b'TECH TIP PAGE Tech Tip 61:The good, bad & ugly with aero.Diffusers need airflow to work well & provide downforce. If you have a well designed reardiffuser (and belly pan) that can seriously help airflow evacuate out from under the car at ahigh rate, your splitter needs to step up in the front. This is to allow airflow to continueflowing under the carright in the middleand out the diffuser. Or your diffuser is non- functional.On the other hand, if you have no diffuser, or a poorly designed diffuser (for looks) and/or nosmooth belly panthe under carriage isnt going to produce much downforce anyway. In thissituation, having a flat splitter that seals off the undercarriage & forces all the airflow up &over the cars body, or around) is better.The ugly:Aero is dependent on the car going forward, making smooth, gentle changes. If youget the car in a state of yaw, the downforce disappears. The more downforce you haveorhad I should saythe more dramatic the result is with this loss of downforce at speed.This is especially dangerous if you run a smooth belly pan & diffuser. When that airflow is nolonger going the length of the car, that downforce evaporates instantly. Can you say oh hell? Sure you can. LOLThe old phrase live by the sword, die by the sword is very applicable here. If you have aboatload of aero downforcesay 50% or more of your cars weightand it disappearswhen you have the car in a 10+state of yawits going to be a 90-180 state of yaw untilyou hit something.Tech Tip 62: Grip creates harmonics. Period. Anytime we create more grip in a race car, we will have more harmonics. Higher spring rates?More harmonics. Higher sway bar rates? More harmonics. Stiffer valving to control the springs & bars? More harmonics. Shortersidewall tires? More harmonics. Wider wheels & more tire pressure? More harmonics. Bigaero creating downforce and load on those springs & tires? More harmonics. Ok. Ok. There are exceptions to the rule. Eliminating chassis bind reduces harmonics. So doeseliminating stiction throughout the suspension. But, for the most part, creating race car with a high level of grip, brings a high level of harmonics with it. T his is not comfortable in the car. In fact, it is downright uncomfortable & will wear out theaverage driver in a shorter time. If the goal is to build a winning race car, the driver & crewneed to embrace harmonics as a side effect of going faster. The driver needs to be in bettershape & not complain about the harmonics to the crew. Because the only cure is to reduce grip & slow the car down. Now, if you have a track car, and driving is all about fun, you need to decide what level of harmonics are you willing to live with to outrun all of your friends. Thank goodness track daysonly run 5-15 laps, then you get a break. 544'