RC Oil Weight Guide
RC suspension oil changes how a model lands, turns, and holds grip. A thicker oil slows piston movement. A thinner oil lets the shock move faster. Many racers talk in weight values. Many bottles also show centistokes, or cSt. These scales are not identical across brands. This calculator gives a practical bridge between them.
Why cSt Matters
Centistokes measure kinematic viscosity. It is a physical value. It lets you compare oils with less guesswork. Weight is a hobby label. One brand's 35 weight may not match another brand's 35 weight. That is why the tool uses a reference curve and a brand factor. You can adjust the factor when your oil line feels different.
Temperature And Track Feel
Oil becomes thinner when it gets warm. It becomes thicker when it gets cold. A car tuned in a cool room may feel softer outdoors. The temperature correction estimates that shift. It does not replace testing. It helps you predict which bottle may feel close after conditions change.
Using The Mass Estimate
The calculator also estimates grams from milliliters. This helps when you fill shocks by weight, log oil use, or plan pit supplies. Silicone shock oil is usually close to one gram per milliliter, but density changes by product. Enter the bottle density when it is listed. Otherwise, the default gives a practical estimate.
Better Setup Records
Use the CSV and PDF options after each run. Save the oil, temperature, piston data, and notes together. Over time, your setup sheet becomes more useful than a single conversion. Compare results after jumps, bumps, and long runs. Small changes are easier to understand when every test is recorded.
Reading The Result
Start with the equivalent cSt and weight. Then check the corrected viscosity. The damping index compares your oil with a common 30 weight baseline. A value above one means slower shock action. A value below one means faster action. The piston flow index adds hole size and hole count. It is only a guide, because piston shape, shaft speed, seals, and air volume also matter. Use it to compare your own changes, not to judge every car. It keeps tuning simple when several oils look similar on paper.