width of a chicago box
 

I've got my first head designer duties for our local pca autocross this weekend. I'm planning to incorporate a Chicago box. It needs to be fairly slow, as it is the last element before the course goes between some curbs. What's the typical width between the three "slalom" cones in a Chicago box?


The approach will be directly following a turn that will bring cars in at approximately a 45' angle. The exit will have the cars continuing straight in line with the 3 cones.

Thanks for your help.

Not big enough? :)

I want to say the ones I encountered last weekend were quite similar (equal?) to minimum slalom spacing, but I didn't think to compare it to a slalom because, well.... the approach was, at best, about what you describe and only if you got the line just right. :) I'm really not the person to ask though, I only stopped having the usual stupid settle over me the 2nd half of the 2nd day (though there was only one on day 2)

the minimum distance between the cones in a slalom (Chicago Box) is 45 feet
per SCCA rules.

i would keep the distance between 45 & 50'.

From one of the best in our local area, this may be useful for you:


http://detroit-scca.org/e107/e107_fi...e_designer.pdf

If you're at the Bowie lot and using the bottom section, I would be most concerned with making sure the cars are going straight through the curbs and preferably less than 15mph on entry. It sucks, but it's the safest bet at that lot in order to avoid paperwork.

Yes, Bowie. The curbs suck, as well as all the bad pavement on the bottom section. I've drawn a Chicago box using the extra room to the left at the bottom of the top section, then through the curbs.


Dunno, but 15mph seems a bit extreme. Don't think we've ever slowed cars that much. My theory has always been going through straight is more important than slow.

The origin of the Chicago box: http://www.team.net/archive/autox/2005-12/msg00047.html

Of course, the rules were amended to treat "features like slaloms" as slaloms and subject them to the minimum slalom distance rule. So if your Chicago box drives like a slalom, 45 feet. If your Chicago box drives like a pivot turn, then gate it wide enough for cars to fit.

Fun info. I'll start with 45-50 feet (20 paces) and add as necessary.