bensonae Posted January 25, 2005 Share Posted January 25, 2005 Are there any good pro rate springs that are out for the -05 legacy gt-and any suggestions on a good way to firm up steering feel. Link to comment Share on other sites More sharing options...
GBY Posted January 25, 2005 Share Posted January 25, 2005 Moved to Suspension/Brakes. Link to comment Share on other sites More sharing options...
RaceComp Engineering Posted January 26, 2005 Share Posted January 26, 2005 What do you mean by pro rate springs? Link to comment Share on other sites More sharing options...
Xenonk Posted January 26, 2005 Share Posted January 26, 2005 progressive spring rates.. meaning as you compress the spring more, the spring rate increases.. normally you can see it in a spring design (the coils either get wound closer OR the coils get thicker). I know quite a bit of companies out there, but why would you want progressive? You can try a set of Espelir springs (aka Mackin Industries) or some other JDM company as I dont know many companies that offer Progressive on the Legacy.. most are linear which gives the car a more predictabile feeling. What are you trying to achieve by using progressive?? Or is just an Eibach thing you are trying to avoid? Progessive (wound tight) http://www.mackinindustries.com/graphics/ESPELIR/activesuperdown.jpg Progressive (different diameter ends) http://www.mackinindustries.com/graphics/ESPELIR/activegt.jpg Linear http://www.endlessusa.com/products/categories/ico9.jpg Keefe Keefe Link to comment Share on other sites More sharing options...
RaceComp Engineering Posted January 27, 2005 Share Posted January 27, 2005 progressive spring rates.. meaning as you compress the spring more, the spring rate increases.. normally you can see it in a spring design (the coils either get wound closer OR the coils get thicker). I know quite a bit of companies out there, but why would you want progressive? You can try a set of Espelir springs (aka Mackin Industries) or some other JDM company as I dont know many companies that offer Progressive on the Legacy.. most are linear which gives the car a more predictabile feeling. What are you trying to achieve by using progressive?? Or is just an Eibach thing you are trying to avoid? Keefe That's not exactly what I meant, but run with it. Link to comment Share on other sites More sharing options...
Jaxx Posted January 27, 2005 Share Posted January 27, 2005 linear springs have no place in a road car unless you have helper springs all the springs that i know of for the legacy are progressive Link to comment Share on other sites More sharing options...
CRAZY KEN Posted January 28, 2005 Share Posted January 28, 2005 ...someone is challenging Keefe on knowledge of springs!!! Here we go!!! CRAZY KEN Link to comment Share on other sites More sharing options...
RaceComp Engineering Posted January 28, 2005 Share Posted January 28, 2005 What do you mean by pro rate springs? I knew that he meant by Pro-rate, but my new guy, JEFF did'nt quite understand the way it was put. Myles Williams Link to comment Share on other sites More sharing options...
Xenonk Posted January 28, 2005 Share Posted January 28, 2005 linear springs have no place in a road car unless you have helper springs all the springs that i know of for the legacy are progressive helper springs are there to allow lower ride heights without having to preload the spring (helper springs are just there to keep the main spring from getting 'airborn' and not seat properly when the load is off of it)... and from my knowledge, only a few selected springs are progressive for the legacy... I believe the STi pink springs are linear the last time I checked on the manual. Keefe Keefe Link to comment Share on other sites More sharing options...
Jaxx Posted January 28, 2005 Share Posted January 28, 2005 helper springs are there to allow lower ride heights without having to preload the spring (helper springs are just there to keep the main spring from getting 'airborn' and not seat properly when the load is off of it)... yup and the progressive coils do the same thing Link to comment Share on other sites More sharing options...
iON Performance Posted January 28, 2005 Share Posted January 28, 2005 bensonae - Our Sport Spec springs for the BL/BP are progressive in the front and linear in the rear. Lowering is 30mm (1.18" front) and 25mm (1" rear). Drop us a line if you're interested. Link to comment Share on other sites More sharing options...
Xenonk Posted January 28, 2005 Share Posted January 28, 2005 yup and the progressive coils do the same thing Unfortunately, I have to disagree. Progressive springs are wound in and designed in a way that the spring rate compression curve is parabolic, not linear. As the progressive spring gets compressed, the spring rate increases to resist binding or compression, so as the spring goes into compression during travel, the springs are going to have more and more lbs/in until its maximum designed limit. This can be a catch 22. It's more helpful in braking and acceleration as the compression flatens out the suspension travel curve to give the tires more time react to a smoother application of downforce. During decompression, the spring will "weaken" it's ability to bring the car back into normal (strong compression resistance, weak decompression assistance) static state, in other words, there's a longer wait for the car to settle for transistions. A good spring design-engineering will eliminate some of this "bounceback" of the spring by how the set of springs will work together, otherwise it can be annoying to drive a "boat" where the spring is fighting against each other to find an equilibrium. Road race cars use more of the linear design because most of the time, you want the car to have a consistent feel from the beginning of the compression stage all way through the corner-exiting balance. Linear springs will give the car a more predictable feel to the entire car in most driving environments. For you tech-geeks, I'll give you an example of the difference: Let's just say that the total overall suspension travel we are dealing with is 2" to make this easier to analyze. Progressive Sample (Spring 'A') has a minimum spring rate of 150 lbs/in and a maximum of 500 lbs/in when binded (when the spring is fully compressed, normally the advertised or targeted spring rate by design) Linear Sample (Spring 'B') has a constant spring rate of 500 lb/in. When the car is braking, under the first 1" of suspension travel, Spring 'A' will feel soft at first and there will be more head diving instantly. It is because the spring is starting at 150lbs/in.. so in this case, the force the spring is dealing with is anywhere from 150 lbs to 500 lbs.. you would need to see the spring curve chart to figure out what the actual specs are when the spring is actually compressed at 1". For spring 'B', it's easy to know that the spring is dealing at a force of 500 lbs since it's 1" x 500lbs/in = 500 lbs of compression. The car will have less of a head diving experience. So what does it all mean? In Layman's terms, a progressive spring will have more of a variable spring rate feel because the driving condition and situation keeps changing. For a Linear spring, it's more predictable. Last thing you want when you are driving hard is having uncertainity on how the car is going to act or what to expect. Keefe Keefe Link to comment Share on other sites More sharing options...
Jaxx Posted January 29, 2005 Share Posted January 29, 2005 Progressive springs are wound in and designed in a way that the spring rate compression curve is parabolic, not linear. As the progressive spring gets compressed, the spring rate increases to resist binding or compression, so as the spring goes into compression during travel, the springs are going to have more and more lbs/in until its maximum designed limit. yes but depending on how the coil is wound the progressive (weaker) coils are already bound at full extension -thus working like a helper.. a GC8 front strut is a perfect example Link to comment Share on other sites More sharing options...
CRAZY KEN Posted January 31, 2005 Share Posted January 31, 2005 ...that's right gents...ask The Big Daddy of BOSE wave radio, lifestyle and speakers...Some of you may have heard of his new "Strut/Spring" combo using sound waves...that's right...SOUND WAVES!!! It's being experiment on the NEW Corvette as we speak!!! So in the future...people will forget about progressive spring and say hello to BOSE!!! CRAZY KEN P.S. He has over 30 years in R & D with this type of technology...he was always fascinated with the automobiles suspension. This will overtake/revolutionize the MacPherson Strut!!! Link to comment Share on other sites More sharing options...
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