I've been autocrossing on and off for 3 years now in D-Stock with my '07 G35x. I got to thinking and realized I've never really taken into consideration that fact that I've got the advantage of all wheel drive into my driving.

What kinds of things can I do as far as driving line, car setup, etc... to potentially improve my lap times with AWD in mind? My limited understanding is that the big advantage of AWD is being able to accelerate sooner and harder out of corners due to the extra traction, but I don't feel that at all. I mostly just understeer if I try to push out too early through turns.

Thoughts? Thanks in advance!

 

In my experience, AWD is most beneficial for Pro-Solo's (off the lights), as well as when you're autocrossing in the wet. In such cases, it gives you a big advantage and is worth quite a bit of time.

In the dry, the benefits are less pronounced, especially you are also carrying more weight than a RWD G35. Personally, I wouldn't change my lines too much if driving an AWD car. I would also err on the side of slow in, fast out with the car though (late apexing).

What kind of tires are you running? And have you added a swaybar? You can also make your car understeer less via air pressure, shocks (if adjustable), and the swaybar.

 

I definitely see a huge difference in the wet because I can induce oversteer a little bit and feel like I can push harder and clean up my lines. My raw time for the day ranks WAY higher when it's wet than in the dry. I typically late apex, mostly because I have trouble doing early apexing correctly, but that's just a lack of experience.

Right now I'm running Kumho Ecsta SPT street tires on my heavy 19" wheels (245 wide). I've installed the RWD G35's rear sway bar which is 24mm vs. the X's stock 17mm bar. I still understeer in the dry so I've been trying to decide if I want to get an aftermarket (adjustable?) rear sway bar to stiffen it up even more, and if so, which one to get.

I haven't really played with air pressure much so that's a good thought. More pressure in the back I assume would make it a little looser. Any idea on what pressures to start out trying? I typically run around 37-40psi cold all around.

I'm limited with what I can do as far as the car so I can only have 7.5" wide wheels, 245mm wide tires (going to be running Star Spec's next season most likely), 1 modified sway bar, and a cat-back.

 

As a caveat, i mostly drive on road courses, so not sure how things translate to autox world. I also drive the fr g35, not awd.

The benefit to awd is that you can accelerate like mad going out of corners. The line is more similar to an ff line with relatively late apex as opposed to fr line. Your goal is basically to get to the apex at the proper speed as quickly as possible, and be able to stand on the gas right at the apex. Chose your apexes accordingly.

With the attesa ets, if your having terrible understeer, you are probably overspeeding into corners. Spend some laps(sessions?) Testing different driving styles. First brake harder and earler, turn in, and focus on standing on the gas at the apex. If you find yourself not putting any gas as you get to the apex, you oversped into the corner. Basically as soon as your foot comes off the brakes, it should be back on the gas a little. If you find yourself coasting and scrubbing speed to get to your apex, you oversped into the corner. You should be pretty neutral coming out of corners, but as you accelerate out of a corner, of course your car will start carving a bigger circle, its just physics. If you run out of track, next time apex later. Also apexing not just about position of your inside front tire. Also about the yaw of your car, basically what angle it is on the track. If you overspeed into a corner, even if you can scrub speed and get your inside front tire at the proper apex, your car isnt facing the right way and you still cant get your car to accelerate early.

Also consider practicing trail braking, braking all the way the apex, though this is a pretty difficult technique (i know how it works, but not quite there yet). Good thing is our brake system wont let you spin while trail braking, but itll probably kill some of the rotation.

I dont know about autox rules but are exsta spt the best category tire you can run? Try to go to like extreme performance or uhp if you can.

Your tire pressures sound too high, but that may be right for the autox world when your tires dont heat up too much. You can find out your optimal pressure by downloading harrys lap timer if you have an iphone or trackmaster if youhave a droid, and doing a skidpad repeatedly, letting your tires cool and changing your psi. Then finding what gave you maximal lateral g.