lockedlex

Just installed this on my 2014 IS350C (which has had the full F-Sport treatment for suspension, Sway Bar, IS-F Steering ECU, etc on it for almost 1.5 years). Lots have already been said about this modification, but here's my .02:

PRO:

• It seems to actually stiffen up the ENTIRE front end, basically at the subframe, thereby allowing more road NVH to enter the front side of the car. This then allows the front end of the car to have greater "road feel" transmitting some of that to the steering wheel.
• It doesn't make it generally uneasy/squirrelly or fatiguing to drive (esp. if you're used to cars like BMWs). Still retains some Lexus quality, but not full Lexus isolation.
• Surprisingly, the front end braking is so much nicer. Pretty much dialed out any noise dive.
• I can definitely feel cracks, tar strips, reflectors, uneven/rough road A LOT more now. BUT because it's transmitting this through the entire front end, it seems like I can feel it through the pedals and floor board too, just by a few degrees more than before. NOT enough to feel intrusive, but just a bit more connected to the road and what's happening. This was a surprise, as I expected to feel the road only through the steering wheel, but I like it. It feels much more communicative.
• Installation was 1 hour on the right, 30 minutes on the left (once I knew what tools and best methods were. I did use some Red Loctite and heavy grease as they suggested). No squeaks so far or rattles, etc from the front end. Feels pretty solid. I didn't have to take off the wheels, just drove it up on ramps.
• There was NO additional quirks in my case from the mod as far as steering vibration, losing steering alignment (still tracks straight), etc.

CON:

• It's pretty expensive, IMO. Could be $100 cheaper, tbh.
• One small issue is when braking, because there is so little give now in the front end, if you brake and drive over a small bump, the front end will sort of "skip" over the bump, vs. staying planted. It's a small tradeoff for more road feel and some other performance cars I have can do the same thing. In a way, it's OK because it's telling me there was a road defect there which is the point of more road feel.
• I'll give Lexus credit, they did manage to build the original LCA bushing amazingly well in that it really isolated the driver from EVERYTHING. Definitely a very Luxurious feel, but truly it was like you were driving an appliance. However, if that's the quality you like about it, then stick with it. It's pretty amazing really how they managed to dial out NVH.
• I'm not yet 100% sure, but I do think it's a bit more responsive and you can expect a bit more steering wander if going over uneven surfaces. But that's just to be expected.

I have an E46 BMW and every time I get into that car, I'm just impressed by how communicative the steering is, so it's sort of been my benchmark. Since getting my ISC, I've been trying to get as close to that feel as possible. While the power of the stock IS350C never really left me wanting more, the handling and steering traits were truly abysmal for anyone that actually enjoys driving.

The F-Sport suspension, Sway Bar upgrade, ISF Steering ECU and now the RR USRS brings me a bit closer to that feeling, minus the BMW reliability issues!

AMIRZA786

Good review. It definitely stiffens the front end, but I think yours much more due to you having F-Sport suspension, which is stiffer than the stock suspension. Pretty much most of what you describe is what I experienced after installation. Imperfections in the road are much more pronounced and I feel handling has improved, but that may also be a combination of installing F-Sport Sway bars and an ISF steering ECU

lockedlex

I had about 18 months on the suspension upgrades before the USRS install. So the observations made pertained just to the specific changes felt after the USRS was installed, but no doubt, I'm sure the stiffer suspension brings a bit more road feel into it than having a stock suspension (though prior to the USRS, it never did that hop/skip while hard braking over bumps).

I'm happy with it, I think if I had to pay for the install though, it would have been a little too pricey for the actual benefits gained.

I'd say it's fine stock, if you don't really drive your car/aren't a "driver" or haven't owned Porsches/BMWs and miss that steering.

AMIRZA786

They definitely are expensive, but I bought them cheaper a few months back probably because the pandemic had started. They were worth every penny as it took the sloppiness out of the steering I was getting before. But honestly if I had known you could install LCF bushings for 3x less, I would have gone that route.

One thing, you will have to re grease them in a few years as the polyurethane will begin to squeak

lockedlex

That's the weird thing actually, my steering prior had no sloppiness, it was actually very tight with no "on center" dead feeling. It was and is still very sharp. I can't say it made the steering feel any better in that respect, but I can definitely "feel" more things. I'll have to remember about regreasing them!

AMIRZA786

I have a 2010 IS350 Sport, and although it has slightly stiffer suspension, the stock LCA bushings were classic Toyota soft rubber to isolate the driver from the road. The steering kind of reminded me of my Camry, except it had this dead spot where the steering would literally go "dead" when going on long trips and making steering corrections. Not dangerous, but annoying. I never experienced that in any of the 6 Toyotas I have owned over the last 25 years (most of them were fluid driven PS systems), and I basically think it's an overzealous VSC. I was able to fix that issue by swapping out the stock PS ecu with a 2010 ISF PS ecu. It still happens on longer trips when I'm going at higher speeds, but it happens less and is almost unnoticeable now. Since you have a 2014, they probably fixed the issue by reigning in the VSC. Also since you have F-Sport suspension, things are a bit tighter.

For those of us that own 2nd Gen IS350's between 2006 and 2012 and drive more spirited, the three mods that are a must are 1) F-Sport sway bars (front and rear), 2) either RR Racing or Figs Engineering Polyurethane LCA bushings (or RC-F LCA Bushings), and 3) an ISF Steering ECU. After doing these three updates, the handling characteristics completely changed.

BTW, after installing the LCA bushings, if you have not done so, you should get an alignment. After I installed my bushings, my alignment was slightly off

lockedlex

That must be it, maybe 2014 changes of some sort. Yeah, I'd never had any dead spots in the steering (that includes prior to upgrading my Steering ECU to the last ISF version).

Yes, I think any suspension rework could use an alignment. My car still tracks straight (steering wheel is dead center on the road and was aligned by Lexus in 2019), which was the case before and after the install. So that plus COVID, I'm not in any rush to do it. Actually, I kind of want to wear down these tires I have (came with the car) and go with another brand, so I'm probably not going to align it. RR does state that it's not necessary to align it if it was in alignment prior and doesn't exhibit any issues.

zzzzyy

quick question, the fsport sway bar on the site mentioned they only suit for is250 06-13 and is 11-13, i got a is350 2007, just being confused does it fit my car?

AMIRZA786

Hello. I believe both use the same sway bars, so you should be fine. You may have a hard time finding them new, as Lexus has discontinued the F-Sport accessories for the 2nd gen

zzzzyy

sad, it means I have to pay 1000 bucks for Cusco one. I'm not sure if the Chinese-made sway bar is better than the stock or not.

PewPew7

iTrader: (1)

They aren't. 2 differences for the front sway bar

1) Mounting points for the sway bar links are in a different position
2) Mounting for the bushings is also a bit different.

So consequently, 2009+ can use both, but if you choose to use a 2006-2008 sway bar, you will need to get 2006-2008 sway bar links otherwise it will not mount. Bushings will be fine.

If you are 2006-2008, you can only use 2006-2008 sway bars because the bushing stops for the 2009+ are farther apart, preventing you from mounting the bushings. If you shave them down (not easy) and get 2009+ sway bar links, you still need to purchase 2009+ headlight level sensor (if you have hid lights).

I know this because I own a 2007 Is350 and I bought a 2009 f-sport front sway bar and I encountered these problems, had to sell it.

The rear sway bar is the same for all models with possible exception to the awd (not clear on that).

If you have a rear sway bar and looking for the front, an alternative is the ISF front sway bar which reports to be identical to the f-sport 2006-2008 front sway bar.

PewPew7

iTrader: (1)

Not necessarily. If you can find an ISF front sway bar (part number: 4881153070), it is reported to be identical to the f-sport front sway bar (2006-2008).

I just bought one for my is350 2007:
https://parts.belllexusnorthscottsda...881153070.html