06-01-2018, 01:14 PM | #1 |
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Preparing for first autocross
I'm preparing for my first autocross this month. Aside from being nervous about embarrassing myself on the course, I'm also afraid of forgetting something important or running the wrong setup. Any input on these newbie questions is appreciated!
What tire pressure should I run? I have the stock PSS tires (225/40/18 front and 245/25/18 in the back). I've got a 6MT. Do most of you run in Sport+ with DSC off? I've got 12,000 miles on the car. Should I do a brake flush before I go? What should I bring with me? I don't have a spare tire so I'm guessing there's no point to bringing a jack or a breaker bar. I was thinking about bringing: 1. Torque wrench (good idea to make sure the lugnuts are torqued between runs?) 2. Socket for the lug nuts and wheel lock (17mm right?) 3. Extra coolant (which should I bring? can you mix the OEM coolant with others?) 4. Tire pressure gauge 5. Helmet 6. Food and water. Thanks guys. Last edited by Blue2; 06-01-2018 at 02:56 PM.. |
06-01-2018, 02:11 PM | #2 |
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Autocrossing does not put all that much stress on a car as time trial competition or a track day so relax. Your brake fluid will be fine as is for your first few events and you aren’t going to need to add coolant unless you have a known leak. I have done track laps at 106 degrees without losing a drop.
The M235/240i is not a “natural” for this activity out of the box: it’s heavy, under-tired, and alignment limited. For the OEM tires I would recommend pumping the fronts up to match the rears at 38psi cold then use your tire pressure gauge to balance right to left on each end at the end of each run (bleed down the higher side to match the lower. Your fronts should build pressure more than the rears. I have the 8 speed automatic but would still recommend running in Sport+ mode. Unless you are going to be changing wheels at the event there is no real need to bring a torque wrench and socket (just torque the lug bolts to 110 lb/ft before you leave home. So, bring a tire pressure gauge, helmet, and food & drink plus a roll of painters masking tape to make whatever number you end up getting assigned. Most of all prepare to enjoy the experience! |
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06-01-2018, 02:46 PM | #3 | |
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06-01-2018, 03:51 PM | #4 | |
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Tire pressures Start at normal street psi. They will quickly come up to around 40ish psi after a few runs. Get comfortable do a few runs, and then check the pressure. The sweet spot for super sports for me is around 35-36 psi all around. This does compromise outer shoulder wear though. As pss warm up, they will start to flex on hard turns and eat the shoulders. You can fight it by upping psi to around 38 all around, but then your grip is compromised. I went through pss in 2 events and about 1500 miles. My next tires will definitely be r comps accompanied by some camber. Drive Mode I'm 6mt too and I'm always dsc off. As long as your auto x is safe (no poles and stuff like that) you should learn how the car performs at its limits. Being able to know when the rear end will step out and the correct it with throttle modulation will help you in the long run. Even sport + will cut power if you get enough slippage. Auto x is the place to spin out, once again only if there is no poles around. Brake Fluid You should be fine with stock fluid. I think its a good idea to go in with the car stock and upgrade as necessary. I boiled my fluid at my last auto x. The course is unique though 50mph+ for most of the course. Some people can reach triple digits. Stuff When I do events I bring: Torque Wrench and a 17mm (check torque after 3 runs or so, good for the rest of the day) Cooler with food and drinks, driving while hungry sucks. Quart of oil, You shouldn't need coolant. You really shouldn't need oil either, but it's nice to have. Tire pressure gauge. A nice one that you can read pressure and release at the same time. I have a $30 one off amazon. Helmet. Get your seating position comfortable before you go with a helmet on. Masking tape if you're concerned about running over cones. Most cone marks do come out with wd40 though. ______________________ Other than that, just have fun. I couldn't sleep the night before my first event, I was so excited.
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06-06-2018, 12:17 PM | #5 | |
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I had to pump up the front to 48 psi when hot to stay on the thread block. Rear was good at 35 psi. |
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06-06-2018, 01:33 PM | #6 | ||
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Congrats on deciding to autox and actually planning for it! You'll have fun and no need to worry about being fast or embarrassing yourself (it will happen sooner or later anyway since nobody starts out as a perfect driver).
You should just shoot for 35psi hot for now. Lower your pressures 3-4 psi when you arrive and check them after each run to see how much they increase throughout the day. Since this is your first autox, I recommend you not worry about tire pressures and focus more on learning the course and your car. Trying to figure too many things out on your first time will only complicate and confuse you. You should always run with traction control off, so just press and hold the DSC button for 5 seconds. No need to do any flushes or bring fluids/oils. Autox isn't going to boil your fluid unless it's just really crappy or you're excessively riding the brakes. You're not going to lose oil or coolant unless you already have a leak (and if you do, you shouldn't really be on the course spilling that crap anyway). You don't really need jack & stands or tools, but it's good practice to have them just in case you need to lift your car (rare but things can break). Torque wrench should be used to check your lug bolts once you arrive and the wheels have cooled down. Don't check in between runs because you won't need to as long as you checked in the morning and you shouldn't torque things down when hot. Bring a tire gauge and a compressor since you'll be checking pressure a lot (before event starts to bring down psi, in between runs to check pressure increase, and after so you can fill it back up to regular driving pressures). Helmets should be Snell SA rated, as DOT or Snell M rated isn't legal (unless it's a local club). Plus, sharing a helmet is kind of gross, even if you have a headsock (which you should get so you don't sweat into the helmet too much). Some clubs feed you, but if not, you can always go somewhere close with other AX'ers (and you should actively find people) so you can shoot the shit and learn as much as you can from seasoned drivers. Water should be available but brings lots (some frozen) just in case and stay very hydrated throughout. Lastly, good sun protection is a must. I wear sleeves and a wide-brimmed hat with sunglasses and sunscreen. Some more good advice: be sure to walk the course a few times, attend novice meeting, and get an instructor for at least half of your runs. Quote:
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I'm not sure what your experience level is but generally speaking (for those new), you should probably hold off on R comps. By throwing on R comps, you'll only be masking your mistakes and you won't learn as much as you would on street tires. Not only that, you'll be thrown into a different class with R comps and will face faster competition, so unless you're already modded to class spec, you're not doing yourself any favors and don't get me started on PAX index. Plus, the current batch of 200TW tires are very fast and it's plain embarrassing to be slower on R comps than those on street tires. |
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06-06-2018, 05:23 PM | #7 | ||
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I can't imagine 48psi! When mine get up to 40 it feels like I'm ice skating out there. Quote:
As far as tires go, The only reason I'm calling them done after 1500 is because of the outer tread. They would still be completely adequate for street tires as the inner, and main tread still look new. I think they would cord after a few runs at auto x though. Like you said, I'm looking more at 200 tread wears like re-71rs and star specs, not trofeo r's or r888. I should have clarified. I usually run right around the top of the pack. The auto-x isn't class based though, so they will not affect how I am grouped.
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06-07-2018, 09:21 AM | #9 |
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I still remember the first run of the first event about 8 yrs ago. I was soooo nerves and my heart was thumping like crazy at the start line.
After that first run, my hands were shaking. I will never forget that feeling. It's a lot of fun. |
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