Race Prep Miata race-only chat.
Sponsored by:
Sponsored by:

Some Autox Discussion

Old 04-12-2010, 11:33 AM
  #1  
Elite Member
Thread Starter
iTrader: (8)
 
wayne_curr's Avatar
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,712
Total Cats: 4
Default Some Autox Discussion

Had a great weekend with my local car club at our autocross season opening. We held a school on saturday and event #1 yesterday. Was a great couple of days. Being so involved in the club earned me the right to stay after the school yesterday afternoon with a bunch of other friends/club members and just play on the course for the rest of the afternoon. We all played on the skid pad till we were dizzy and did the slaloms over and over again. We drove each other's cars and it was an absolute blast. Hopefully someone grabbed some pics!

Anyway, I learned a lot about my car's setup.

First of all, the KYB AGX's, while they suck badly, aren't really slowing me down at all. There was a huge lump in the middle of an off camber, downhill right turn that would upset cars horribley and put their dampers to the test and I was reasonably pleased with how my car took it versus the guy with the Fatcat revalved bilsteins. I really expected more from those to be honest.

Second, all you newbs need to put your rear sway bars on. I dont know how you stand it, or how I stood it for so long for that matter. I spent a LONG time playing on the skid pad trying to understand the dynamics of my car and without the sway bar I just could not induce any kind of oversteer no matter how hard I tried. I had my friend yank the e-brake and still nothing, no spin, no sliding. The understeer was so bad that it was seriously limiting my speed around the circle. I ran home and put my rear sway back on and OMG. It allowed me to go MUCH faster around the circle since it allowed me to actually throttle steer around it. The car actually rotates now and in a much more controllable way. I understand so much more now than I could possibly explain.

Third, Launch control. While I didn't use it much at the event on sunday due to its uselessness with the course design, we had a timed ~60ft launch setup at the school on saturday. Without launch control I was getting solid 2 second times and Jacki was getting solid ~2.125 second launches. Jacki's first time with launch control she got a 1.8** and so did I. After that, every single launch was in the 1.8s reliably after 15-20 more launches. If I had my laptop and could play with the settings I think we could have gotten the launch down to 1.6. While she didn't understand the fun in this, I thought it was kind of a fun game getting the same consistent launch times while everyone else tried to catch up. The WRX beat us with a 1.6**.

My biggest issue of the day was the tight slalom. My little 5'2" girlfriend had an even harder time muscling my non-power steering car around. Stock miatas with power steering where 2+ seconds faster than us (one of them on snow tires) through the course. Now, i will admit that the drivers need more work for sure, we're slow drivers, but I think a lot of it has to do with power steering, or atleast the power steering ratio. I drove a 92 stock on the course and could not believe how quickly you can toss it around cones with the better steering ratio.

I dont know where I actually stood in my class but i'm hoping not last. I probably did get last though. I got all clean runs except my last one with a big smokey spin in the skid pad. FTD went to a turbo civic on R888s, second fastest to a Volvo 240 on street tires, third to an STI on street tires. The Volvo gets mad respect, but the FWD cars (after getting a chance to drive a couple of them through the course) just make it so easy especially on R-comps. Very idiot proof.
wayne_curr is offline  
Old 04-12-2010, 12:29 PM
  #2  
Elite Member
 
Sparetire's Avatar
 
Join Date: Dec 2008
Location: Colorado
Posts: 1,642
Total Cats: 36
Default

Possibly one of the best posts I have read in a awhile, thanks for all the info!

One question:

From what I am reading, you have an actual manual rack, as opposed to a de-powered rack?
Sparetire is offline  
Old 04-12-2010, 12:31 PM
  #3  
Elite Member
Thread Starter
iTrader: (8)
 
wayne_curr's Avatar
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,712
Total Cats: 4
Default

Originally Posted by Sparetire
Possibly one of the best posts I have read in a awhile, thanks for all the info!

One question:

From what I am reading, you have an actual manual rack, as opposed to a de-powered rack?
Yes, I have a standard manual rack.

I just bid on a power rack on ebay and sent a message off to lev to see what they run. This plus a front sway is probably all I will upgrade this season as I just want to improve on my driving and start getting good at playing with tire pressures.
wayne_curr is offline  
Old 04-12-2010, 12:37 PM
  #4  
Elite Member
iTrader: (7)
 
mgeoffriau's Avatar
 
Join Date: Jul 2009
Location: Jackson, MS
Posts: 7,388
Total Cats: 474
Default

How the hell did the Volvo set the 2nd FTD?
mgeoffriau is offline  
Old 04-12-2010, 12:55 PM
  #5  
Elite Member
Thread Starter
iTrader: (8)
 
wayne_curr's Avatar
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,712
Total Cats: 4
Default

Originally Posted by mgeoffriau
How the hell did the Volvo set the 2nd FTD?
Great driver and a pretty well built car. There was another volvo but it was a wagon and he was pretty quick too but his car had Just been put on the ground the night before after a long winter build. He would have been faster if he wasn't actually tuning while doing runs.
wayne_curr is offline  
Old 04-12-2010, 02:28 PM
  #6  
Junior Member
iTrader: (2)
 
mikewolf's Avatar
 
Join Date: Oct 2007
Location: Near buffalo
Posts: 140
Total Cats: 0
Default

I can't understand why your car won't oversteer. My STS car will still oversteer easily with a big front bar and no rear bar. Even with hoosiers (obviously not in STS at the time)
mikewolf is offline  
Old 04-12-2010, 02:31 PM
  #7  
Elite Member
Thread Starter
iTrader: (8)
 
wayne_curr's Avatar
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,712
Total Cats: 4
Default

Originally Posted by mikewolf
I can't understand why your car won't oversteer. My STS car will still oversteer easily with a big front bar and no rear bar. Even with hoosiers (obviously not in STS at the time)
Perhaps its alignment. My car hasn't had one yet this year and is 20 years overdue for new eccentrics. But I swear that no matter how hard we tried we couldn't get it to oversteer, it felt worse than a FWD car on the skid pad.
wayne_curr is offline  
Old 04-12-2010, 03:16 PM
  #8  
Elite Member
iTrader: (8)
 
webby459's Avatar
 
Join Date: Jun 2009
Location: Albany, NY
Posts: 1,461
Total Cats: 4
Default

I don't doubt that your car pushed on the skidpad without the rear bar. Fortunately, though, autocross is about more than just the skidpad. Where not having a rear bar helps most is in power application. This also happens to be the strong point in our cars, so it needs to be exploited in any way possible. Removing the rear bar is the most widely accepted way. Just like everything, there is a give and take.
webby459 is offline  
Old 04-12-2010, 05:18 PM
  #9  
Elite Member
Thread Starter
iTrader: (8)
 
wayne_curr's Avatar
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,712
Total Cats: 4
Default

Originally Posted by webby459
I don't doubt that your car pushed on the skidpad without the rear bar. Fortunately, though, autocross is about more than just the skidpad. Where not having a rear bar helps most is in power application. This also happens to be the strong point in our cars, so it needs to be exploited in any way possible. Removing the rear bar is the most widely accepted way. Just like everything, there is a give and take.
Good way to put it. I found, personally, I was faster through slaloms with the rear bar because I could throttle steer it and rotate around the cones in a way that just didn't happen without the rear bar.
wayne_curr is offline  
Old 04-12-2010, 10:00 PM
  #10  
Elite Member
iTrader: (3)
 
Pitlab77's Avatar
 
Join Date: Dec 2004
Location: Houston
Posts: 2,914
Total Cats: 5
Default

I concur on the agx. My car trophied in C-stock with 2 owners, 3 drivers in many different areas of texas.

Although they are truly pos but they can get you buy. I love my new set up. CG + revalved bilsteins

Yes no bar will remove over steer. Can be use to cure some problems on some cars though.

3. My car is non power anything NB. Me and my co driver practically always faster than the PS cars. Just have to react quicker and before you have even crossed a cone.
Pitlab77 is offline  
Old 04-12-2010, 10:21 PM
  #11  
Junior Member
iTrader: (3)
 
alik's Avatar
 
Join Date: Nov 2007
Location: Boston / '90 Mariner Blue
Posts: 330
Total Cats: 14
Default

I run no rear bar, and can induce oversteer at will. This is with less than stock hp. (1.6L & 4.1 diff).
alik is offline  
Old 04-13-2010, 01:32 AM
  #12  
Elite Member
Thread Starter
iTrader: (8)
 
wayne_curr's Avatar
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,712
Total Cats: 4
Default

Originally Posted by alik
I run no rear bar, and can induce oversteer at will. This is with less than stock hp. (1.6L & 4.1 diff).
You must be running more spring than me then. I'm on FM springs.
wayne_curr is offline  
Old 04-13-2010, 06:43 AM
  #13  
Junior Member
iTrader: (3)
 
alik's Avatar
 
Join Date: Nov 2007
Location: Boston / '90 Mariner Blue
Posts: 330
Total Cats: 14
Default

I used to run on FM.
alik is offline  
Old 04-13-2010, 01:53 PM
  #14  
Elite Member
Thread Starter
iTrader: (8)
 
wayne_curr's Avatar
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,712
Total Cats: 4
Default

Results are up.

My class.
http://scorekeeper.wwscc.org/results...yclass?list=C7

Girlfriend's class.
http://scorekeeper.wwscc.org/results...yclass?list=C6

Overall list of scratch times. I was wrong about the volvo although they were still fast.
http://scorekeeper.wwscc.org/results/cscc2010/1/topraw

I think we are going to race the rest of the season in our Integra instead of the miata. We'll have a much better Pax.
wayne_curr is offline  
Old 04-13-2010, 03:11 PM
  #15  
Moderator
iTrader: (12)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 20,645
Total Cats: 3,009
Default

Perhaps the need or lack of need for a rear bar is tied to the front vs. rear spring rates each of you is running. My RX7 was very well balanced on stock springs with FM front and rear bars. In a steady-state turn you could just add or remove throttle to change from under to oversteer. It was dead predictable and easily controllable at the limit. The next owner added very tight springs to the car and it would corner well up to a point, then snap oversteer violently. I have no spring rate data.
sixshooter is offline  
Old 04-14-2010, 07:35 PM
  #16  
Elite Member
iTrader: (3)
 
Pitlab77's Avatar
 
Join Date: Dec 2004
Location: Houston
Posts: 2,914
Total Cats: 5
Default

Well I am telling you what my experiences was. I do not mean understeer.
Pitlab77 is offline  
Old 04-16-2010, 07:41 PM
  #17  
Elite Member
iTrader: (7)
 
flier129's Avatar
 
Join Date: Jan 2008
Location: Statesville, NC
Posts: 2,737
Total Cats: 317
Default

Has anyone ran koni race's at an autox event? If so what springrate did you run, swaybar(s), what type of diff, and how much powah?

Pondering on a new suspension setup, wondering if 750/450, f/r , will be too much and if the koni race's would have anything over the standard yellow.
flier129 is offline  
Old 04-16-2010, 08:04 PM
  #18  
Junior Member
iTrader: (2)
 
mikewolf's Avatar
 
Join Date: Oct 2007
Location: Near buffalo
Posts: 140
Total Cats: 0
Default

Originally Posted by flier129
Has anyone ran koni race's at an autox event? If so what springrate did you run, swaybar(s), what type of diff, and how much powah?

Pondering on a new suspension setup, wondering if 750/450, f/r , will be too much and if the koni race's would have anything over the standard yellow.
Koni Race's work well with those spring rates. That's a common setup for STS and even some CSP guys.
mikewolf is offline  
Old 04-17-2010, 08:18 PM
  #19  
Junior Member
 
sixace's Avatar
 
Join Date: Jan 2008
Location: Gainesville, Tx
Posts: 227
Total Cats: 1
Default

Originally Posted by flier129
Has anyone ran koni race's at an autox event? If so what springrate did you run, swaybar(s), what type of diff, and how much powah?

Pondering on a new suspension setup, wondering if 750/450, f/r , will be too much and if the koni race's would have anything over the standard yellow.
I have that exact combination on my "90. Works very well. Using the big, hollow RB bar up front, stock bar in back. The RACE shocks are valved to handle the spring rates and are 1" shorter. The yellows are supposed to be pushing it/done at 500# rates.

If it's a DD, it's not real comfortable depending on how the roads are. Very stiff (catching air over train tracks is fun though). The setup handles both autox and track days very well.
SA

edit: actually my combo is 700/450...
sixace is offline  
Old 04-17-2010, 09:53 PM
  #20  
Elite Member
iTrader: (13)
 
falcon's Avatar
 
Join Date: Dec 2009
Posts: 2,499
Total Cats: 16
Default

Originally Posted by wayne_curr
Yes, I have a standard manual rack.

I just bid on a power rack on ebay and sent a message off to lev to see what they run. This plus a front sway is probably all I will upgrade this season as I just want to improve on my driving and start getting good at playing with tire pressures.
I'll trade you racks?

I was going to de-power mine. How different is the ratio between the power and manual racks?


Where do you AutoX? You should come up to Pitt Meadows sometime and run up here. I wouldn't mind going south for an event or two.
falcon is offline  

Thread Tools
Search this Thread
Quick Reply: Some Autox Discussion



All times are GMT -4. The time now is 12:21 PM.