First you will need to decide which engine manufacture to choose. I have had HPI and Novarossi and O.S. Engines. They all come with complete breakin and tuning instructions. When breaking in your engine be sure to run it a little rich and normal operating speed (not full out more like a Sunday drive) for about 2 tanks of fuel. After that you can go for it and lean out the fuel mixture. You can get very good instructions on tuning your engine from the manufactures web sites. You should also join a local nitro car club and the guys, and some gals, will be glad to help you with any problems you may have with your car, engine, setup, tips and so on to get running smoothly. My personal opinion is I LOVE the Novarossi Engine the best.