b"TECH TIP PAGETech Tip 63: Locker DifferentialsWhen you have the right spring rate in a locker, no differential works better. Why do we saythat?All other differentials split the power to the inside tire & the outside tire by somepercentage. Some are 75% & 25%. Some are variable. Regardless, any power split other than 100% & 0% is not optimum in the roll through zone of the corner, when you are off throttle. On track, with the hammer down, we want 50/50 power split to the rear tires. When we comeoff the throttle, brake & turn into & through the cornerwe need one tire to be 100%completely disengagedand the other to have full drive. (Remember, the power is off.)If one tire is not fully disengaged from powerlike what happens with clutch posis & helicalgear differentialswe are contributing to a tight/push condition. We would have to tune thesuspension to give up rear grip mid-corner, to make the car turn well. This would reduce our grip on exit, when were under throttle. When we go to the throttle, we dont want 75/25 oranything other than 50/50. Only a locker is 50/50 under power & 100/0 when turning. That is optimum. It just requires thecorrect spring rate. Detroit Lockers come from the factory with a 78# spring, which is too stifffor most road course applications. Locker spring rate recommendations are:Up to 12.5 slicks with moderate aero downforce = 40# 13 & larger slicks with moderate aero downforce = 55# 13 & larger slicks with high aero downforce = 65#A ton of racers have dialed in their lockers with the right spring rate & swear by them. A lot ofother guys have tried lockers, had problems and swear at them. LOL This part is simple. If the locker spring is too stiff, it wont unlock in the corner. Then justabout any diff is better. If you have the right spring & disengage one wheel through the corner no diff is better. Hey!Heres an idea!Lets put the right springs in your locker!Tech Tip 64: This may sound funny, but Ron Sutton does NOT KNOW what spring & swaybar rates a race car needs without running computer calculations & simulations based on each race car's specifications & geometry. There are too many variables & these variables matter.Common variables that matter:Wider track widths require less sway bar rate than narrower track widths A lower CG requires less spring & sway bar rate than cars with higher CGs A lighter race car requires less spring & sway bar rate than heavier cars Lower roll center cars require less sway bar rate than cars with higher roll centers Cars with higher front end dive travel under braking require softer springs Cars with lower roll angles when cornering require higher sway bar rates Cars with higher anti-dive in the control arms require softer front springsAll of specifications & geometry parameters that vary, affect the optimum setup. A great setupcan not be created without knowing these & taking them into account. 545"