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For those who don't know who Byron Short is or have his formula,  it can be found by googling Byron Short Slalom formula to be:

 time between cones = (pi / 8) * sqrt( d / g)

where d is the total offset side to side (carwidth + conewidth + 2 x cone clearance difference);  g is in gees representing the amount of turning capability a car has. 

 from:

http://forums.bimmerforums.com/forum/archive/index.php/t-264985.html

I don't know the assumptions, for instance:  Does it use a constant gee loading on the car body or does the gee loading vary sinusoidally.  My datalogger indicates that tire load seems to vary somewhat sinusoidally between cones for instance.  One can imagine a very complicated model that includes time delays between changing steering wheel directiosn and even possibly wheel reaction forces hysterisis.  I suspect that the Byron Short model is based on either a constant gee loading to turn through the cone or at most a sinusoidal gee loading through the turn.  Note that the units in the equation don't make a whole lot of sense so I'm guessing that there are a bunch of factors that cancel out to get to the equation as written.

TeamRX8:

The grip level at Grissom surely played into it.  It would be interesting to see the difference by setting up the identical element at Heartland Park  ...  oy vey!

Would be fun as long as Andy stays away from power posts....

MaxQ shows me entering the slalom at 62.4 mph and exiting at 61.3. I have my rev limitered turn down a bit right now and did pop it a few times going thru the slalom.

Dan

harts:

their was no offset at all , they were all lined up straight unless someone moved them after i layed them out,, for me i don't think this thing drives much like what a regular  slalom does  with the 55 ft gap it seems like it would be slow but then you got 40 feet to gather the car back up before the next 55ft gap,  this is a very interesting feature that i have not seen before and was a lot of fun, and something different that was not  painfull to drive ,, all the measurements were from center line to center line of each cone and were with an inch of each other

This explains the course dependency theory/conspriacy thing too  Mr. Harts.  Hence why you and Wes were right in the meat of your gear vs David, Jack and I.

Plenty of people will verify that my Civic was HAMMERING on the rev limiter from the end of the very first wall of cones (58mph actual) on my first and third runs.  My co-driver short shifted into third at 54 and held his foot to the floor on all three of his runs and I did on my second run.  When I looked at my speedo at the end of the slalom on my second run to verify speed, I was showing 66mph which is 3.4 mph fast with my tire sizing to really see if the shift was worth it.  I personally never lifted through that section on any of my three runs regarless of speed.  Had I have started that section slower, I wouldn't have hit the limiter and had the surface been asphalt...no way would I have been able to hold it.

As an up & coming course designer, I am learning that such elements are kick-ass fun...as long as they are safe. 

Windscreen:

Actually, I'm starting to feel better about my slalom speed in the Queen Mary based on the reported speeds here.  I'm also starting to see the light in how the walls (leading cones) force a wider, slower line.  In the slalom formula I have to plug in an offset of 34" to bring the speeds down to those observed, so it is like the center cone in each wall is moved 17" toward the outside.

Anyway, Traqmate data logs shows my max speed into and out of the wallom at 65mph.  Minimum speed in the middle of the wallom was 56mph.  Even my 3rd run in the damp was the same speed, so it was just like it felt -- decent grip on the way out, only the turn around to the finish was too wet to go any faster on my 3rd Sunday run.

FWIW, I don't think the Elise slaloms all that well with the rear engine.  I think the C-Stock 1999 Miata I ran years ago slalomed better than the Elise.  The Elise excels at fast offsets that are much more than a slalom.

Matthew.

matthewb:

FWIW, I don't think the Elise slaloms all that well with the rear engine.  I think the C-Stock 1999 Miata I ran years ago slalomed better than the Elise.  The Elise excels at fast offsets that are much more than a slalom.

Matthew.

You drove that Elise well past it's limits.  It looked very loose with a good amount of body roll in many sections. I was working corner 5 radio on day 2 when you were running.  When you came through, the Elise was waayyy out of shape and somehow you did a great job of handling it but still got the aggressiveness award for heat 3!  You were going through the walloms much faster than anyone else but kept getting out of shape towards the end of it. Had you backed off one inch, I think you would have made it though without getting that out of shape.  BTW it was nice meeting you! Best of luck for the rest of the season.

-Marc