albertgoq

Hi

Just researching on springs and spring rates? OE spring rates on our 2IS is, I find the f-sport on both f-sport shocks or even OEM tokico rather harsh especially on poor/average roads. they are great on good roads and highways. I am not much into the performance end of the springs, like cornering, running 60mph on sweeping curves and having no roll. Just want to get rid of the fender gap and have a nice comfortable ride. by achieving just a 1' drop all around. So my question is if swift and tanabe has the nearest spring rates to OEM, that would yield the most comfortable/OEM like ride, while having to use the stock shocks?

OE Rate
5.4kg/mm front
5.6kg/mm rear

Swift Springs
4.6kg/mm front
5.2kg/mm rear

Tanabe NF
4.9kg/mm front
5.8kg/mm rear

RS-R Downs
4.48kg/mm front
6.0kg/mm rear

Tein H-Tech
6.0kg/mm front
6.3kg/mm rear

F-Sport by Eibach
4.7kg/mm initial rate front
4.0kg/mm initial rate rear

6.6kg/mm final rate front
7.0kg/mm final rate rear

all these springs claim a 1" drop front and .5'' to .8" drop rear which is ok to my preference

FSportIS

iTrader: (13)

If you want to maximize comfort while lowering the car a bit. I advice you either go with Swift linear spring rate or F Sport springs and pair them with stock shocks. Don't go any other shock because they are stiffer.

The F Sport springs (made by Eibach with Lexus specification) feel soft to me, it rides like stock while the Eibach IS250 version feels stiffer.

JETLEX

iTrader: (11)

I'll disagree with getting the stock or F-sport shocks if you want a slightly softer ride - look at the Tokico HTS adjustable shocks.

I was looking for the exact same thing - slightly more compliant ride, while keeping as much handling performance as possible. I spoke to one of the engineers at Tokico, and he told me the HTS can go apx 1-3% softer than stock (at least in the rear). It sounds like a small amount, but it made all the difference to me.

I also installed Swift Sport lowering springs after that, and I would say that it helped just a tiny bit with 'compliance', while handling is actually slightly better (rotation, etc).

I had the F-sport setup before, and wouldn't recommend it in comparison.

HTH

FSportIS

iTrader: (13)

The Lexus stock shocks are made by Tokico with Lexus specification and Lexus always prioritize comfort over performance on a stock car.

Also, I did NOT recommend F Sport shock for comfort in my previous post, i said "stock" shock.

Gville350

iTrader: (10)

The problem is that the springs are not matched to the valving of the shocks; so matching mix-matched brands isn't optimal. Either opt in for http://www.ebay.com/itm/BC-RACING-FULL-COILOVERS-06-10-LEXUS-IS250-IS350-IS-F-ISF-GSE20-KIT-/231215384986?pt=Motors_Car_Truck_Parts_Accessories&fits=Make%3ALexus%7CModel%3AIS250&hash=item35d582c99a&vxp=mtr or go with a proven set of http://www.ebay.com/itm/KONI-1140-Sport-Lowering-Kit-06-13-Lexus-IS250-IS350-RWD-excl-IS-F-AWD-/321402067130?pt=Motors_Car_Truck_Parts_Accessories&hash=item4ad50e58ba&vxp=mtr.

albertgoq

but what if I get swift springs? the drop is not that great but it should reduce the fender gap and here are the spring rates .8 to 1' drop front and .6" rear

OE Rate
4.5kg/mm front
5.2kg/mm rear

Swift Springs
4.6kg/mm front
5.2kg/mm rear

almost near as stock?

Noeh

iTrader: (3)

swift springs will ride as stock

albertgoq

if the swift springs are paired with the bilstein F-sport shocks how would it feel would it stiffen up the ride?

BTW what are the F-Sport Bilstein Shocks are they the Bilstein C, HD, or Sport?

FSportIS

iTrader: (13)

If you want comfort, go with Swift springs with stock shocks. F-Sport Bilstein shocks are made to pair with other stiffer springs and will make the rides stiffer regardless what springs you use. I believe F Sport shocks are Bilstein sport shocks with Lexus specifications.

azfsprt

iTrader: (4)

Yes they are but they are not adjustable unfortunately but bilsteins are the next best thing to Ohlins. ;-)

Gville350 hit it right on the head If you truly want the setup closest to comfort then you really should get coilovers as they are optimized together.

Your next best option is to get adjustable shocks like Koni sport yellows (They make one of the best adjustable shocks) or the Tokico hts... Based on my experience on previous cars on lowering springs you need adjustable shocks to suit the height and tension differences of the springs to adjust for the different rates and tensions to suit your comfort need.

Take a read here, I used this as reference when I was looking for springs on my other cars before.
http://www.hrsprings.com/technical/

reyoasian

iTrader: (2)

F-Sport shocks and springs are optimized to be together too

If OP got RWD, I'd say go for some decent coilovers such as KW (the V2 is more than sufficient for street use)

If you really want to opt for springs, Swift would be my first choice and H. Techs second (from your list). They have minimal drop but are linear. I would never buy another set of progressive springs, ever again.

I've driven:
2006 IS350 with S. Techs on stock shocks
2008 IS250 with Eibach Pro on stock shocks
2009 IS250 AWD with H&R sport on stock shocks
2009 IS250 AWD with RM on F-Sport shocks
2008 IS350 on BCR coilovers with standard springs rates and max stiff on shocks.
Out of these 4 setups, the second last one is actually the most comfortable. The last one killed my back.

albertgoq

eibach rates

these rates are not bad for progressive springs

Pro Kit IS250
Spring rates
front 3.5kg/mm initial rate to 5.6kg/mm final rate
rear 3.8kg/mm initial rate to 6.3kg/mm final rate
Lowering front 1.4" rear 1.0"

Pro Kit IS350
Spring rates
front 4.0kg/mm initial rate to 5.6kg/mm final rate
rear 3.8kg/mm initial rate to 6.3kg/mm final rate
Lowering front 1.0" rear .8"

Eibach branded springs has the softer rates as compared to F-Sport Springs that are made by Eibach

F-Sports are a lot stiffer and as you install the springs when the weight of your car sits on the springs the rates already increase

F-Sport by Eibach
4.7kg/mm initial rate front
4.0kg/mm initial rate rear

6.6kg/mm final rate front
7.0kg/mm final rate rear

albertgoq

thanks for the input maybe swift on stock shocks or F-sport shocks, what do you think

else I have to post the F-Sport Shocks and Springs in the For Sale Section

A_Grasso

iTrader: (13)

Lol Reyo you would hate life in my car... 16k/12k bcr's haha. But to the op: my friend used to have the tanabe DF 210? A while ago and they were very comfortable. I've heard swift are also very comfortable, as well as h.techs. I'd say just sell the fsport shocks and springs and buy a set of new coilovers. If you do coilovers just get Megan EZ street for sub 700 bucks and call it a day. You'll be able to lower and raise your car yourself whenever you want and also choose how soft or stiff the ride is. Hope this was helpful

pmanliu

iTrader: (4)

How can you tell if a set of springs are progressive? Mainly trying to see if the S-Techs are