OK so I've gone through the site for a bit and have not seen what I'm looking for. I want to fix the wallowing numb feeling in the stock SC430 suspension. I'm not certain if this is just a good alignment away or what it will take to make the car more confidence inspiring. I'm really not interested in lowering the car if I don't have to. I don't believe the condition is ceter of gravity related. I have a 2007, Dunlop RFT tires all with the as delivered set up. I'm use to German cars (Mostly AUDI and Porsche) and I just find it hard to believe that there is not something out there to make this not feel so disconected. What have you all tried to correct this and how has it worked? It there a magic alignemnt setting, tire fix, shocks....? I realize this is a subjective thing so please provide details as to your results.

 

First thing first-tires.
Next up would be quality sway bars-the preferred here are the Daizens.
On top of that would be a nice set of coilovers such as Teins. Forget the springs and shocks setup. Not something for a caliber car such as this. I believe the SC430 classifieds has a set listed.
With the above the car will still not be in Porsche terrirory-hey it's a Porsche, but right in the BMW ballpark minus the steering feel. Keep in mind Bimmers are designed to feel the way they do. This car is designed to feel the way it does. Some prefer the later, others the first.
I like the sporty feedback myself but had to weigh all of the options.

 

i agree with lee. you can make the car to handle much better with the setup lee mentioned, and you get more road feel as well and less of a numb feeling.

however if you are looking for the kind of road feel the porsche or audi or bmw give you, then that's definitely too hard for this car. it's fundamental setup and lexus is "good" at that. just think of it this way, give you a bmw and it's pretty much impossible to make the road feel of that the same as lexus

 

If I can get this thing to handle at least like my wifes 2006 IS250 then I would be happy. I relize the Lexus steering dampens out a lot of road feel and this car feels like it has an extra turn lock to lock. Is there any other steering box available for this car?

Those who have made a tire switch have conventional tires made the suspension respond better? Most seem to only talk about the ride improvement by ditching the RFTs. These tire have to be heavy and add to the unsprung weight. I know on my last car and Audi TT Roadster that the Michlin sports were razor sharp on handeling but had no tire life. The Conti's I replaced them with road and wore better but just did not have the responce and feel of the Michlins. These feel more like the Conti's so I wonder what a more agressive tire would do to the feel (Plus bring down some of the weight). When I was at the Taste of lexus last month the Dunlop folks said the softened the newer RTF to ride better on the 2006-2007. Have you guys driven a 2006-2007 SC out on the road? Did it seem to feel disconected?

The dealer here also puts nitrogen in the tires, but at the factory preasure. I generally like to run a higher preasure than the label in the door and follow more the tire manufactures recomendations then the car manufacturer since the car manufacture generally goes with the least common denominator when settting this to meet all the tire brands they install needs. I really wonder what bumping the preasurs up 8 psi would do?

Seems to me that alignment could help a lot here. I've seen on several cars big gains with the right setup here. I know that most of the time alignment tolarences are generally several multiples over the specification. Has anyone experimented here?

I'd like to get some feed back on these changes before I change out the sway bars and shock/spring set up. Maybe even better bushings would help. I think with the exception of the slow steering and tires that a little tweeking would vastly improve the handeling without killing the other aspecs. How close is the 2006 LS suspension to the SC? This car seem to do much better with less tire so if they are close there may be some hope there.

 

in general I think the stock sc has a floaty feel to it. I felt a dramatic improvment when I installed my sways, then droped the car and on rims If you plan on getting new rims then I wouldnt even bother changing out the run flats. if your going to keep them then switch out the tires. definently get the sways and maybe some springs or coil overs. I would let u ride in my car but I cant really hit curves too fast, I am too low and it rubs LOL

 

I hate the stock suspension its to smooth for me and cant take corners hard, you gotta slow down allot

 

Other than Tein and Tom's, there are some other coilovers designed for SC430.

RS*R



Phoenix's Power (Quantum)



Answer (Bilstein)



AutoCouture



QuestPower (Ohlins)




Some pics to show you the same car with different drop.

 

If you don't want to spend thousands in Tom's STB and brace set.
A company called SPR in Taiwan make these for under $500.

 

running tyres at the following pressures seem to eliminate the floaty sensation and improve the road feel in the SC 430s:

Front 30 psi
Rear 43-45 psi

 

OK, This is all good input. So I did a little test with my dealers diagnostic tech along. We experimented with tire presures and arrived at what I feel is the optimal (At least with the 2007 SC430 stock setup w/Dunlop RFT) tire preasures (with the nitrogen) of 42 psi all around. My original front preasure was 32 psi and the steering was very heavy. We tried droping it down as suggested and it only became heavier. Between 39-42 feels the best with out killing the ride (Even over train tracks which is some thing I need to cross daily so it is why I'm not a big fan of lowering the car). The car is worlds better. I think with a sway bar change is would be just about right. Now if I could find a steering box that was about a turn quicker lock to lock it would be perfect. Anyone know of a fix for this?

 

this is interesting. i have tein cst edfc and use 11 front 6 back most of the time. also considering swapping out the rear springs for stiffer ones. has anyone tried this?

 

No but I did order stiffer springs for my fronts. I have Tein CS. It has not come in yet.

 

a very good alignment helps alot.

 

Do you have a suggested setting spec?

 

depends how low you go. Let me know what you plan to do and I can direct you to a good alignment shop