Chatter about chatter

Does your car chatter?

This has been a reoccurring theme lately.  The introduction of the Pit Shimizu and Tamiya "TCS" tires has been a good thing, but it's a lot different from foam tire racing, or even the older style Tamiya tires.

Many of the racers I talk to are concerned about their cars chatter/hopping.  I get a little upset to see it myself.  Typically, a car that chatters in the corners is having some sort of problem.  Pan cars that chatter are worrisome for sure, but consider that we are in a situation which is not typical of pan cars.  These cars now run heavy rubber tires, with a tremendous amount of grip.  They are also narrow.  Now add in a surface like carpet, and you're definitely looking at some hop.  These cars are not smoothly getting into a drift angle like foam tire shod cars do.  Everybody seems to want to cure this immediately since it's so disturbing.

Maybe it's a lot of worry about nothing.

I was thinking back to the 2010 TCS North American Finals.  Danny Hua won the class and the trip to Japan, and I remember quite vividly seeing his car chatter the front end on the left side of the track.  Like a lot of people who see this stuff now, I thought "Wow, his car chatters a lot" with a bit of concern.  At the same time, he had a fast, race winning car.  Could some chatter be the sign that your car is developing enough grip?  It may be.  I remember reading one of the late great Carroll Smith's full size racing books where he explained tire "judder" on full size formula cars.  One thing that stuck with me was not only that it was at one point a big concern to the mechanics and engineers, but when they figured out WHY it was happening , they became less worried.  It also turned out to be an indication that the driver had figured out how to get all the power down, and only the best drivers experienced the judder.

I'm not saying that a chattering car is a good thing, and obviously if the car is going nuts with the chatter, it's a negative.  I just think that maybe some amount of chattering is probably part of the nature of rubber tires, especially on high traction circuits.  To me, if the lap times are there, and the car is getting around the way you want it to, I don't think chattering is huge concern.  If it can be cured I think that is a good thing, but I'm not sure some chatter is 100% bad.