b'TECH TIP PAGE Tech Tip 35Total Grip:Of course, spring & sway bar rates play a HUGE role in grip. Some Racers mistakenly think spring rate by itself loads the tire. These Racers have put very high spring rates in the car to load the tires, and almost dismiss the sway bars. But the final wheel load rate, accounting for motion ratios of the control arms & spring angles, are determined from the spring & sway bar combined.Were letting the cat of the bag here, so pay close attention. When a race car is sitting at ride heightrace readyall four springs are compressed to a degree. How much is determined by the cars corner weights & any cross you may have dialed into the car.Some racers call this preloading the springs. We simply call it the static spring load. NOT spring rate. Spring rate is how many pounds to compress the spring one inch. Spring load is the rate times how far the spring is compressed. For example, lets say Racer A puts 900# springs in the front & each spring compresses 3/4" at ride height. If Racer B runs the same car with 450# springs, he could expect the front springs to compress 1-1/2 each. Both of them have a static spring LOAD of 675# on each front corner to hold the front of the car up.Thats not the secret. Read on. When old school Racer A running 900# front springs & a 300# front sway barbrakes hard into the cornerthe front end dives an inch. He has added 900# of spring load to the base 675#, for a total spring load of 1575# (Not wheel rate. That would require us to calculate in motion ratio.) The old school racer doesnt see how running lower spring rate will load the tire as much.When Racer B, with a newer strategy running 450# front springs & 600# sway barbrakes hard into the cornerthe front end dives two inches. He has ALSO added 900# of spring load to the base 675#, for a total spring load of 1575#. But the front of his car (the front CG) is an inch lower than Racer A. Physics fact:A lower CG on the same track width allows higher cornering speed.Air getting under the car plays a bigger role on road courses than Autocross. But still, less air gets under the car (creating lift & less grip) when it is lower to the track.Now, under braking, they both turn the wheel to steer into the corner. The sway bar progressively adds rate into the outside front tire, until it maxes out mid-corner. Assuming Racer As car rolls 2 (about 2) and Racer Bs car rolls 1 (about 1) they are loading the sway bars & outside front tire the same. But, Racer A is unloading the inside tires & Racer B is retaining significantly more loading on the inside tiresadding total grip to the car. Shhhh! Obviously, different travel & roll angle strategies require different camber & caster numbers (statically & dynamically) to achieve the optimum tire contact patches in dive & roll. While there many spring rate vs sway bar rate strategies, if you have the right combination, your car will not only create high gripbut be very close to balanced right out of the shop. With the Ron Sutton Race-Car-in-a-Box packages, as long as your cars corner weights are within range, you should not need to change the spring rates. Your race car will have high grip & be balanced from the get-go. If we need to, due to the car coming out heavier or lighter than planned, we will exchange your springs for the correct rate at no charge (one time).238'