[cartman300]

I was just wondering if any of you have driven the IS hard, either on the street or the track and woulf like to know what your conclusions were (oversteer,understeer).THanks!!

 

[sacremon]

Understeer, and lots of it. That's one of the reasons I got the TRD sway bars.

 

[ckolsen]

I think it's misleading to say the IS300 has heavy understeer. It's not like driving an Accord or Acura TL, which understeers on slow speed corners, the IS300 is neutral until you approach the limit, THEN it understeers, but it's still better balanced than any FWD car I can think of (except Type R). In fact, even at the Lexus event, it felt neutral to me, but the course was soaked.
Plus oversteer is easily provoked by throttle. Try THAT in a TL.

Originally posted by sacremon:
Understeer, and lots of it. That's one of the reasons I got the TRD sway bars.

 

[ISLover]

Definitely understeers a lot.

 

[SPiFF]

Like any stock car the IS has a good bit of understear. Though you can use the throttle to get the tail to move around a bit untill the auto tranny does seomthing to stop your fun. The CG is a little high and the spring rates are a little too soft making the car feel uneasy in fast corners.

The suspension design is top notch and the chasis is awesome. With some aftermarket parts and a manual tranny the car will be perfect.

 

[cartman300]

Originally posted by sacremon:
Understeer, and lots of it. That's one of the reasons I got the TRD sway bars.

sway bars in the back? If you add sway bars in the front that'll only make it understeer more, right?

 

[cartman300]

Originally posted by SPiFF:
Though you can use the throttle to get the tail to move around a bit untill the

.

what does it do?

 

[sacremon]

sway bars in the back? If you add sway bars in the front that'll only make it understeer more, right?

TRD racing sway bars are 50% stiffer in front, 100% stiffer in back, so they tend to counteract the understeer.

 

[DownShift]

I've actually noticed something different than what's posted above. When taking a corner at higher speeds and lightly letting off the gas, the back end tends to slip out, and I have to counter turn the steering wheel. (Looks pretty damn cool). It can getting annoying. It may also be due to the Yokohama A520's I just put on the car a week or two ago. They do understeer in longturns which has been pretty scary too!

 

[marke1]

Originally posted by DownShift:
I've actually noticed something different than what's posted above. When taking a corner at higher speeds and lightly letting off the gas, the back end tends to slip out, and I have to counter turn the steering wheel.

I believe that is one of the ways to induce oversteer in cars, especially those with RWD. I think it's called "trailing throttle oversteer".

 

[hrana]

Actually, that technique is what got a lot of porsche drivers in bad siuations... even killed. Do not lift in a turn unless you know what you are doing.

 

[Risk3233]

In my driving experience, the factory suspension setup can be described as fairly neutral, w/some understeer in the corners.

With the TRD race sway bars installed and increased tire pressure front and rear, the car moves into a more neutral handling style.

I think the LSD in conjunction w/the TRD sway bars creates even more neutral handling.

IMO you can get most RWD cars to oversteer w/strategic application of the throttle. This also holds true for the IS, but I wouldn't say its PRIMARY drive characteristic is oversteer.

 

[ckolsen]

I guess the rear sways reduce roll of the rear end? My '95 325i is very neutral - if I corner too fast, the back end comes around rather than understeering, though sometimes it understeers, I'm not quite used to why. Newer BMWs understeer if you corner too fast, like the IS300 - to make them safer to drive fast I guess.

Originally posted by Risk3233:
In my driving experience, the factory suspension setup can be described as fairly neutral, w/some understeer in the corners.

With the TRD race sway bars installed and increased tire pressure front and rear, the car moves into a more neutral handling style.

I think the LSD in conjunction w/the TRD sway bars creates even more neutral handling.

IMO you can get most RWD cars to oversteer w/strategic application of the throttle. This also holds true for the IS, but I wouldn't say its PRIMARY drive characteristic is oversteer.

 

[LexusIS886]

Tighter rear suspension induces oversteer while tigher front suspension induces understeer. By adding a sway bar you stiffen the rear chassis and thus make the car head towards the oversteer side. Depending on your driving, what kind of races you participate in, etc determins what kind of suspension you should have. Autocrossers usually go for a more oversteer car while road racers usually go for a neutral effect. Most stock cars understeer for safety purposes.