurate computer equipment).

According to Hyperco, they can generate accurate graphs and tables of spring load per unit deflection in increments of 0.1in (2.5mm) from free length to solid stack. Hypercoil guarantees within 1% accuracy of the advertised rate, btw.

One of the reasons a spring company can guarantee RATE is that it is dependant upon wire diameter, coil diameter and number of active coils; all mechanical things which don't change. What isn't always constant is the load at a given compression. This determines your ride height in a non-adjustable setup, and can change or sag with use.

BTW, when you check your rate, do you first compress the springs to solid 1 or 2 times prior to testing? How accurately do you measure the 1 inch? For the numbers you quoted, you need to be accurate within about +/-.001 in.

Are you really using 1200 lb/in springs on an A/S4?.

I'm not the one doing the testing. Hyperco tests them (in batches I presume), and the shop I buy them from verifies. On the spring itself, you'll see an etched rate of say 1000 from Hyperco, and separate sticker from whoever tested with the actual, say 1009. Most reputable suppliers can provide you a print out with the specific dyno info and coil specs. I don't have a spring tester in the garage :-). But I believe you have to apply load to the spring at the design length (compressing 1/2" or so) and then move 1" from there to get the rate.

I believe most commercial spring testers are indeed calibrated to .001" (at least Hyperco does per their site). I think Eibach says the same; I suspect that is an industry standard.

I have a few different springs sitting in my garage for my S4 varying between 700-1300lbs. What's on the car right now is 800F/1200R.

It comes up all the time because people like you (the original poster, not Sharon the racer) are too lazy to do any research on your own. Then you want some kind of pithy answer that supports your preconcieved answer.

Adj. coilovers on a street car are for poseurs who know nothing about handling, but like the look.

It is not a cost issue. You can make your own kit from GC or Carrera for cheap. It is a handling issue. You will find it almost impossible to gain any statistically significant improvement over a quality set of fixed height coilovers.

This is true even if you bother to get it set up on some scales (the vast majority of poseurs don't). What F:R % are you going to use and why? Tell me that and you prove you are not a poseur.

Scales are the first step, but what are your roll centers front and rear? Why? Which rates are you using? Why? What is your compression damping on your shocks? Why?

Coil "dyno" is a classic moron statement. A coil spring tester (as I described in my first post) is not a dynanometer. But poseurs have learned that the word dyno is cool.

They check many points to get the rate, BTW.

And we wouldn't want to piss off the cranky people who have to time to troll the boards looking for posts to rag on, but not the time to just skip over threads that are uninteresting to them.

Chips, spring rates, dyno debates, oil weight, can an A4 take a..., all come up and will keep coming up. Audience changes, people come and go... whatever. Skip the post.

Seems like Sharon, (who never comes off like an idiot as far as I can tell) put "dyno" in quotations to calmly make the point that rate tester isn't a dyno.

I've met many non poseurs with coil-overs. Some know more about handling set up than others. Some are just using them to adjust ride height easily for seasonal driving condition changes. But hey, you know more than Sharon the subject, right?

But I'll stop. It's all been said before.

to check the archives, I am going to get on them.

Sharon is not the issue. She's a smart, INFORMED, person. If she doen't know something, she figures it out.

She is the polar opposite of the wannabe posuers that has taken over the board. The person in question got a very detailed, accurate response, and several good summaries from folks. He then posted in that thread that he essentially couldn't care less about all the points that posters made. (None of which were mine.)

The he came over to this forum and ASKED FOR MORE COMMENTS! I gave him more comments. He just doesn't like the answers that he is getting.

If you don't like what I write, don't waste your time reading my posts.

a spring tester <b>is</b> a dyno!

Here is a definition of a dynamometer:

Dynamometer \Dy`na*mom"e*ter\, n. [Cf. F. dynamom[`e]tre. See Dynameter.] An apparatus for measuring force or power; especially, muscular effort of men or animals, or the power developed by a motor, or that required to operate machinery.

Note: It usually embodies a spring to be compressed or weight to be sustained by the force applied, combined with an index, or automatic recorder, to show the work performed.

So 4kq, before you go ripping someone apart for using a term improperly maybe you should know that they were indeed using it properly.

If people didn't ask the same questions over and over then Jason Teller might as well close up shop. Every forum you go to the same questions are asked over and over and over again. This is NORMAL, either live with it or move on.

By posting the info on spring rates, I was not intending to say that a person should buy one type of suspension vs another. I was not saying that coilovers were better than a spring/shock combo. I don't know why you are assuming this.

My intention was only to post a comparison of different companies' spring rates. I *did* search the archives. It just seemed as though the info the searches were turning up was not consistent. I then took it upon myself to start calling up each manufacturer and asking them.

For this reason I take offense to you calling me too lazy to do my own research. Research is exactly what I am doing. Perhaps my original post was a bit premature, for I had not yet obtained all the spring rates I was after. Over the last few days I have compiled much more complete information, and I was intending to post it here just for people to reference. I simply thought it might be handy to have a general reference of spring rates *as stated by the manufacturers.*

Sure, the manufacturers could be lying to me, or they could be wrong. There's nothing I can do about that. I apologize if you are aggravated by my post. I did not intend to cause you so much strife.

I thought there might be some people on this forum who might be interested, so I simply linked to the original post on the other forum. I created this crossposted link immediately after I made the original post on the other forum. I don't know why you are asking "Why post this here after it was discussed in detail there?" I did both posts within seconds of each other, so there was *no* discussion yet when I did the link.

Cross-linking to posts between forums is common practice, and is only meant to expand the audience, as not everyone reads every forum. I apoligize if this, too, has caused you aggravation.

Can't skip your posts, however zain.

thread first and started the second discussion? Maybe 4kq ought to complain to that poster.

Main Entry: dy·na·mom·e·ter
Webster
Pronunciation: "dI-n&-'mä-m&-t&r
Function: noun
Etymology: French dynamomètre, from Greek dynamis power + French -mètre -meter
Date: 1810
1 : an instrument for measuring mechanical force
2 : an apparatus for measuring mechanical power (as of an engine)
- dy·na·mo·met·ric /-mO-'me-trik/ adjective
- dy·na·mom·e·try /-'mä-m&-trE/ noun

You are absolutely correct. In the early 1800's with the development of consistant machining and winding practices, any equipment that tested "force" was called a dynanometer.

Today however, we call the vast majority of those simple instruments "scales" and the complex instruments (chassis and brake dyno) dynanometers.

Would you go to the butcher and ask him/her to dyno a pound of meet for you? Not for the last century and a half.

if it could cause some trouble than dropping to the ground heading towards the center of the earth then there should be a dynanometer for that

two different instruments. If you wanted to know what the spring weighed, then use the meat scale, but if you want to know the springs weight capacity, then use a spring dyno.

the way to recovery.

"Note: It usually embodies a spring to be compressed or weight to be sustained by the force applied, combined with an index, or automatic recorder, to show the work performed."

Sounds like the precise definition of a scale to me.