Cutting stock springs is NOT recommended.

 

would you guy say that u need after market camber/toes stuff if u get the TANABE SUSTEC DF210 and the D-spec shock? (since the drop is pretty low). could someone also translate FR: 6.3kg/mm RR: 7.0kg/mm into lb/in please.

 

^ yes, you'll need to get camber kits with that setup.

 

Here you go:

Re: spring rate conversion
by Robert Fogt on 03/16/05 at 1209


Springs are rated in pounds/inch in the U.S., and Newtons/millimeter elsewhere. I have not seen kilograms/millimeter before, but the conversion will be easy enough.

1 pound = 0.45359237 kilogram
1 inch = 25.4 millimeter
0.45359237/25.4 = 0.0178579673228346

The conversion factor is 0.0178579673228346

So, to convert lb/in to kg/mm you multiply by 0.0179 and to convert kg/mm to lb/in you divide by 0.0179

 

Thanks!

 

Anytime.......when I am awake of course

 

ok now can someone comment on that fact that the tanabe DF's are progressive, i heard thats not really great. and whats Spring rates in LBS 308/353 mean? or will its not matter if paired with the d-specs?

 

Progressive???? Hmmmm looking at the picture...it might be. The coils at the top appear to be tighter wound versus the middle section. However at the same time...it might not be a performance spring in regards to handling. This looks to be a compromise between comfort and better handling (by lowering the center of gravity more than increasing the stiffness). The NF210version of the springs look to be more linear in the overall coil space and the spring rates are indeed stiffer.

The spring rates I am sure have a more technical explanation versus the one that I am going to say but I am not that hard core so here goes. Just go with the rate comparrison of higher numbers = stiffer ride potentially better handing response. Lower numbers = more comfort not as crisp handling, but potentially still better than stock handling due to lower center of gravity and the springs just have to be slightly stiffer than stock to hold the same amount of weight on a "shorter" spring.

Use the numbers as a guage in how the ride is going to be. Read on the reviews of the Tein S-Tech and
H-Tech...look at the spring rates on those and then compare them to the Tanabe's. From there you should be able to interpolate the data and draw somewhat correct conclusions on the handling and comfort characteristics of the chossen application.

 

^ nicely said, however its hard to access the spring rate when the springs are progressive. i still don't know what LBS means. is that the spring rate when...not being compressed (like during turns)... or what?

 

im thinking of getting Tein H tech on stock stuts what do you guys think?

 

thats lbs. as in pounds

 

As mentioned the measurement on the lbs/in versus the kg/mm...I am not too sure where and/or when they are measuring that specific number. I would think that that rating is how much force is needed to compress the spring per inch or per mm. I would guess that it takes the "X" lbs or kg to compress the spring 1 in or mm in regards to distance traveled.

If what I assume is correct then the higher rates equates to a stiffer spring due to the added amount of force needed to move the spring "X" amount of distance.


Found these postings though:

Tein H-tech 350z linear springs .3”/.2” drop on 350Z G35 drop will be higher
Spring rates in LBS 358/375
Stiffer then oem springs by F+14% R+11% (see note at very top)
Transfers +3% roll stiffness to front

Tein H-tech G35 coupe & sedan(fronts are progressive, rears are linear)
Spring rates in lbs 324/260 (final rates only, softer intial front progressive rate unknown)
Stiffer or softer then oem springs by F+ 5% R-22% (see note at very top)
Transfers +27% roll stiffness to front


There is a compete discussion on these things here:

https://g35driver.com/forums/brakes-suspension/65190-g35-350z-aftermarket-coilover-springs-shocks-spec-s-w-updates.html

They go over all the data and rates. Be advised though...that even though you get a stiffer spring...that does not automatically equate to better performance. The spring rate AND shocks need to be matched. Remember you are still going to be on stock shocks. In time, you may blow out the shocks as well. They were not made to be matched with stiffer springs on a shortened length, this decrease in height is what causes an increase in pressure in your stock shocks and later leads to the shock failing.

Anyhow...once again goodluck with the projects. Its a learning experience...some fail (expensive as crap leasson) and some go well. Roll with it. As long as you understand that you really do have to "pay to play" and that opinions on these boards should never be taken as absolute gospel and the end all to all questions. Keep digging and do your own homework as well. It will make the decision more comfortable and reasuring to you.