l3xus

Hi,

For those of you who replace the run flat tire, do you see a big difference in the car handling?

I am thinking of replacing the run flat w/ all season tire hoping that it will make the handling better.
Right now, I'm hesitant to drive the car fast. The car doesn't seem to stick to the ground when driving fast and the steering wheel feels light.

Do you think replacing the tire will help? Or should I get a new set of wheel and tire. I've been told by my dealer that the stock rims is heavy.

My car used to pull to the left and right, my dealer fix it by adjusting the tire pressure. Apparently the pressure wasn't even on all 4 tires.

But I am still not satisfied with the way the car handles.

Thanks for your help!

AB
02 silver/saddle

LexusSC430

First, let me start by saying the steering in the car is very tight and is as good as anything ive ever driven. I dont know how anyone could call it light. If you mean in the sense that the car seems light then thats a different story.

I dont think the car handles bad at all, its not a sports car. The run flats arent the greatest handlers but they are pretty decent, much more so then I think all season radials will be. Now if you put a set of Z rated tires on then thats a different story. But then you have no spare, and half the mileage of a normal tire. I would just leave them, it really is not that bad and the alternative is either sacraficing a spare, ride quality, saftey in rain and etc or an expensive one. I personally have 19" with 295/30 in the back, but thats $6000 and i have no spare and i dont drive the car in the rain.

Exhaloprez

I replaced the runflats with Bridgestone Potenza SO 3's and the car rides so much smoother!!! It no longer rides as if I had four boulders as tires. Even the dealer (from whom I did not buy the tires) commented that he agreed with my decision. The car seems to handle better but it may be my imagination. I drive in 4th and on power around the city and it has made the car a burner.

l3xus

LexusSC430 and Exhaloprez,

Thanks for your comments.

I guess you're right. SC430 is not a sport car, it's a touring car. I used to have a boxster and S4. Maybe I shouldn't compare them.

The steering feels light only during speed above 50 mph. It feels I can move the steering too easily. The steering also slightly to moved to left or right by a small bump (and during braking). This is what makes me affraid driving it fast. I have to grab the steering wheel tightly.
My dealer said it's because the rim is 18". I don't buy that, I used to have 18" rim and this never happened.

Exhaloprez, how much did you pay for Potenza SO 3's? Did you have to disable the tire monitoring pressure.

If replacing the tire will help the handling and eliminate the "moving steering" problem, I think I'll pursue that road.

Thanks! and btw other than those problems, I have no complain on this great car (covertible + luxury)

AB
02 Silver/Saddle

Exhaloprez

I paid $235 per tire and I do not believe they had to disable the tire pressure monitoring.

evictor

Exhaloprez, where did you get your new tires?

l3xus

Exhaloprez,

I saw your post in the Wheel forum section. It looks like you're thinking of getting a new wheel.

Is the stock rim too heavy? or is it the style?

I'm thinking either replacing the tire or buy a new set of wheel/tire.

Do you know if you can replace the wheel/tire yourself? Or do you have to do it through the dealer because of the tire pressure sensor?
How much did it cost you to have the tire swapped?

Have you checked www.tirerack.com, I saw a few rims that looks not bad: Mille Miglia Action, Mille Miglia Evo5, Mille Miglia MM11-2, or Moda R3.
Those rims don't look flashy tho. I guess it depends what you want.
Lowenhart LD1, BR5 and LR5 are also nice rims. I don't know how much they cost.

I'm planning on going to the local mod shop and look at their cataloques. I'll let you know if I saw anything good.

AB
02' Silver/Saddle

Exhaloprez

I went to Chatsworth Tire Company on Devonshire just east of Topanga Ave. in Chatsworth, CA. They do not swap it ou. I am hoping to get wheels/rims but not from a dealer.

antigeek

You guys have it right. It's not a sports car. It's a sport luxury car. I've had my days when I'm disappointed that it won't take a cloverleaf at 60mph (it'll do 50 with a little squeal & scare). But it's FAR outweighed by the effortless, utterly enjoyable smooth but responsive ride.

My '93 SC400 was the same way: tight steering (especially with Dunlop Sport 8000s) that was a dream for changing lanes, but a smooth ride. I admit that there were some days when I felt like the ride was a little rough, but was quickly reminded of the Lexus' quality whenever I had a passenger. No other cars with that performance come close to its smoothness.

I've come to respect those who want to change the ride. Finding the right tires for any car that can perform is a difficult and VERY personal choice. I tried going back to the Goodyears that the SC400 came with once. I got a smoother ride, but I lost the steering response -- so I made a made a trade-off to get what I wanted most and went back to the SP8000's.

The SC430 is a well-integrated machine, as are all Lexus'. One modification does not fit all. If it's possible to describe the differences between rides with different tires, I think it'd be a great sub-forum for this group.

Thanks, all.

WJSOLOMON

Originally posted by l3xus:

"For those of you who replace the run flat tire, do you see a big difference in the car handling? I am thinking of replacing the run flat w/ all season tire hoping that it will make the handling better.
Right now, I'm hesitant to drive the car fast. The car doesn't seem to stick to the ground when driving fast and the steering wheel feels light." - AB


AB - I put slightly over 1,000 miles on my R. F. Tires, and had them inflated up to 45 psi from the Door Label's Suggested 33 psi, when I made the "Run From Ohio" back in an earlier Post in mid-December (see: "RUNNING LIGHT COMES ON AT 115 MPH!"). Actually, on the Intersate Highways, after getting used to it's characteristics for 1,000 miles, I found the Car's Handling and Cornering quite predictable at Speeds over 100 mph, on DRY Pavements. Actually, it handled much better in Heavy Rains, with absolutely No signs of trying to "Hydroplane" on the rain soaked Interstate, than I ever imagined that it would.

Swithing to the Lexus Suugested / Approved "Bridgestone Winter Sport II (Dedecated) Winter Tires", and on additional OEM SC Wheels, as per my Post in late December (see: "WARNING - DUNLOP WINTER SPORT II WINTER DRIVING TIRES BRING LOW INFLATION WARNING LIGHT ON AT 142 MPH!"), I drove them over 3,000 Miles down and back from Indy to Sarasota, Florida over the Christmas Holidays. As opposed to the OEM R.F.'s they are a Lot Quieter, and provide a noticeably Softer Ride. They are also Extremely Competent at Speeds up to and over 100 mph, but seem to have much more of a "Comfort Zone" at 75 - 85 mph. As good as they are for High Speed Driving in inclement weather, the car still slid down my concrete driveway with the brakes on, with just 0.5" of wet snow!

Other Drivers have shared herein with their Posts, that they seem to be leaning more towards Michelon, Bridgestones, and Pirrellis, in a High Performance "All Season" (as opposed to "OEM" or "Winter") Driving Tire, as they eventually move away from the Harsher Riding OEM R. F.'s.

Back Track through the various Posts on these Performance Tire Reports, Print out some copies for your file, then enjoy shopping and investigating all of the interesting "Owners' Reports" from the various choices available for our SC 430 with the OEM 18" Wheels, from the "TIRERACK.COM" Web Site.

A kind "word of wisdom" - monitor your tire pressure once or twice a week on the OEM R. F.'s, especially if you've run over Pot Holes or other pretty severe Road Bumps. These puppies seem to like to Leak Air, more than most, and if your Four Tires are not all at the Same Level of Inflation (33 psi Minimum - 51 psi Maximum), the car simply will not Handle nor Preform in the Tight Cornering Maneuvers, as it should, and was Designed for.

From my own experience, it may not give the remarkable "Feed Back" through the Steering and your "Seat Pucker" as a BMW with the Upgraded "Sport Package", but learn to trust it's uncanny ability to get you into and through some of those High Speed Curves on and Off the Interstate Clover Leafs, at increasing increments of speed. If you've got the nerve and the skill levels, it's got the balence and Torque Steer to keep you covered, and cool you down, when the beads of sweat momentarily brake out on your forhead!

You may want to experiment with running around at increased inflations of 5 psi per trip, until you find the Optimum Inflation for your particular Car, and your own individual type of driving / handling style. Even at the Maximum Inflation of 51 psi, the very nature of the STIFF Side Walls that allow us to "Run (them up to 55 mph) Flat", will not, in my personal observation and opinion, give them any more of an unbearable ride, than at their Standared Recommenced Inflation (on the Driver's Door Jamb) of 33 psi.

"Soft Bumps!"

:eek:

l3xus

WJSalomon, thanks for your suggestion.
Last time, I did asked my dealer to increase the pressure up to around 42psi. The ride was harsher, but it slightly improved the handling.

I just replaced my run-flat with S03 today. The new tire seems more noisy, hopefully because it's still new.
The car seems to handle and ride better now. I'm hoping as time goes on, the tire will be more flex and the handling will get better and better
The car still pulls (less than b4) to left or right on rougher surface especially during braking. I guess it's due to the width of tire.

After a couple of days/hundreds of miles, I'll let you know if the handling improves greatly or not.

AB
----------------
Silver/Saddle

WJSOLOMON

Originally posted by l3xus:

I just replaced my run-flat with S03 today. The new tire seems more noisy, hopefully because it's still new.
The car seems to handle and ride better now. I'm hoping as time goes on, the tire will be more flex and the handling will get better and better


AB - Happy to hear that your RF change improved the Ride and
Handling charactaristics of your new car. If the Tires are inflated Too High for simple local / around town driving, it could be the reason it "darts" to the right or left when encountering minor road irregularities. Try dropping it to 33 - 35 psi, just to see if it eliminates the darting right or left, for every day driving around town. For the longer road trips on the Interstates / High Speed Touring, it rolls a lot more efficiently at the Top End, at closer to Maximum Allowable Speeds designed for the particular Upgraded Tire that you're using.

As many things in our lives, these Tire choices end up being a series of "Compromises": High Speed Performance on Dry Pavements / Heavy Rain / Snow / "Black Ice"; Noise Levels; Tread Life, etc.

So Many choices. So little time.

Soft "Chops"!

Exhaloprez

My dealer yesterday placed the retrofit (bushings) in my car. Now, with the conventional tires and the retrofit, the car rides like a dream!!! You still feel the road (good) but the jarring is gone. My car is a pleasure to look at and now to drive.

LexusSC430

The tires will be much noiser, the S03's I mean.

As for the darting to the left or right that is due to the power of the brakes. Im sure it only happens from higher speeds rather then from, say, 10mph. It could also be attributed to road surfaces as well. Its normal in a car like ours. If the car had the stiffest supension and was slammed it would do this much less, but think of a tractor trailer. Its simple physics, objects in motion tend to stay in motion....so when you slam on the brakes of a 3800lb vehicle it tends to not play nice [and straight]. Oh well hope this lets you worry less and enjoy the car more.

1NICESC430

For those of you who have replaced your RFs with conventional tires and have not "upgraded" your SC with the spare tire kit, what is your plan if you DO get a flat?

Assuming you have a can of it, does Fix-A-Flat really work?
Will Lexus honor the roadside assistance agreement? After all, you don't have their spare or their supplied RFs.