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Ghost
12-30-2006, 09:37 AM
Over the past year I’ve seen plenty of reviews in the performance section here on the boards about exhausts, intakes, and most of all F/I systems. Many of these detailed threads have more than 15-20 pages of great information. Some of the posts contain misinformation or useless replies, but there are also plenty of quality discussions that greatly help the Z community with their technical knowledge as well as their buying decisions. I have been researching suspension for my Z even before I got it. During my many months of research I have noticed the lack of knowledge and the lack of technical reviews for suspension setups. So I decided to help the Z community out by starting an organized way of submitting suspension reviews. But the main objective of this is to provide detailed technical information that could benefit everyone in their buying decisions, and aid them in the tuning of their own suspension. I was going to start this for coilovers only, but if you would like, please post any other review you have on other suspension parts as well! If you have already posted a review, an updated review would be great to really comprehend the overall performance and reliability over longer periods of time. Also, I have to give props to Z1 Auto, AutoRnD, LosingGripII, and GSedan35 for helping and answering many questions!

VERY IMPORTANT! :
First, EVERYONE should realize that suspension has too many variables to list and not one product may feel the exact same on two different cars. With all the adjustability coilovers have, it is really almost impossible to compare a coilover setup on another car with different suspension mods, LSD, wheels/tires, tire pressure, temperatures, weight reduction, etc. With that being said, this should not be a taken as if it will transform your car the way you want it to behave. BUT, this FAQ can be a VERY useful tool if used as more of a guide to get you in the right direction. This can be a excellent starting point for some, and then make fine tuning easier on your particular car. It could also be a guide for people looking to buy suspension that need technical information from others to find out what will be best for their particular needs.

The reviews should be very detailed and as technical as possible. It is very important to go into detail about the changes in the car’s driving characteristics over stock. This way, it can be easily compared for people who have been riding on stock suspension thus far. If anyone has had the chance to drive on numerous sets of coilovers, then PLEASE go into detail about the different driving impressions that you could observe from their different setups. (I know most people haven’t had this chance, but some people in bigger cities can drive friends cars with other suspension setups, as well as shop owners that have the opportunities to drive customer’s cars.)

Reviews:
Here are some things to consider when writing reviews. Once again, its very important to use this as a starting point, not a dead end result. Remember that other parts of the suspension will make a significant change on the ride and performance of the handling as well.

Adjustability/Features/Ease of use/Quality and Design:

Single/Double height adjustability (spring preload and height adjustable)

Shock Construction (Monotube/Twin Tube)?
Inverted shocks?

Adjustable Damper (Y/N)? If so, how many increments can the dampener be adjusted? How does each increment feel? Can you feel the different between one click, or does it take 2-3 clicks to really feel a difference? (FOR EXAMPLE ONLY: some 30+ way adjustments are used for marketing tools to make you believe there is more adjustability in their shock, but really it could only be felt in 12 different adjustments, so what you thought is a 30 way adjustable damper is really only 12 way.)

How do you adjust the shock? (tool, knob, etc) Are there numbers representing the amount of stiffness that the shock is set on?

Any thoughts or opinions on the quality and design should also go here. The design of certain parts like the pillowball upper mounts, spring/shock perches, threaded length on body, mounting designs, piston diameter, helper springs, materials used, etc…
For example, there was a great review on the 240sx forums a while back when I used to own an S14, comparing Tein He’s to JIC Magic FLT-A2’s…There were detailed pics of every part on the coil over. The pictures showed that some of the parts used on the JIC where beefier, stronger, and of better quality.

Comfort/daily drivability aspects:

How comfortable is the ride on the street?

Obviously you will give up smooth riding for better handling, but as many should know, some shocks that are properly valved to the spring rates, the ride can be smoother while having better handling (being stiffer) than one with a poorly matched shock and spring. Including different circumstances here also helps in understanding the drive quality. Some circumstances should include how the ride behaves over bumps in a straight line at low speeds VS high speeds, or while cornering over bumps or uneven/wavy pavement. Also, discuss any noises or other annoying problems that you might have that could affect daily drivers.

Performance aspects:

This is of course the most important part of the review that has been the most lacking in the past reviews that I have read. Here we want to talk about how the coilovers compare in driving characteristics to the stock suspension. If applicable, compare the coilovers to a past set that you might have had, or to a set on a friends/customer’s car that you may have had the opportunity to drive. In this part of the review its very important to thoroughly discuss the characteristics of the car, by this I mean discussing the behavior of the car: the way the car turns in, accelerates through corners, stability in corners/and at high speeds, weight transfer, response, the limits of the suspension over stock, and most importantly over steer/under steer. Another thing you could list here is your other suspension mods that might have an effect on the feel of the car along with the coilovers. Things such as different wheels/tires, alignment, sways, etc will greatly effect the behavior of the car. By listing them you can give other readers a better understanding of what is effecting the cars handling.

*Technical Info You NEED To Know About Suspension:*
***Credit and Appreciation to Whiteline for their excellent products and great info in these articles***
(Don’t for get to go down to the bottom and push next page for the rest of the articles…most of them have several pages!)


Shocks FAQ (http://www.whiteline.com.au/faqshocks01.htm)
Springs FAQ (http://www.whiteline.com.au/faqsprings.htm)
Sway Bars FAQ (http://www.whiteline.com.au/faqswaybars.htm)
Wheel Alignment FAQ (http://www.whiteline.com.au/faqsusp01.htm)
Wheels and Tires FAQ (http://www.whiteline.com.au/faqtyres01.htm)
Excellent Coilover Article! (6 pages) (http://www.whiteline.com.au/articles/coilover_H4s_2000a.htm)
General Info on Suspension (http://www.whiteline.com.au/articles/Hot4s_88_Susp_1.htm)
Good Article on Suspension Vs. Cost (http://www.whiteline.com.au/articles/skidmarks2a.htm)
Tuning and Diagnosing Suspension Setups
(http://www.whiteline.com.au/articles/skidmarks3a.htm) Nismo S-Tune Suspension Review (http://www.my350z.com/forum/showthread.php?s=&threadid=23484&highlight=coilovers)
Tein Flex Review (http://www.my350z.com/forum/showthread.php?s=&threadid=36540&highlight=coilover+review)
KW Variant 3 Review (http://www.my350z.com/forum/showthread.php?s=&threadid=52683&highlight=coilover+review)
Nismo S-tune Review (and sways) (http://www.my350z.com/forum/showthread.php?s=&threadid=35043&highlight=coilover+review)
HKS Hipermax II Review (http://www.my350z.com/forum/showthread.php?s=&threadid=23537&highlight=coilover+review)
HKS Hipermax II Review (http://www.my350z.com/forum/showthread.php?s=&threadid=77624&highlight=HKS+Hipermax)
HKS Hipermax II Review (http://www.my350z.com/forum/showthread.php?s=&threadid=112566)
Cusco Zero 2 Review (http://my350z.com/forum/showthread.php?s=&threadid=28328&highlight=cusco+and+coilover)

All this info is the basic information you need to know about suspension. This pretty much covers all the general suspension information that I can find for the moment. I was going to initially take the time and write out this stuff, but I remembered Whiteline’s FAQ on their site from when I bought their sub frame bushings for my S14. Another huge thanks to Whiteline!

Since most of the general suspension knowledge should be comprehended from the above articles, it would be great to focus this thread mostly on suspension topics pertaining to the Z/G community. Whether its certain setups/settings, driving impressions and reviews on suspension products, or tuning and diagnosing the Z/G’s suspension and its characteristics.

Mike

Ghost
12-30-2006, 09:38 AM
The following is a compiled list with minor corrections from GSedan35
He did a great job on getting together the list of spring rates and other information on this list.

OEM springs
Front:314 Rear:342

Tein Flex (twin tube construction, adjustable dampeners
Full-length adjustment and height adjustment for separate setting of the height and spring preload
672/672 F+114% R+98
Transfers +16% roll stiffness to front
Damper Adjustability: 16-way Adjustability
Side Note: Extremely high spring rates mean even when the adjustable damping is set as low as possible, you may not find ride quality happiness, several reports of this setups harshness exist Yet a few owner comment’s of a “like stock ride quality” also exist. However given the fact that they use a spring stiffness that’s over 100% stiffer then oem, if ride quality is of concern, either hitch a ride in a car equipped with them or make a different choice. In addition, several review’s have been done by people actually having the original more softly sprung Tein Flex coilovers do not take their comments to mean the same as the one using the current product, the original product specs are listed below under Tein Flex JDM.

Tein Flex JDM specs (can be special ordered est 6-8 weeks delivery)
Full-length adjustment and height adjustment for separate setting of the height and spring preload
560/560 F+78% R+64%
Transfers 14% roll stiffness to front
Damper Adjustability: 16-way Adjustable
Side Note: This is the original specs first offered in the U.S. with the Flex, shortly after it’s introduction the specs changed to those listed further above (672/672)


Tein Basic (twin tube construction, non adjustable dampeners )
504/504 F+61% R+43%
Transfers +18% roll stiffness to front
Side Note: Excellent value at it’s price point, some very good reviews have been done by users of this coilover system.

Tein SS (twin tube construction, adjustable dampeners )
(JDM only at this time. 6-8 weeks delivery, come via ship)
392/314-392 (rear’s are progressive)
F+25% R+15% at peak


Tein CS (Monotube construction, adjustable dampeners )
Side Note: A comfort ride system compare to HKS LS
392/392 F+25% R15%
Transfers +10% roll stiffness to front
Special Note: I had a conversation with Tein about this coilover. I called because I had a hunch that the comfort tuning designed into the system would prevent me from getting the dampening stiffness I wanted. When I told him I wanted a system that would be valved stiffer then oem 350Z shocks, he did not believe they were setup to do that. Revalving them would be $300 or so PER! dampener.


Buddy Club Racing Spec coilovers (Monotube construction, adjustable dampening)
Full-length adjustment and height adjustment for separate setting of the height and spring preload
748/280*
(very likely run's rear springs on the dampener body and not at the oem rear spring location)

Jic Flta-2 350Z fitment (Monotube construction, adjustable dampening)
Full-length adjustment and height adjustment for separate setting of the height and spring preload
Piston Size: 40mm
Damper Adjustability: 15-way adjustable
Special Note: This setup is known for it’s street ride harshness, but also for track performance
560/672 F+78% R+98%
Transfers +20% roll stiffness to rear

Jic Flta-2 G35 coupe (Monotube, adjustable dampening)
Full-length adjustment and height adjustment for separate setting of the height and spring preload
560/560 F+78% R+64% $1750
Transfers 14% roll stiffness to front

Jic Flta-2 G35 sedan (Monotube, adjustable dampening)
Full-length adjustment and height adjustment for separate setting of the height and spring preload
504/392 F+61% R+15%
Transfers +46% roll stiffness to front

Cusco Zero 1&2 (Monotube, 1=non adjustable dampener, 2=adjustable dampener)
Full-length adjustment and height adjustment for separate setting of the height and spring preload
560/392 F+78% R+15%
Damper adjustability: (for Zero2’s only) 5-way adjustable
Transfers +63% roll stiffness to front (no they do not run their rear springs on the dampener body, oem location, seen them on the car with my own eyes.)
Side Note: That’s a awful lot of spring stiffness to move to the front

Bilstein PSS coil over (Monotube construction, non adjustable dampeners)
Special Note: Mild spring rates, but Bilstein says the dampeners are performance valved
370/240-420 (rear progressive) F +18% R +23% (at peak rear spring rate)
Transfers +5% roll stiffness to rear
Piston Size: 46mm
Special Note: Very easy to ditch the rear progressive springs that come with the Bilsteins (I would) Eibach sell's linear 5" O.D. springs that you can swap in, $100 for the pair.

Bilstein PSS9 coilover (Monotube construction, adjustable dampeners)
Special Note: Mild spring rates, but Bilstein says the dampeners are performance valved
370/240-420 (rear progressive) F +18% R +23% (at peak rear spring rate)
Transfers +5% roll stiffness to rear
Piston Size: 46mm
Damper adjustability: 9-way adjustable
Special Note: Very easy to ditch the rear progressive springs that come with the Bilsteins (I would) Eibach sells linear 5" O.D. springs that you can swap in, $100 for the pair.


ATTENTION! HKS will be opening a U.S. service center very shortly, allowing for service and repair on their coilovers here, without sending them to Japan.

HKS LS+ G35 Coupe (Monotube construction, adjustable dampeners)
504/448 +58%front +29% (rear springs are progressive)
transfers 29% roll stiffness to the front
Side Note: Tuned more aggressively then the LS.
Special Note: This G35 coupe version, while transferring roll stiffness to the front vs the same 350Z version, does actually use stiffer valving in it's dampeners then the Z version.

HKS LS+ 350Z (Monotube construction, adjustable dampeners)
448/448 43%front +31%
transfers 12% roll stiffness to the front
Side Note: Tuned more aggressively then the LS, but not to the RS level, in spite of the RS actually using softer spring rates. Special Note: This 350Z version does not transfer as much roll stiffness to the front as the G35 version, but does use softer valving specs in it's dampeners.

HKS LS G35 (Monotube construction, non adjustable dampeners)
448/336 F +43% R -1%
transfers 44% roll stiffness to the front
Special Note: A comfort ride system, compare to Tein CS coilover

HKS LS 350z (Monotube construction, non adjustable dampeners)
448/448 F43% R+31%
transfers 12% roll stiffness to the front
Special Note: A comfort ride system, spring rates make better sense then same G35 application, compare to Tein CS

HKS HIPERMAX II (Monotube construction, adjustable dampeners)
504/504 F+61% R+47%
transfers 14% roll stiffness to the front
Damper Adjustability: 30-way Adjustable
Special Note: sprung and valved to be HKS’s most aggressive product, it is a notch above the RS coil over on the track, compare to Tein Flex and Jic coilovers

HKS RS (Monotube construction, adjustable dampening)
448/448 F+43% R+31%
Transfers 12% roll stiffness to the front
Damper Adjustability: 30-way Adjustable
Special Note: “Marketed” as HKS’s track coil over with a good street ride, it is more aggressive then the HKS LS+ and does not transfer as much spring stiffness to the front.

Zeal function V6 coilover (Inverted Monotube construction, adjustable dampener) $2855
Full-length adjustment and height adjustment for separate setting of the height and spring preload
560/448 F+78% R+31%
Transfers +47% roll stiffness to front
Damper Adjustability: 6-way Adjustable

Tanabe Sustec Pro S-OC
Twin tube damper
Helper Spring: Yes

Tanabe Sustec Pro S-OC II
Twin Tube damper
Helper Spring: No

Tanabe Sustec Pro S-S
Twin Tube damper
Helper Spring: Yes
Damper Adjustability: 4-way front/ 8-way Rear Adjustable

Tanabe Sustec Pro S-S II
Twin Tube damper
Helper Spring: No
Damper Adjustability: 4-way front/ 8-way Rear Adjustable

KW coilovers Variant's 1,2&3
Monotube construction, V1=non adjustable dampening, V2=adjustable damping, V3=separate adjustability for compression damping AND rebound damping and is the only product of it’s kind at this time.
Front: 485lbs to 525Lbs Rear: 240Lbs to 548Lbs (progressive springs)


D2 Racing Coilovers (Monotube)
840/728 F+168% R+113% (wee bit stiff eh, the recommended rate to)
Transfers 55% roll stiffness to front
Side Note: Only known application of this coilover was by a vendor wishing to sell it, upon installation it was determined that the ride quality was so poor that they were pulled from the car and any idea of carrying the product was shelved.



Kg/mm DNA coilovers (Monotube construction, adjustable dampeners)
840/280*+
JDM only at this time, $2700+
These look like they are made by buddy club.
*They use rear springs on the rear coil over bodies AND a progressive spring in the oem location. The best I can get translating is that the progressive spring adds 200lbs to the rear rate.

Other coil over available:
Esprit
Quantum
Aragosta
Kei Office
Veilside
Ohlins
Blitz
PROs engineering
Mines
GAB
Racing Gear


MORE TO COME!!!