thatsnowinnebago wrote: In reply to volvoclearinghouse: I think its more that those three give a ton of downforce so then the car needs more spring to compensate. Hopefully one of the smart folks around here will chime in with a better answer...
Also less bar and more spring (some people even go so far as to remove the bars completely) helps the suspension to keep the tires in contact with the road surface. Large bars tend to cause inside tire lift and/or eliminate droop travel, something that can be fairly important with tracks that have a lot elevation changes, reducing radius corners, etc. where you need every inch of friction material on the ground.
The trade off is that hugely stiff springs do not ride very well (even when paired with proper dampers), so the compromise for those situations where comfort is desired, is to use softer springs and dampers for ride quality and then fine tune roll and transitional response with the bars.
Depending on the variables involved (track configuration, chassis/suspension design, driver preference, etc.), typically for a qualifying lap you want the car a bit more stiff to allow the aero to work as effectively as possible and improve transitional response at the expense of requiring much more precision with the driver inputs. For the actual race, some people tend to run their cars a little softer to allow for more flexibility when driving off the line or driving in a pack of cars and to make the driver more comfortable.
