a torque wrench is what you will need to assemble an engine, as every bolt has to be torqued. Torqueing means to tighten a bolt to a certain specification. Almost all engine manuals or hotrodding book will have a page with all the torque specs for all the bolts on that particular engine. Torque is usually in ft.lbs.. This is the amount it takes to stretch the bolt a certain amount. There are different style torque wrenches, but the most common nowadays is the "clicker" style. You rotate the handle to what ever amount of ft.lbs. you need. Then you tighten the bolt until you hear the click, which indicates you have reached the figure you dialed in on the handle. You can buy at a parts store or can usually rent a a rental store. You will need one that goes from 10 ft.lbs. to 150 ft.lbs. Can buy a cheap one for around $60.00 or a better one will run about $125.00. Hope this helps. Hope I explained it well enough.
