The new 2011 Formula Drift rulebook has been released today and one of the bigger changes to the rule book fall into this 9.1 section that covers Tire Size Regulation and a new weight/tire chassis rule. I think this is a fantastic rule to keep teams from strip weighting their vehicles and running a huge tire in the future. This should effect some of the bigger teams in the series for the 2011 Formula Drift series.

i really like it it will be good to see cars brought to somewhat eveness... it will also help stop the 8000000 hp v8 mx5 size cars from being made...


TIRE SIZE REGULATION
Cars are limited to the size of the rear tire that can be used, depending on the weight
of the vehicle. There are 7 weight classes, each spanning 200 lbs. A car must be
track-ready, and running when it is weighed and registered to a weight class. A car will
be weighed without the driver, and once the car is registered to a weight class, it will
be recorded, and issued a class-specific sticker that must be displayed prominently on
the windshield. A car’s weight may fluctuate within the limits of it’s weight class, but it
can never weigh less than the minimum weight for its’ registered class. Tire sizes are
AS MEASURED in mm, across the span of the contact patch. Tires will be measured
on the rim, while on the car, while the car is on the ground. Tire size must not exceed
the maximum size dictated by class at any time on track. Tire size will be measured
and verified on track before the start of every tandem round. A Formula D official may
also check tire size at any time during the event.



Weight and Tire Classes-
2000-2199lbs up to 215mm tire width
2200-2399lbs up to 235mm tire width
2400-2599lbs up to 255mm tire width
2600-2799lbs up to 275mm tire width
2800-2999lbs up to 295mm tire width
3000-3199lbs up to 315mm tire width
3200-3399lbs up to 335mm tire width