This statement is inspired by veg oil but applies to any change that you may want to make to your car or anything else.
When you change something, you are attempting to be a one-man research and development team. You are responsible for considering all of the variables involved, the forces of nature, the materials and the safety of yourself and others. You are responsible for testing and proving your modifications. The chances of success vary wildly on this type of project and there are almost always compromises. If you are not aware of the problems that you will face you have little chance of success.
One constant is that you can take almost anyone who can get his hands on a hammer, a hacksaw and crescent wrench and he feels like he is gifted and can improve on the best of designs. He becomes even more gifted when he can get his hands on power tools and torches.
Some things are minimally engineered to start with and look like they can easily be improved. The truth is with these designs often there is less margin for guesswork and by changing it you compromise the original design beyond the limits of safety or sanity.
Before you hack-up your next project, think about the rest of us and realize that you are where you are only because of those who came before you. They are the ones who put you where you are, it was not your inherent genius.
There are many charismatic people who can easily convince you that they have all of the answers. One of the signs that you have met one of these people is that they want your money or want your respect or approval. Often they appeal to a higher authority or higher level of morality.