My Autocross Thread
Yes. Even in comp mode, it kicks in traction control quite a bit on track. ESC off for me, but there seems to be some engine safety limit around 300% load, where it cuts back some power. I notice it at low RPM, high boost situations, like coming out of a slow corner, with the car loaded up in a turn.
For the bolt enlargement method to get camber, should I just open up the bolt holes 1/8" or so? Or should I put it on a mill and with the same diameter bit as the stock bolt hole bring the hole in towards the strut 1/8"?
a circular file works just fine. don't open it up past the outer larger diameter hole.
I'm going to try to make an interior mount for my shitty digital camera so I can start video taping my runs. But I think I lost alot of time in the two slalom sections because I was turning too wide. Is there any good way to "feel" where they are and where my sweet spot of speed and my line should be?
Lastly, my final run which didn't count for timing but I ended up running a personal best of 41.510! But anyways during that run I tried to focus on really stabbing the brake because I thought I was being way to conservative with them in other runs. But half way through the run I could feel the brakes getting a little soft and even shakking a little. The brakes have less than 1000 miles and felt fine driving home. Was this the fluid getting too hot? Should I look into DOT 4 fluid?
Hope some of that helped. Good luck out there.
Its fluid fade not brake fade.(pedal doesnt get soft during brake fade) Means its time for a brake fluid flush, and an upgrade in fluid. ATE Typ200/Superblue and Wilwood 570 are the most economical high performance fluids. Amsoil 600 is probably the highest performing for the money.
Did you mark the sidewall? Because if that's the case then you want to add a little more pressure up front to keep from rolling on the sidewall. The rears are fine. I usually run 42 lbs up front and 50 lbs in the rear. Gives me a little oversteer when I trailbrake into corners, and generally keeps the understeer to a minimum.
Your line through a slalom should be as tight and as fast as you can take the car without hitting a cone or losing control. Experience is the best teacher in this regard. If you aren't hitting a few cones during the day, you aren't pushing hard enough. It really takes practice and knocking a few of them over to get the hang of it.
Brake fade. I've been spoiled by the brembos on my car so I never have that problem. Somebody with some experience will have to help you with that.
Hope some of that helped. Good luck out there.
Your line through a slalom should be as tight and as fast as you can take the car without hitting a cone or losing control. Experience is the best teacher in this regard. If you aren't hitting a few cones during the day, you aren't pushing hard enough. It really takes practice and knocking a few of them over to get the hang of it.
Brake fade. I've been spoiled by the brembos on my car so I never have that problem. Somebody with some experience will have to help you with that.
Hope some of that helped. Good luck out there.
Also your saying to run more rear pressure than front? I thought less rear pressure caused move oversteer?
Its fluid fade not brake fade.(pedal doesnt get soft during brake fade) Means its time for a brake fluid flush, and an upgrade in fluid. ATE Typ200/Superblue and Wilwood 570 are the most economical high performance fluids. Amsoil 600 is probably the highest performing for the money.

Also your saying to run more rear pressure than front? I thought less rear pressure caused move oversteer?
I run with just enough air in the front to keep the tire from rolling on the side wall. In the rear I usually start with the pressure around 44 and then let it build up over the runs. Usually on my fastest run I'm running 42 up front and 50 in the rear. I forgot to add that 42/50 is my hot pressure (the pressure they get to after the tires have warmed up) My cold pressures are 42/44. Play with your tire pressures while your out there and see what you think helps you best.
I don't know how many miles you have on your Cobalt, how worn-out your CAB busnings are, but the fact that your tires shake under breaking would probably be corrected the the Powell CAB bushing set. I presently run the Powell Delrin bushing but I'm running a stock-type bushing instead of the Powell sphericals.
They work quite well, even with the very large slicks I run for autocross.
I've also drilled into my LCA over the front Delrin bushings (through the bushings into the steel shaft space), added a grease fitting, and I've started greasing the Delrin bushings -- stops the weird noises caused by rust on the steel shaft rubbing inside the Delrin.
Scott
They work quite well, even with the very large slicks I run for autocross.
I've also drilled into my LCA over the front Delrin bushings (through the bushings into the steel shaft space), added a grease fitting, and I've started greasing the Delrin bushings -- stops the weird noises caused by rust on the steel shaft rubbing inside the Delrin.
Scott
Also a couple of the honda guys there said a i needed "compliance bushings" I didn't know what that meant at first but they explained it as under hard braking my control arm trailing bushings are too weak and flexing causing the inside wheel to vibrate back and forth.
This is the spherical CAB the powell sells correct? Can anyone verify that is it what I would need?
This is the spherical CAB the powell sells correct? Can anyone verify that is it what I would need?
Good luck, looks like you are having lotsa fun out there!
yup happy to help out ; our stuff works and lasts a long time... my hXc front arms although pricey are the best of all worlds;stock appearing and full spherical front or rear, or you can go delrin leading /spherical rear for 400 dollars, add 260 and I can supply them installed in new arms... so 620 + shipping on a budget, 900 + shipping for the hXc package. Ask Matty O I just shipped a set to him.
Good luck, looks like you are having lotsa fun out there!
Good luck, looks like you are having lotsa fun out there!
Thanks John! It's a great time, I'm so addicted already. I would love to run your sphericals but due to class restrictions the bushings cannot be metallic. So knowing this what would you suggest I do? I thought that just getting the rubber replacements (Moog, Mevotech or Rebestos) without voids would help the play in the lca under hard braking but I could definitely be wrong.
Here is the rule for my class:
B. Suspension bushings may be replaced with bushings of any materials
(except metal) as long as they fit in the original location. Offset
bushings may be used. In a replacement bushing the amount
of metal relative to the amount of nonmetallic material may not be
increased. This does not authorize a change in type of bushing (for
example ball and socket replacing a cylindrical bushing), or use of
a bushing with an angled hole whose direction differs from that of
the original bushing. If the Stock bushing accommodated multi-axis
motion via compliance of the component material(s), the replacement
bushing may not be changed to accommodate such motion
via a change in bushing type, for example to a spherical bearing or
similar component involving internal moving parts. Pins or keys may
be used to prevent the rotation of alternate bushings, but may serve
no other purpose than that of retaining the bushing in the desired
position.
As Maven pointed out, I don't think I can run sphericals. I think they add to the amount of metal and change the type of bushing as the rule states. Is this correct according to the rule or could I run sphericals? I would love to I just don't want to break any rules even though no one would really know, I would just feel bad; same reason I swap my throttle body out every sunday haha
B. Suspension bushings may be replaced with bushings of any materials
(except metal) as long as they fit in the original location. Offset
bushings may be used. In a replacement bushing the amount
of metal relative to the amount of nonmetallic material may not be
increased. This does not authorize a change in type of bushing (for
example ball and socket replacing a cylindrical bushing), or use of
a bushing with an angled hole whose direction differs from that of
the original bushing. If the Stock bushing accommodated multi-axis
motion via compliance of the component material(s), the replacement
bushing may not be changed to accommodate such motion
via a change in bushing type, for example to a spherical bearing or
similar component involving internal moving parts. Pins or keys may
be used to prevent the rotation of alternate bushings, but may serve
no other purpose than that of retaining the bushing in the desired
position.
As Maven pointed out, I don't think I can run sphericals. I think they add to the amount of metal and change the type of bushing as the rule states. Is this correct according to the rule or could I run sphericals? I would love to I just don't want to break any rules even though no one would really know, I would just feel bad; same reason I swap my throttle body out every sunday haha
Qwiks rear spherical bushings are awesome, I ran the prototype ones on my last car for over 60,000 miles. They functioned like new still, no play. But they are definitely illegal in Stock/Tuning classes.
Thanks John! It's a great time, I'm so addicted already. I would love to run your sphericals but due to class restrictions the bushings cannot be metallic. So knowing this what would you suggest I do? I thought that just getting the rubber replacements (Moog, Mevotech or Rebestos) without voids would help the play in the lca under hard braking but I could definitely be wrong.
I'm also not recommending that.
It would probably blow your budget, and open up a whole lot of variables right while you're learning to get the most of your car.
Also, about tire pressures in autocross; there are some very good drivers who go lower in the rear to help rotation. I personally couldn't get the hang of it when I tried, but the theory is that the tire has a range that is its sweet spot. Being slightly over or slightly under those pressures reduces traction and helps rotate the car. My experience was that it was easier to go real high, and then drop them down until I found what worked for me. It was about 4 or 5 psi more in the rear than the front in a (different) car with a 57/43 weight distribution. If it's too loose in the rear, you won't do fast transitions well at all. You'll know it. Being just below that point was where I did my best.
I don't want to burst any bubbles, but the general ST rules state the following:
STX is for sedans/coupes with four seats and engines up to 5.1L normally aspirated
or up to 2.0L turbo/supercharged.
So you should be running in STX.
Scott
STX is for sedans/coupes with four seats and engines up to 5.1L normally aspirated
or up to 2.0L turbo/supercharged.
So you should be running in STX.
Scott
Well, you could always run in DSP (Do Spend, Please...). I think they're legal there...
I'm also not recommending that.
It would probably blow your budget, and open up a whole lot of variables right while you're learning to get the most of your car.
Also, about tire pressures in autocross; there are some very good drivers who go lower in the rear to help rotation. I personally couldn't get the hang of it when I tried, but the theory is that the tire has a range that is its sweet spot. Being slightly over or slightly under those pressures reduces traction and helps rotate the car. My experience was that it was easier to go real high, and then drop them down until I found what worked for me. It was about 4 or 5 psi more in the rear than the front in a (different) car with a 57/43 weight distribution. If it's too loose in the rear, you won't do fast transitions well at all. You'll know it. Being just below that point was where I did my best.
I'm also not recommending that.
It would probably blow your budget, and open up a whole lot of variables right while you're learning to get the most of your car.
Also, about tire pressures in autocross; there are some very good drivers who go lower in the rear to help rotation. I personally couldn't get the hang of it when I tried, but the theory is that the tire has a range that is its sweet spot. Being slightly over or slightly under those pressures reduces traction and helps rotate the car. My experience was that it was easier to go real high, and then drop them down until I found what worked for me. It was about 4 or 5 psi more in the rear than the front in a (different) car with a 57/43 weight distribution. If it's too loose in the rear, you won't do fast transitions well at all. You'll know it. Being just below that point was where I did my best.
Thanks for your experience, I think I'll try 43 in front and 47 in back this weekend. See how that goes and work from there.
I have the LE5, thanks for your concern though.
Wang thanks a lot for that link. The AMT camera mount came yesterday, I already love it. Its quality is amazing and fits just about any car. Well the event is tomorrow in Syracuse so I'll post up pics/in car vids tomorrow night!
Thanks John! It's a great time, I'm so addicted already. I would love to run your sphericals but due to class restrictions the bushings cannot be metallic. So knowing this what would you suggest I do? I thought that just getting the rubber replacements (Moog, Mevotech or Rebestos) without voids would help the play in the lca under hard braking but I could definitely be wrong.
Well today went very well! I finished 2nd in novice class and 19th overall out of 45 drivers. The course was pretty difficult but I can already feel myself getting better. There were two major decreasing radius turns, and I actually got one of them down pretty well. One problem I was having though was with my line. I picked out what I thought was a very good line for an understeering car and even the novice chair agreed with me, late apexes on the decreasing turns and tight around slower obstacles. However once I actually started driving I was having a lot of trouble sticking that line. Not sure if that will just come with practice of if I'm doing something wrong.
Here's a vid of my best run, you can't really see the course much but any advice is more than welcome!
Cobalt CNY SCCA Solo Run7.AVI - YouTube
edit: Too tired tonight to post all the pics, I will tomorrow.
Last edited by noorj; Jun 10, 2012 at 11:38 PM.
You sure are doing better. In my opinion, you need to look at how you hold the wheel; looks like you got happy hands, and its hard to get the car settled right that way. Think about how you turn in; do you push with the left hand to turn right, or pull with the right? Pushing is better.
9/3 is best as a default position.
good work!
9/3 is best as a default position.
good work!
You sure are doing better. In my opinion, you need to look at how you hold the wheel; looks like you got happy hands, and its hard to get the car settled right that way. Think about how you turn in; do you push with the left hand to turn right, or pull with the right? Pushing is better.
9/3 is best as a default position.
good work!
9/3 is best as a default position.
good work!
What do you mean by happy hands? Like too much movement? And I honestly am not sure but I think I pull, I'll try pushing next time!
pictarz
By the way, I ran 45psi up front and 42 rear. Seemed like a good amount of rotation, hot pressure measured 47f 43rear
Here's the ones of my car first. Girlfriend took a lot, tried to pick out good ones. She is getting better though haha













By the way, I ran 45psi up front and 42 rear. Seemed like a good amount of rotation, hot pressure measured 47f 43rear
Here's the ones of my car first. Girlfriend took a lot, tried to pick out good ones. She is getting better though haha























