# springs



## sentra_hilo (Apr 23, 2003)

which springs are better for a b14 w/ kyb agx's. H&R or Eibach Pro-kit. which ride smoother. not planning on getting them any time soon. just wondering.


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## zeno (Sep 17, 2002)

Personally, I like the H&Rs but that is more of a personal opinion. Both are good springs, the only real difference is that the H&R will level the car out slightly more.


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## sentrapower93 (May 11, 2002)

I hear the H&R springs are a bit firmer than the pro-kits so there's less chance of bottoming out, plus they seem to level the car better than the Eibachs...


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## sentra_hilo (Apr 23, 2003)

so basically the H&R springs are stiffer for performance and eibachs are a lil smoother?


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## Skinny G (May 9, 2002)

H&R is stiffer because it is lower. Same full bump load. ST and Progress are stiffer than Eibach too, but they are lower as well. It probably won't make much difference which way you go as far as bottoming.


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## Wont Be Beat (Sep 20, 2002)

Skinny G said:


> *H&R is stiffer because it is lower.*


What a load of shit.


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## McLaren F1 2003 (Jan 2, 2003)

hahahahahahhahahahahahahahaahahahahhahahhaahhaha

but seriously, wont be beat is right


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## Skinny G (May 9, 2002)

Wont Be Beat said:


> *What a load of shit. *


Thank you for your kind words of wisdom and insight. But please inform me as to the reasoning behind this statment. Perhaps I am missing something.

My reasoning stems from this:

A spring manufacturer generally tries to make a set of OEM style springs that can handle the same load at full compression at the stock set. 

This load can be determined or compared by calculating (spring rate) x (travel). If I shorten the travel by a certain amount, the spring rate will have to go up in order to produce the same amount of load at full compression. 

All the springs I have seen that have higher rates than Eibach (Prokits or whatever amuses you), are also LOWER than Eibach springs. In order for these lower springs to work, they must have higher rates. In the end, they really aren't that much different from each other, as the full load on compression on the spring is the same, regardless of spring rate.

I look forward to hearing your rationale, in that same pleasantly informative manner.

G


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## Wont Be Beat (Sep 20, 2002)

So your saying that because a spring is lower, it must therefore be stiffer and have higher spring rates? This is incorrect. A linear spring, no matter how how compressed it is, will have the same spring rate for every measurement of travel. A progressive rate spring will not, however.

By your invalid statement, you also claim that lowered ride height inherently determines spring rate. I have skunk2 coilover on my car. I installed them this past weekend. I set the height to about 3/4 up the sleeve. When I brought my car down off the jackstands, the car was 6" higher than stock. I drove it and it was as stiff as I expected. Spring rates were linear. I then lowered the sleeves to desired height. Spring rates remained constant at the lower height as well.

The conclusion is that spring/ride height DOES NOT determine spring rate.


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## sentra_hilo (Apr 23, 2003)

ok this is going kinda in a different direction. i just wanted to know which springs ride smoother.


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## Skinny G (May 9, 2002)

You are completely misunderstanding me.

I am NOT saying that spring height determines spring rate.

I am saying that FOR a given ride height, the spring rates MUST be taken into account.

*A linear spring, no matter how how compressed it is, will have the same spring rate for every measurement of travel.*

Absolutely

*A progressive rate spring will not, however.*

Absolutely

*I have skunk2 coilover on my car. I installed them this past weekend.*

I'm sorry to hear that

*I set the height to about 3/4 up the sleeve. When I brought my car down off the jackstands, the car was 6" higher than stock. I drove it and it was as stiff as I expected. Spring rates were linear. I then lowered the sleeves to desired height. Spring rates remained constant at the lower height as well.*

Absolutely

Now lower them to 1/4" suspension travel, and tell me if maybe the spring rates _should be higher_ to handle the significantly reduced travel.

*The conclusion is that spring/ride height DOES NOT determine spring rate. *

Absolutely, in as much as the spring will not change it's rate. Keeping in mind that the original poster of this thread was inquiring about OEM style springs, NOT coilovers, if you pick a desired ride height, that height will determine what rate you should use.

Notice I did not say earlier "If I shorten the travel by a certain amount, the spring rate *will go up* in order to produce the same amount of load at full compression," I said "*will have to go up*."

_If a set of lowering springs do not come with increased rates, the car will bottom much more easily than if it were left alone. Therefore, the lower the car is, the higher the spring rates *will have to be* in order to prevent bottoming._

I am hoping that this is a bit more clear to you, as it seems that I lack some eloquence in my communication.

I look forward to hearing your effervescent response.

G


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## Skinny G (May 9, 2002)

sentra_hilo said:


> *ok this is going kinda in a different direction. i just wanted to know which springs ride smoother. *


Generally, a softer spring rate will be smoother, _however_, either spring will likely bottom out the same.

I would recommend running the taller of the two (the Eibach), and run soft (koni, or softened OEM) bumpstops to soften the bottoming.

I went from 156/152# Tokico springs in my B13 to 300/200# Hypercoils and the ride quality was not significantly different - but it bottomed a lot less with the higher spring rates.

G


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## Wont Be Beat (Sep 20, 2002)

In any case, getting springs with higher spring rates just to prevent riding on bump-stops is not the ideal solution. Dampening should be increased, and not spring rates.

Still, a statement such as, "H&R is stiffer because it is lower" is still incorrect whether you were erroneous in making it or not.

So to conclude, while your statement may be factual and even perhaps logical, it is not a technically correct solution none the less.


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## Skinny G (May 9, 2002)

You are the very first person I have ever found anywhere (in person, online, in print or in testing) who suggests increasing damping (not dampening - it has nothing to do with water) to reduce bottoming. How very odd.

It seems that you and I have a very different understanding of suspension design, operation and set up. May all your ideas work out for you.

Sentra_hilo, I hope you find the answer you are looking for, as I apparantly have my head up my ass.

G


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## Wont Be Beat (Sep 20, 2002)

I didnt say that. You have a point. As do it. I had Eibach Prokit which I hated because the rates were much to low and the drop much too large. My upper control arms would hit the inside of my shock towars. I now have Skunk2 coilover sleeves with much higher spring rates raised to near stock height and I'm in love.

Hitting bumps and bottoming out is due to a sudden change in suspension geometry. Sudden changes in compression are controlled by dampers and not springs. Springs help control body roll and ride height. They act as dampers only as a secondary system to the actual shocks. This is inherent in anything preventing any type of compression including swaybars, shocks, springs, etc. 

Dont be condescending.


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## bahearn (Jul 15, 2002)

Springs are the "shock absorbers" in the system. They also maintain front and rear ride height as well as roll control.

Dampers are strictly for control spring deflection rate and oscillation. They are NOT for preventing bottoming of suspension, that's a job for springs. If you're bottoming the suspension on a regular basis, your *springs* are TOO SOFT.

Sway bars are for *TUNING* roll rate, not total control of roll rate. A sway bar is only as good as the spring it works against. Soft springs and stiff sway bars still equals lots of roll.



> Hitting bumps and bottoming out is due to a sudden change in suspension geometry.


No. Suspension deflection causes geometry change. Bottoming out causes an instaneous and nearly infinite increase of spring rate but does't change geometry.


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## Wont Be Beat (Sep 20, 2002)

I guess its all in how you look at it. To me, the compression of a spring and the inherent camber change is a change is suspension geometry. See my point now?


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