Reporting a wrong result
If a tool gives an answer that doesn't match your maths, please include the exact inputs you used and the figure you expected. Every calculator on this site uses published formulas, so discrepancies are either a genuine bug worth fixing fast or a difference in assumptions worth explaining on the page. Either way it makes the site better.
Suggesting a new tool
The best suggestions are questions with one correct answer: something you've found yourself working out on paper or hunting through forum threads for. If it can be calculated, it can probably become a page here.
What not to expect
CalcGarage can't give advice on your specific vehicle, confirm whether a particular setup will fit your car, or recommend garages and products. The tools show the maths; decisions about your car stay yours.