Originally Posted by
roosterreagan
This whole idea has bothered me since day 1 of learning about rc racing. Millions, perhaps billions, of dollars is spent in the search for torsional rigidity, both on track and the street. I've asked high level rc drivers why do we purposely "add" or account for chassis flex? They don't know, like a lot of other things in rc they "just do it, it's how it's been forever". My opinion is its lazy. Something kind of works for someone so that's it, no discussion just follow everyone else, cuz that's how it is. Period. Bull, make the chassis stiff, and tune your suspension, why else have all this great suspension technology? Why not just make it a 1/10 pan car if you're going to negate a complicated and infinitely adjustable chassis system?!
I've seen similar posts on here before, but I'm yet to see a post from someone who has made a rigid chassis and gone any quicker
The cars haven't always been flexible. They started out rigid, following full-scale vehicle dynamics. Over the years they have evolved, as chassis flex gives more grip, better bump handling and a wider setup window.
Our cars are now about 500 times lighter than the lightest full-size race car. Yet they go at about one third the speed (mod TC >70mph). And they do it with much simpler suspension, tyres and aerodynamics. And they encounter curbs that come up to their axles, and bumps that would destroy a full-size car if scaled up.
When you put all that together, it's amazing the cars get round the track at all. So they need a lot of help, and flex is one of the things that helps. It keeps all 4 tyres in contact with the track, without resulting in any extra pitch or roll.
Give an old TC3 a go. The suspension geometry is similar to a modern car, but the chassis is ultra-stiff. See how it compares to a modern car.