#RACE CAR DYNAMICS CALCULATOR DRIVER#
#RACE CAR DYNAMICS CALCULATOR SKIN#

The coefficient C depends on the fender and hubcap design, as follow: Fender typeįender covers entirely the wheel (Full fender)įender doesn't cover side, wheel has flush hubcap Where W is the width of the tire and D is its diameter (see TIRE SIZE for more info). The drag coefficient (based on the frontal area of the vehicle) for EACH wheel can be estimated by: C D wheel

#RACE CAR DYNAMICS CALCULATOR SKIN#

The skin friction and internal flow are treated like all other drag ratings. ( skin friction, internal flow and the drag from all wheels ( C D wheels)) such that equation (1) becomes: C D = The method adds the drag rating for only the first nine areas presented above, and the sum is put in equation (1): C D =īased on that work, equation (1) was modified such that the base factor (0.16) could be detailed. (p336-338), which gives a drag rating (the number under each figure) for shapes of different areas of a car body. The drag coefficient ( C D) can be estimated with a method presented in Handbook of Vehicle Design Analysis Drag coefficient is at the bottom of your screen. The distance from the straight portion of the bar to the endlink attachment, measured at 90 degrees to the straight section.C D = 0.347 C DA = 7.83 ft² C LA = 3.38 ft² Drag & lift coefficients For each category, select the most appropriate choice for your vehicle. The length along the bar from the straight section to the endlink attachment. The length of the straight portion of the bar Super sensitive! Use a micrometer, and chip off powder coat! Needs to be faster than the fastest shock speed due to chassis movement.

Shock speed above which you want the curve to digress. Somewhere betwen 1.8 and 3.0 is usually right, with the rear being 0.2 Hz higher.ĭesign Damping Ratio Dimentionless, to 2 decimal places

This is a 'magic number', in that it cannot be derived.

This calculator assumes coilovers, so if your springs and shocks are not coaxial (Mustangs) you're SOL for the moment. Note this is a curve, so measure at static ride height. Get this from WinGeo, and measure directly with a pair of dial indicators and some imagination as a sanity check. Motion Ratios Dimentionless, 2 decimal places Everybody else gets the spring rate tester. Really don't forget to disconnect the swaybars! Don't forget to disconnect the sway bars!īest to weigh these directly with the sprung weight supported on jackstands.

#RACE CAR DYNAMICS CALCULATOR DRIVER#

The Calculator Inputs Corner Weights Poundsįrom your scales, with driver and average fuel load. Others, (like CG height and roll centre height) take a little more work. Some of the data is fairly simple to collect (like corner weights). There's a lot of data you have to pull off the car and accuracy counts! The key to using this application is Accurate Measurement. The remaining work on it is to provide a data entry block for your own shocks (to compare against the theoretical ideal) Yes, the graphs don't work in Internet Explorer (download Firefox already, all four of you who still use IE!) This is a web-based version (slightly simplified) of the Excel spreadsheet I designed and used to work out all the various calculations needed to

Race car dynamics calculator