I recently took my 3rd gen IS350 F Sport to an autocross. Was running Conti ExtremeContact tires. It was my first time and just ran it with traction on and auto-shifting (no paddles). Car was competitive for its class. But man, it understeered like crazy and the traction control even in S+ is waaaayyy too invasive IMO. I had an instructor ride with me for a few of the laps and he would go "floor it" and well ... yeah, it's floored already buddy. Say hello to traction control LOL. Tires were pretty beat up after the day in terms of rolling onto the upper sidewall.

I used to run MPSS on my 2nd gen IS and I think the MPSS is much better in dry. But I recently got this IS and it came with Conti's, so that's what I'm running for now. Car was 100% stock including brakes. I also did some laps as a passenger in a couple of Vette's, and the performance difference of the cars was startling ... yeah, no surprise, but still... those cars were a.w.e.s.o.m.e.

Had a great time and hope to find time to do more of these in the future... If you are in the Dallas area and do autocross hit me up... would love to get a few of us together for one of these events!

G

 

Did you hold the traction control off for 10 seconds? That usually disables most of traction control.

The only issue with the IS in terms of autocross is that the consumables are so expensive. The IS eats brakes yearly for me

 

I've seen in reviews where the IS is pretty tame with TC off - try and let us know.

Also, good on you for representing. Whenever I go to Cars and Coffee, I'm pretty much the only new-ish Lexus there. Time to make some noise in the community.

 

Glad you had a great time! Looking to autocross my IS next month. Quick question... our cars are considered D Street Class right?

 

Yep. DS. Same as wrx and brz.

 

I didn't touch tc at all. I just wanted to focus on the course this first time event without also learning the car and the breaking point of the tires. I was really tempted by the end of the day though

 

Thanks. I was the only Lexus present. Looking forward to getting more competitive over time.

 

i was wondering this the other day. i haven't even tried. can TC be turned all the way off? I know i can do it at a launch, but not sure if that's trac AND stability? or just trac.

and yes consumables on this car are crazy. normal grocery store commuting wears F sport brake pads in 10-12k miles. i cant imagine what an autocross session would do.

this car is too heavy for autox though. but i'm sure still fun.

i did an autox once in another car.. and there was a 1st gen Lexus IS manual there (fully bone stock) absolutely destroying nearly everything. that includes a ton of miatas and a GT3. the only car that did a faster time was one miata. but man that guy could drive. made me want to get an 1IS.

 

So ... according to the owners manual

1. Pressing the TC button once turns off just Traction Control, until speed is increased -- and then it comes back on automatically. Basically this mode is just to get the car out if stuck in the mud/snow.
2. Pressing the TC button for over 3 seconds turns off both Traction Control and Vehicle Stability Control

Definitions:
TRAC = Traction Control = helps keep the wheels from spinning when starting from a standstill or accelerating on slippery roads
VSC = Vehicle Stability Control = Helps the driver control skidding when turning or driving on slippery roads
EVSC = Enhanced VSC = Coordinates ABS, TRAC, VSC, EPS (elec power steering) = controls steering performance for stability when driving on slippery roads

So while the manual doesn't say that turning off TC for 3 seconds shuts off everything possible, it seems like it shuts off the main nannies.

If anyone has more intel, feel free to add/correct.

BTW - regarding the IS being ideal (or not so ideal) for xcross ... totally would agree it's not the best car based on my experience. BUT ... that said, in truth, I would be fine driving just about any car on a xcross circuit. For me it's about the fun factor of doing the course and competing with myself to lower times. There will ALWAYS be better/faster/funner because I don't have the budget or even preference to go invest in a track weapon and then tune the crap out of it until its perfect. And sure-- for $70K you can go buy a used BMW M1 or for less a used Z06 or similar and get most of the way there... but I just am not in a position to do that.

 

+1, I have driven in a snowy parking lot, and it doesn't really let me do much of anything till I have done either A) the pedal dance or B) held down the TRAC button for 3 seconds. I tried both, didn't seem to make a difference. If I did neither, the VSC would activate the brakes to try and keep me from sliding or drifting.

And also, I agree - it's not all about speed. I have driven faster cars, but that doesn't mean they were more fun.

 

Alignment.

You really need to dial down the rear camber on the IS platform. They are set to under steer form the factory. Either lower the camber on the rear or raise the front camber with an aftermarket camber arm. That should do the wonders.

 

If you want to fix the the understeer you can get a stiffer rear safety bar.
if you want to go cheap just buy stickier tires for the front to balance the front/rear grip.

 

going square also works too.