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Gig Harbor, WA

Why Competition Tuning
Dynamometer Info
Tech Info
All horsepower figures are measured at the rear wheels. This is very important because you cannot directly compare these values to those measured at the flywheel as published by the manufacturer.
The drive train in between the flywheel and the wheels consumes power, primarily through friction. In other words, power is required to turn the gears in the transmission, final drive gears, drive shafts and wheel bearings even with the wheels turning in the air.
With that said, we always produce a baseline power curve for each individual car prior to making any modifications. Since every car is different, this provides an accurate starting point for power output improvements. Thus, it is more important to note the change in values not the raw values themselves.
The computer software can store and print color graph screens showing before and after runs on the same page. It also automatically corrects for altitude and atmospheric conditions for accurate comparisons. Now you can verify the modifications done to your vehicle and take home a graph of your vehicles power curve!
Why do different Dynos record different horsepower numbers?
This can be very confusing to customers when they have their vehicle dyno'd at two different shops and come up with very different results. I would suggest that if you plan on having your vehicle on the dyno often that you are very selective about the shop you choose and stay with that shop.
Why are the numbers on any loading dyno always LOWER than on a dynojet dyno?
Dynojet 248C is actually an accelerometer whereby it uses a 3000-3200 pound drum that is used to create an inertia load on the vehicle being tested. The vehicle's horsepower (HP) and torque try to overcome the weight/inertia of the drum to accelerate it. As a result the software and electronics try to measure the horsepower and torque that the vehicle is developing to overcome the drum's weight and inertia. The resulting horsepower and torque will be higher than a true loading dyno because once the drum starts rolling not as much power is needed to keep it going. Example -- When pushing a car on a flat road, once the car starts moving not as much power (effort) is needed to keep it going. The software does not ask for vehicle weight or anything like horsepower needed to maintain 50 MPH (a number that is actually put out by E.P.A. and N.H.T.S.A.).