[Ron Sutton]

Originally Posted by Build-It-Break-it

Hey Ron, It looks like the rear lower control arm mounts are slotted? How does that set up work and what purpose does the adjustability serve? Excuse my ignorance......

Hey Ahmad ! Most people outside of racing don't know why we do it.

By the way, we only slot the front lower link mounts on the crossmember. The lowers are pushing under acceleration, so the slot is not at risk of pulling out. The forces under decel are not as hard on it. We slot them to get the lower links perfectly level with the car at the desired ride height & rake. When the lower link are level (regardless of upper link angle) the car has zero rear steer during roll. That's how we start all of our clients.

Then if they need a little extra help turning on some crazy tight AX courses, They can adjust the front of the links up some ... creating "positive rear steer" ... and helping the car to turn better. This is at a cost of some rear grip under throttle, so we don't want to do it if it's not needed. On road courses, or super fast open road races like Silver State, Big Bend (which our client Tom Whelen won both at 204 & 205 mph averages) we can do the opposite. By lowering the front of the lower links, we're creating "negative steer" ... which adds rear grip the faster you go through corners. The downside is it doesn't turn tight as well.

So the slots are just a tuning tool to make sure we're neutral rear steer, positive or counter ... as we need.

P.S. ALL RSRT 3-Links & Torque Arms come with these slotted brackets for the lower links.