I emailed Tanabe about their springs being progressive or linear, and this is their response:

Here is some suspension 101

The GF210 coil spring is geared more towards performance and track use due to its more linear rates and higher spring rate, but is completely suitable for daily driving.



Regarding progressive and linear rates, there is a lot of misinformation on the internet as to what is better, why, and what to look for. Many people tend to ask "Are they progressive or linear?" For standard coil springs that mount to OEM style shocks and struts, they cannot be one or the other.



Standard automotive coil springs (with the exception of fixed diameter springs for adjustable coilover suspension) are both linear and progressive. For drivability and ride comfort, a portion of the spring uses a progressive rate, while the majority is linear. One thing that sets different manufacturer's springs apart is the percentage of progressive 'coils' on the spring versus the linear 'coils'



The GF210 for the Lancer EVO VIII is predominantly linear.



Typically the progressive coils are wound tightly together and are located on the the top and bottom of the spring. The center portion has evenly spaced coils, which is the linear rate.



What dictates how many progressive coils a spring should have? This can only be determined through thorough R&D, and is dependent on many factors, including upper and lower OEM spring perch, weight of the vehicle as well as several others.



The progressive coils located on the top and bottom of the spring help with daily driveability and work to absorb some of the shock from irregular road conditions.



A common misconception is that the struts dictate driving performance. Struts, also called dampeners, work in conjunction with the spring to ensure that the bound and rebound of the suspension is not too quick, or too slow. The majority of suspension travel and handling is performed by the coil spring. If a shock (or adjustable coilover in many cases) is valved too stiffly, it is not allowing the spring to perform it's function. This is a huge misconception with many people who are looking for adjustable coilovers and look strictly at the dampening stiffness as a gauge of 'performance.' A stiff dampener does not compress nor rebound quickly, which means the contact patch of the tire with the ground is not optimal or at 0%. A proper spring/strut combo or adjustable coilover suspension will have a spring rate and internal valving that is mated to complement each other. "Stiffer is not always better"



Tires are the only thing connecting the car to the road, if the contact patch is not optimal or non existent, then handling performance is degraded.







Best Regards,
Tanabe Racing Development, USA

 

that was a pretty nice write up that guy sent you. it was very informative. thanks for posting it man.

 

White - thanks for posting the reply. I interpret it to primarily mean "trust us, we know what is best" : )

The rears look like there is a low spring rate section (coils close together) and a longer high rate section. The fronts looked pretty well linear to me. So what they are saying makes sense about the evo springs being predominantly linear.

 

Here is some more correspondence from Tanabe including my email they were responding to:

Hello Tim

Each spring is researched and developed at our ISO 9001 certified Shiga Manufacturing Facility in Japan. All Tanabe coil springs have a tensile strength of 2100 nm (highest in the industry) and all are pre-loaded to 100% during production and quality control so that they will never sag. There is a very thorough article on our manufacturing process in this Month’s Import Tuner.

For raw data on handling, lateral g’s, skidpad, etc that information is held by our engineers in Japan and we do not currently have access to it.

Best Regards,

Tanabe Racing Development, USA



-----Original Message-----

To: info@tanabe-usa.com
Subject: RE: Important question on GF210

Thank you very much for response. This helps clear up many issues.

My remaining question is, Does Tanabe test each spring out on every car or is the GF210 a generic spring for multiple cars? You say R&D goes into the development. As an engineer, I would love to hear some of the performance increases you saw in the Mitsubishi Evolution 8 development.

Thanks

Tim

 

So what is the verdict on the steering turn in? Is it the same as stock or do you lose the response?

 

I have the GF210 springs on my Evo. The initial steering input seems to be close to stock. Although I believe it maybe a little slower on initial turn in. It is such a slight change that it is barely noticeable to me. I have to concentrate very hard to feel the slightly slower initial turn in. The springs ride real good IMO. Everyone likes the way it looks now. It looks less like a grocery getter and more like a sports sedan. The hood seems like it is much lower, but the front lowered only about 40mm . I highly recommend the springs, especially for the price that revhighonline was selling them for. You mush get an alignment after the springs, for sure. The camber changes alot but the alignment can get you back into spec, no problem. The guy at the Mitsu dealer who aligned my car, has an evo with the Tein S on his. He had to get a camber kit on the rear to get his back in spec. He liked the way my car looked and wished he had gotten the Tanabes because his was such a PITA to align.

Brian

 

I received the shocks today. I will say that the rears seem a little more progressive than I would have liked. I posted a picture in the spring rate chart thread. I will install them next week and give my opinions.

 

good review, liked mine when i had em too!

 

old thread but good review Im really considering these springs haven't heard many negatives on them

 

I love my gf210 springs. The stance is perfect, not overly aggressive. Rides really well, not too stiff or soft. Just got an alignment, no issues whatsoever. Best springs for the price!

 

holy old thread bump batman..

i like the tanabes. bought them used off of here and they are great. not too low, but with my 255/45/17's it fills the wells pretty well with minimal rubbing on the inner fenders (tire size on stock evo8 rims).

 

Just moved on from these springs cause they were a bit to low for the roads here in NY. They are definitely the best of both worlds when it comes to looks and performance, not to mention price too. If anyone wants a set with less than 5k on them let me know.

 

anyone know tanabes spring rates?

 

Click the link in post #67!!

 

If anyone is looking for a set with only 2K miles on them just PM me.