occxlr8ed

Just got my 2010 IF and after some coilovers 100% for street use, and for lowering. I've had them in the past with my evo X but didn't play with spring rates.

I've read around and the most popular is 14k/10k? Here in Australia we can't get the swift spring upgrade so I'll be sticking to the stock BC springs.

OR

I can go Tein Comfort Sports?

Opinions?

Cheers!

bnizzle87

Tein Comfort Sport Techs are 12k/10k. I had them before and they were great for cruising and not really pushing the car. The BC Racing 14k/10k is slightly better and I've heard good things with those spring rates. It's a shame you can't get the Swift springs upgrade, because many members here have positive feedback from them. Both the BCs and Teins are a good option, but it depends on how much you're willing to spend and which company can rebuild them for you the closest in the event there's a leak from any of the corners.

occxlr8ed

I've in the past replaced the pillow tops in my old BCs without any issue so that's easy!

I guess not knowing much about spring rates at all I just don't want to detriment the ride quality of what is a sports luxury car! Was wondering how the 14k/10k springs are vs the stock setup on the 2010 isf!

bnizzle87

I've driven a 2010 IS F before and then took a ride in my friend's 2010 with BC Racing coilovers (non Swift springs upgrade), and the difference was slight. It handled better, had less road feedback/less jarring on road imperfections, and took sharp turns pretty well. I'd say Tein CST lends itself to a more luxury ride, while BC's rates are more for the sporty ride. I had no complaints with the Teins, especially since I was constantly riding with parents and elderly people. If they didn't complain, you knew they were doing the job in that aspect.

occxlr8ed

Would you recommend a 12k/10k spring rate then over a 14k/14k combo?

I'm honestly not that fussed about improving the performance that much. I'm not touching the track! Just wasn't keen on lowering springs then ruining the oem struts.

bnizzle87

If it's for street use solely and you're not looking for hard cornering or pushing the car, the 12k/10k would suffice. It's not too luxury because there is still feedback, but enough to where the bumps from the roads are minimized. I know a good amount of owners who are just fine with 12/10. Yes, it's an IS F, but not everyone pushes it hard. You don't even have to lower the car much. It will ride much better with coilovers- less of a hassle by not lowering too much.

occxlr8ed

I may go 12k/10k then....!
Will do a bit more research/more opinions.
Also just ordered the Figs Lowering kit to pair with

vmatheboss

iTrader: (1)

I'm on my way to ordering a set of bc coils with swift spring upgrade myself. I've done research and I was actually worried that 14/10 combo was too soft compared to my 08 stock setup since I have passengers in my car a lot, especially the rear. I'm sure there is a difference in ride quality when it comes to a 2010 F and a 2008 F (I have 08), so my car is a bit stiff and bumpy. I was told a 16/12 swift spring upgrade would be comparable to my stock if not a little better. I use mine for daily driving and don't want it worst than stock.

occxlr8ed

Apparently 2008 till 2010 are the same suspension wise? Only 2011+ have upgraded suspension.

Yeah I just want a better ride than stock without compromising performance adherently...

LionelHutz

I have a thread running about my experience with 16/12 spring rates. In my opinion, they are better than even the OEM 2011 suspension, except on big road imperfections like potholes where they are a little harsher. I would think that 12/10 are far too soft for the IS-F.

Also, how is it that you can get FIGS lowering kit but can't get the Swift spring upgrade through FIGS?

I8ABMR

what are the stock spring rates ?

NYC ES3

iTrader: (7)

Good luck with tht. Lexus knew what they were doing with this car's ride. From what I've read from credible sources. the stock ride is hard to beat if you do not want to sacrifice any performance from the F

FIGS

iTrader: (11)

As I have stated many times and tell many people calling in,springs do not determine ride quality, damping does. Springs set your travel limits and have to do with vehicle weight, braking and acceleration power and traction(tire section width and compound). Damping is how fast you get to your travel limit. The more energy you can put into the suspension, the higher the rates need to be. The less travel you have, the higher the rates need to be to prevent bottoming. Most of the horrible ride in earlier models comes from the poor damping curve which has a steep curve in the high speed fluid range and a very lax slope in the low speed. The result is a jarring ride on small road bumps and a sluggish steering feel and lots of roll when pushed. 14/10 is the lowest rate I suggest just because of the front weight of the car. You will still have plenty of ability to dial in comfort with damping settings. Our intent on spring rate spec is to spare the shock from being overdamped and stressing the seals and valve stacks. This makes them last much longer as well and the settle speed improves by allowing the spring to do more work that the fluid restriction.

Also, if you want the swift springs we can ship you the correct spec to Australia. The cost difference between a prebuilt setup and adding later is only $100 when it comes to the Swift springs vs the standard BC springs. Properly spec'ed shocks are the first step in taming the car and making it much more enjoyable to drive.

Mike

Gymkata

Just ordered BC coilovers w/Swift springs from Figs yesterday. I can't wait to install them. I ordered them in 16k/12k. I also ordered the Front Lower Arm Rear Mount #2 Polyurethane Bushings while I was at it. I was going to get wider wheels and tires, but decided to wait until I need new tires...as my 245/275 Michelin PSS tires have lots of tread left.

vmatheboss

iTrader: (1)

i got 16/12 and its perfect for daily driving...and hanging turns!!