A digital borescope is a great tool you can use to quickly and clearly diagnose engine problems for your customers. At $350, the Vividia AbleScope VA-800 USB Borescope is an excellent buy and a useful tool for any performance shop.
It's a great idea to document any damage you encounter while working on a customer's car. My Shop Assist allows you to upload photos to a task (such as Diagnose Engine Failure") so you and the customer can reference them at anytime.
This tool is great for quickly determining the origin of the engine failure. No more guessing on what broke and allows you to quickly generate an estimate to fix the issue for the customer.
You can purchase this product from Oasis Scientific by following this link.