A rebuilt or remanufactured engine has some inherent advantages over a conventional engine. The most immediate is that it makes for better fuel economy and reduced emissions. Precision Engine Rebuilders is a company that specializes in such engines. The available rebuilt engines are split into three main categories. They are marine engines, performance engines, and replacement engines. Besides listing all the corresponding engines, each page includes a section whereby customers can ask engine-related questions, such as engine size, year and model, as well as performance details. On the other hand, there are engine rebuild kits for sale. These include oil pumps, gaskets, seals, rings, and bearings. Likewise, engine crank kits can be purchased, and they come complete with reground crankshaft, main, and rod bearings. Other available products include domestic cylinder heads. It is worth remembering (as the site points out) that when it comes to engine cranks kits and cylinder heads, they are mostly done on special order, so it is necessary to ask a salesman for further information.