sevenspeedracebarge blog kind of thread

Discussion in 'General Chat' started by sixspeedfirebird, Aug 23, 2015.

  1. My feeling is similar, but I don't have a radar detector or a dash cam, so I guess I'll just go for a drive

    srs though I want to get a gopro or something and film some roads near me. There good.
     
  2. Going autocrossing again tomorrow to finish killing of my rear tires.

    962, what kind of tire pressures would you recommend? 40/40 cold?
     
  3. So Rick Ross can drive

    Even with that over shoulder look my brain still can't make the cones make sense
     
  4. My exact feeling

    give me highlighted route with blue, yellow and red disappearing marks so I know what the **** to do
     
  5. sorry dude didn't see the post in time but 40/40 sounds like a good start. if you have a tire with stiff sidewalls that should be plenty, but if the sidewalls are soft and roll you may need more pressure. i tend to go a couple psi higher in the front usually. if you get the chance mount the gopro once on the side of the car so that you can see the tire sidewall under hard cornering, it's pretty cool seeing it actually.

    however, if you really want to do it right the correct way is by reading accurate temps on the inner, middle and outer section of the tread and setting tire pressure accordingly (camber would also matter i assume).

    the crude way is to go high enough to prevent sidewall rollover, unless the sidewall is so soft it needs redonculous pressure in which case you have to compromise.

    From 'www.cjtire.com'
    "Due to modern tire constructions, the chalking of the tire shoulder to determine proper inflation pressures for track and autocross by looking at tire rollover is no longer accurate. The only truly accurate way to determine the optimum inflation pressure is to take trade temperatures with a pyrometer. The goal is to obtain even tread temperatures across the tread surface (inside shoulder/center/outside shoulder). The temperatures should be taken immediately after coming off the track.

    On street cars, you will probably not be able to obtain an even tire temperature distribution due to the suspension geometry. In this case, try to get a linear temperature distribution such as
    225/200/175 degrees outside/center/inside temperature spread. A hotter outside and cool center and inside mean you need to increase pressure. A hotter center temperature needs lower pressure. Add or subtract pressure in 2-3 psi increments."
     
  6. btw if you are going to need new tires and you autox the car sometimes it would be a good idea to go with some good extreme performance summer tires if that's in the budget
     
  7. If I'm going to continue autocrossing (and hopefully a couple full track days/weekends) I think I'll get a separate set of fun tires for my 18"s that I run snow tires on.
     
  8. I ended up 22nd out of 31 overall yesterday, got 8 runs total, 37.0 > 36.3 > 36.3 > 35.4 *morning break* 36.8 > 36.2 > 36.0 > 36.1

    I'm pretty happy with the consistency, but that 35.4 tells me the car had some more to give, just not sure what I really got right that time vs all the low 36 runs.

    [​IMG]

    About the cars, pretty much all of the Miatas are on sticky tires and have had significant suspension work done.

    The 5th place GTR got faster and faster throughout the day. Like my car, you could tell it would've been much happier doing some high speed work.

    6th place S4 and the 3rd gen Firebird in 7th were setup extremely well.

    The '78ish Mustang II that came in 15th was scary as hell to watch. Car had a ton of power, had all of the weight stripped out of it, but didn't seem like it handled particularly well. I was working the hardest braking zone of the course, and everytime the Mustang came at me I pee'd myself a little.

    The MR2 in 17th was the same car as the one that finished 31st. Shows the difference in an experienced driver vs someone new he brought along this time.

    The 325i in 21st is an LS1 swapped '91 E30 coupe making somewhere around 400whp. Was the driver's first attempt at an autocross, but that car should be scary quick if he sticks to it. Unfortunately he snapped an axle on his last run of the day.

    The 2015 Z28 in 23rd was a new driver as well, and his first run was terrifying as a corner worker. He elected to not have anyone ride with him for his first run, and he was simply all over the place. He didn't really learn the course before hand at all, so he was trying to maneuver 100% on the fly, in a 500hp Camaro. He was off course three times during his first run, and nearly took out two sets of corner workers, including myself.

    And this was the GTR that finished in 24th, uuuunnnngggghhhhh.

    [​IMG]
     
  9. those are very consistent runs. if you are planning on getting tires specifically for autox, they will be different from something more track oriented as they need to grip without much heat. such tires tend to overheat after a few hard laps on the track. the best compromise i can think of are hankook rs3 v2's. there are a lot of other options, direzza zII star spec, potenza re71r etc but the hankook is the best all around which tends to handle heat and tracking better than the other two. what rim width are the 18's? if you can run more tire, particularly on the front it would be really beneficial, specially for auto-x.
     
  10. Another monthly autocross done, really really tough course for my big ol car this time out. Ended up 24th out of 27. Course was extremely tight and the 180* was almost too tight for me to turn through. Ok not really but I was definitely struggling.

    Videos here http://tinyurl.com/AutoXM5 , including a helmet cam view that I thought was pretty fun, and some videos with a rear bumper mounted microphone for moar V10 noises.
     
  11. bumper mic rules
     
    sixspeedfirebird likes this.
  12. Car randomly decided not to start today. Possibly the starter, more likely a loose positive connection somewhere. Dammit.
     
  13. sorry to hear, but bound to happen!
     
  14. Starter died, repair bill .... $2392. LOLOLOL.

    Extended warranty covering about 80% of the bill, so not so terrible. Starter is $720 for new BMW part, and quoted FOURTEEN HOURS for labor. Apparently everything that sits in the V of the engine has to come out to access the starter, and the driveshaft has to come out to remove the final bolts. Absolutely insane considering I changed the starter out on my old pickup in my driveway in about 30-45 minutes a couple years ago.
     
  15. Sounds like you should ditch that thing when warranty is up.
     
    sixspeedfirebird likes this.
  16. Now they're saying the starter was fine and the CAS module is the problem. Stereotypical electrical problems where the dealership is just replacing stuff as they go. Of course each part has to be VIN recoded, so it's going to be at least another week. At least the warranty company isn't fighting me too hard. They did argue that the CAS module wouldn't be covered, because my warranty only covers the "engine control module and its related systems", but BMW's description of the CAS is "an integral part of the ECM", so don't think their argument will stand.

    Asssssssssssssssssssssssssssssssssssssssssssssssssssssssss.
     
  17. this is the part where my fear of cool used european cars is justified and I resign myself to practical transportation appliances
     
    ETB4U and sixspeedfirebird like this.
  18. CAS unit being paired to the car now, should be good to pick it up this afternoon. About time too, damn tired of this old Chevy Lumina ( @MooSquad style ) I've been driving the last two weeks.
     
  19. Hm, Lumina? Are we talking old-awesome Lumina or that post 1996'ish thing?
     
  20. Ahh, its a 2001, couldn't quite remember your cutoff point.
     
    MooSquad likes this.
  21. Hopefully you're car will be back in working order shortly. On the bright side, going from a Lumina back to the M5 will be like going on a second Honeymoon!
     
    sixspeedfirebird likes this.
  22. oh God a Lumina
    will this nightmare never end
     
  23. No it will not! Got trolled, CAS module didn't fix it. Dealership basically saying "lol idk" now, going through the wiring harness again. Did confirm I wouldn't have to pay for the other stuff since it didn't do anything.

    So, ya know... yay for free new starter and CAS module?
     

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