There are several kits you can buy, you have to decide if you want engine or chassis dyno. Once you decide that, you have the big ticket item, the drum/flywheel, which has to be machined and balanced expect to pay about $3-5k alone for that. Then there is the exhaust fans and ducting, and finaly a often overlooked area of silencing exhaust noise. Dyno's are useless for jetting. In order to apply a load to the engine you have to have a brake that is either electric or water, water brakes are a PITA. So your back to an inertia, with inertia your at the mercy of the software to find if the results are useful or not. SportDevices and Dynertia. After all that buying a used dyno will seem like great value, one sold recently on ebay for $8k( had wildly inaccurate outputs, but any dyno can have that). A alternative is a Iphone and the dynolicious app that even on 650hp cars is within 3-5hp.