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KW Springs vs Swift Springs

I have tried both sets of springs now and can say that the current setup works best for me I run the 12K front and 8K rear with 60mm helper springs @1.5K and 3K.
I think that is 657/457 and all 60mm
 
I bought 10k/8k swift springs last year and made the mistake of buying the 170mm front spring. This is not correct - you'll need the 152mm front and 203 mm rear. ID is 60mm.

What makes the "170mm" length wrong? I bought the 7" (178mm) Swift 8k springs for the front using the stock KW helpers and it works great for me. I considered getting the 6" (152mm) springs. I'm just curious behind the reasoning.
 
What makes the "170mm" length wrong? I bought the 7" (178mm) Swift 8k springs for the front using the stock KW helpers and it works great for me. I considered getting the 6" (152mm) springs. I'm just curious behind the reasoning.

The 7" spring didn't work for me because the ride height was too high unless you drop the spring perch all the way (not ideal). I contacted Daniel at iliftsystems after installing the 7" spring and he recommended the 6" which worked out perfect for me.
 
The 7" spring didn't work for me because the ride height was too high unless you drop the spring perch all the way (not ideal). I contacted Daniel at iliftsystems after installing the 7" spring and he recommended the 6" which worked out perfect for me.

I gotcha. Do you have an iLift system, or just his top hats? I have the iLift top hats on my KW.

I guess I'm not at an "ideal" height, but so far it's working for me. I definitely had some room below the bottom perch at my current ride height though. I appreciate the answer back!
 
I gotcha. Do you have an iLift system, or just his top hats? I have the iLift top hats on my KW.

I guess I'm not at an "ideal" height, but so far it's working for me. I definitely had some room below the bottom perch at my current ride height though. I appreciate the answer back!

No currently using oem top hats, one day I'd like to switch the ilift versions. :smile:
 
If you install the iLift system you'll want front spring lengths of 140.

No currently using oem top hats, one day I'd like to switch the ilift versions. :smile:
 
Gents, forgive my relative ignorance (and the "necro" bump), but would I be correct in assuming that most all coilover options would require 60mm ID springs, with a front length of 152mm and a rear length of 203mm?

(Asking because I'm in the market for new springs for my JRZ RS's. NOTE: The RS's have helper springs)
 
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For the record, spring rate balancing IS a real thing. Many race teams rates their springs and pair them on their own, engraving the true rate onto the spring itself. Swift and Hyperco are some of the most popular in north american professional racing due to their consistency. Eibachs vary A TON. This is really important when a 25lb rate change can make a difference in the car's handling and balance. Many Eibach springs are well over 50lbs off.

A few things:

I have tried both swift and the KW's and even swapped between them at the track for back to back testing. (covered somewhere here on prime) With my car and set up I was constantly faster and preferred the higher rates of my Swift set up. 12/10kg if i remember correctly. The rates you want to go with depend on the Hz required to dampen the unsprung mass. Then take into account the tire compound that you plan on running. My numbers were based on OEM calipers, my Regamaster Evo wheels and Nt01 R-comps. My apples may be your oranges.

You don't want to overspring the KW's. Again, memory is telling me the valving can only handle 10kg above what they ship with. I stayed within that and still blew a shock. Warranty was a bitch but they eventually handled it even though I had to pay for shipping both ways.

Yes, spring manufacturing and manufactures make a difference. Its not all marketing. I personally know of a specific instance where a big name race shock company switch from one brand of spring to another after the first was caused them to start a re engineer process of the shock itself.. until they found out what the real problem was. For 90% of people its not an issue. But to Regans point the people that have high dollar set ups, are chasing 10th's, or just care to look deeper all of that stuff indeed matters.
12/10 is what Fightex Dampers used, and is a similar balance as RYU's DG5 (if he swapped his spring rates), and a similar balance to CL65 Captain, what FXMD ran in the 2008 Super Lap Battle, what KW initially recommended on the FXMD NSX for their Triple Adjustable race dampers, and a not far off of what Jim ran on his K-Sports or what Factor-X (FXMD) ran, and the common setup of 1,000/800. So it's a pretty common balance for the NSX.

I have tried both sets of springs now and can say that the current setup works best for me I run the 12K front and 8K rear with 60mm helper springs @1.5K and 3K.
I think that is 657/457 and all 60mm
Your spring rates result in stiffer front wheel rates than rear. Jeff Shoots ran this setup on his 2-way Motons with a 1 1/8" front bar. Pretty stiff front end....
 
I like a stiff front end... this probably wont end well

you are correct its stiff but planted through the corners, I must admit I feel like I've done a work out at some tracks now but the car is stable
 
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