Autocross Car Handling Quirks

Here’s more about my first autocross & discovering some handling quirks of my 2000 Nissan Maxima SE (at the 10-19-2008 SASCA autocross).  After this event, I call my car the ‘Big White Whale’.

One of my initial concerns was that my car is in the same class (G Stock) as cars such as VW Golf GTIs.  That didn’t seem fair to me.  But upon reviewing the video that Brian took of my runs, I found an amusing common autocross handling issue with both of our vehicles.

They will both lift their rear inside tire upon severe cornering input.  This is an action shot of Paalo at speed in his VW Golf GTI, at the SPOKES autocross on 10/5/2008.  Look closely (or click to enlarge), you can see that inside right rear tire lifting up.

Installing a front anti-roll bar would greatly reduce the major tendency for my car to plow (aka: understeer) through the corners.  For now, I think I’ll save my money.  Anyway. see for yourself how my car “danced” through this course with 97K miles plus on the clock.

The 3-legged corner stance - version B

These are screenshots of moving video – excuse the lack of detail, but you can see what I mean.  Here’s a better shot (with all 4 tires on the ground)!

For those of you who’ve been waiting, here’s my first run video on YouTube:

I will post more about the learning progress, how I made my way through my first autocross of this century.  Racing Ready was there to document this for you!

Dan

Proper Racing Line in Autocross

Looking at an autocross layout map, even walking a course can only somewhat familiarize yourself with a new course.  Running the course at speed is a “whole ‘nother kettle of fish”.

Take the case in point of the last SASCA autocross of 10/19/2008.  I can relate to this event more any of the previous autocross events that I’ve attended this year.  This was where I lost my autocross “virginity” after 15 years.

Below is the original, unmarked course layout map.  This is the “before” version.

Before...
Before...

Below is the revised, course layout map I had marked up/edited.  This is the “after” version.  Click on the image to see better detail of my drawn line versus the cone locations.

After !
After !

You may beg to differ on my sketching of the layout – that’s fine.  I’m new at this.  This is what I felt was close to the best line for my front wheel drive car, on that 1st day for me.  Competitors of different cars & experience levels would probably define a more educated, different path.  Whatever…

Let me illustrate how driving through a specific corner a number of times helps to better find the proper line on corner #2.  This happened to be the same corner I had done corner worker duty (details here).  While watching many drivers go through that corner, we were better able to see what would be a better line than we thought initially.

Here is an illustration of an initial “bad” racing line (red line w/purple arrow) & an “experienced” racing line green line w/ blue arrow) for corner #2.  Doing what “Mr. Green Racer” did, swing wide before that final cone in the left-handed sweeper, set him up better for that right pointing cone that many competitors hit in the first heat, and hardly at all in the second heat.

My point here is that these lines aren’t so easy to see until after driving them a number of times.  Thankfully, we had eight runs to try to get it right.  I improved only slightly, but the key is, I did improve!  More about my full-on experience on another day…

Racing Ready is willing to learn more…

Dan

Autocross Tire Pressure Notes

wheelspecs.com window sticker
wheelspecs.com window sticker

Paalo, of Golf GTI DSG (Direct Shift Gearbox) fame (and purveyor of wheel specifications fame at wheelpecs.com), had sent me the following, to give me some pointers for preparing for my first participatory autocross, on 10/19/2008.

Golf GTI on grid waiting for Paalo
Golf GTI on grid waiting for Paalo

Start at 45 front and 50 rear.  Be sure to re-check them before runs.  If you can get some clean runs in, but still feel like you want a little more precision from the car, bump them up another 5.  The trick is getting in some runs you feel at least slightly happy with before you start trying to change things.  If they start feeling really slippery, they’re getting greasy and you’ll need to start spraying them to cool the tires, but it’s not something I’d worry about your first time out – just want to make sure you know there’s a difference between slippery due to greasiness and wonky handling due to pressures.  It’s already getting cooler so greasiness shouldn’t be much of a factor although your compound does get harder with age ……..  Just have to drive em’ and see.

Paalo at speed
Paalo at speed

Thanks to the useful resources of SASCA (a source of compressed air to increase tire pressures), I went back & forth with tire pressures between 50 PSI to 42 PSI.  Having 8 runs to get my car sorted out got me a chance to learn how my car reacts with different pressures front & rear…

I had planned to post more information about my first autocross run specifics, but I haven’t yet been able to get the screen shot images to save correctly.  I’m working on this as I want to show you something fun, something my car has in common with the VW Golf!

Racing Ready is working to show you more…

Dan

Racing Ready Blog Maturation Process

Obviously I enjoy most aspects of the motorsports scene.  It’s why I write this blog.

Motorsports

But I want to take this blog beyond the “hobbyist” level.  I’m trying to make the look & feel more professional, and I’ve to moved onto a third theme.  This theme is of the 3-column variety, and it gives me more flexibility to be creative.  You will be able to navigate the site more intuitively and you will be able to view & interact with other content and ads more professionally.

Again, as most of you know, this IS a work in progress – please be patient.  Besides the look and feel, I am slowly working on building site visitor traffic.  I REALLY appreciate your time spent reading my thoughts, observations and enjoying the photos.  I DO ask one favor – please let your friends know about this blog.  They can subscribe to my RSS Feed.

Racing Ready thanks you for your readership & I look forward to any comments, suggestions or even rants that you may offer.

Dan

Better Breathing Corvette Z06

One of the benefits of doing corner worker duty, that I failed to mention here yesterday, is that you can get to know your co-competitors better.  One of my corner co-workers, Eric, brought his car to the 10/19/2008 SASCA autocross.  It’s a screamin’ yellow Corvette Z06.

On grid, between runs
On grid, between runs

It’s relatively street stock.  Most of the modifications I could see were aesthetic in value, but it sure looked faster.  Being that it’s in the ASP (A Stock Prepared) class, there is more that Eric didn’t tell me.  On the performance side, he did say he made a major effective performance upgrade by adding a K&N cold air intake & filter.  Eric thinks it has added at least 10HP, if not more.

Business end view, while on grid
Business end view, while on grid

I know that as a present and past user of K&N filters, this accessory is the most cost effective accessory you can put on your car or truck.  It is just a simple air cleaner swap, fitting in place just like your standard, factory air cleaner.  The guys at K&N seem to know what they’re doing, as the car just breathes better, runs smoother & it accelerates more strongly, like it has additional torque.

Z06 engine bay detail - the K&N Filter is to the left
Z06 engine bay detail - the K&N Filter is to the left

I feel so strongly about K&N filters, that I firmly believe this should be your FIRST performance upgrade to your car or truck!  To assist you in this, I will be putting up a new ad on the page this weekend – you’ll see it when I change over to my new WordPress blog theme.  Tomorrow, I hope.  In the meantime – ENJOY!

Racing Ready is on the move!

Dan