The more you modify your vehicle, the more beneficial it is to have your car custom tuned to match your vehicle's exact modifications.  From the factory, the Air-Fuel Ratio (AFR) is usually set up very conservative so there is a benefit to dialing in the air-fuel ratio to be optimized to the perfect level depending on your engine and mod list.  We still keep the air fuel ratio at a level so it is perfectly safe for the car, but we have the benefit of measuring your actual car's air-fuel ratio in real-time so we can make the AFR be exactly as rich as it needs to be for it to be completely safe, but not too rich to take away any power.  The factory does not dyno-tune every vehicle, so they make one tune and use it on thousands of cars, which is why they have to be conservative, because they don't know all the variables, so they have to guess on the safe side.  Factors like the exact composition of the fuel used, the actual frequency of the Mass Air Flow at a given air flow rate, the actual flow rate of your injectors compared to what is programmed into the pcm ... these are just a few of the kind of variables that affect your theoretical air fuel ratio.  When you modify your vehicle, it increases the chance for error even more.  So once you've installed all your new modifications, that is a good time to recalibrate the pcm to optimize the air fuel ratio, not only to make up for the error in the stock pcm, but also to set it up for all the modifications that you've done.  Using a dynomometer is a great place to do this because it allows you to run the vehicle at wide-open throttle for as long as you want (or are able to), at whatever speed you want, (something you really can't get away with on the street, atleast without getting arrested), and you're doing this in a controlled environment where you can monitor whatever systems you want during the runs, and even take physical measurements off the engine during a pass.  The MMS Dyno Tune includes one of our Custom-Tuned PCM's.  We can even send it to you ahead of time, so you can drive the vehicle to us to be dyno'd.  The MMS Dyno Tune also includes two hours of dynotuning with wideband AFR monitioring, as well as a street-tune after the dyno to dial-in the part-throttle tuning.  Depending on your engine's modifications, we may need more time than this, some options will raise the price a little.  We also offer a discount on the Dyno Tune if you already have one of our other PCM tunes.

When do I need a Dyno Tune?  On a 3800 Engine, we recommend a dynotune whenever you install a setup with atleast aftermarket heads and cam.  Just because the engine is supercharged doesn't mean you need a dynotune right off the bat, so regardless of supercharged or not, we recommend a dyno tune after you install heads and cam.  On a 3100, 3400, or 3500 engine, we recommend a dynotune after heads and cam, but we also recommend a dynotune any time you add a supercharger, or turbocharger to the engine.  Any engine with nitrous should be dynotuned to ensure it will stay in one piece.

How much more power will my car make on a dyno compared to your off-the-shelf tunes?  It really depends how closely your engine is running compared to how the pcm expects it to be running.  On our mail-order tunes, we don't change the AFR on our pcm tunes unless we have wideband data, so by leaning the car out to the proper AFR on the dyno, this usually helps add a little power.  Sometimes we can also increase the timing more than usual depending how the car is running, which can give me power.  Most cars will make 5-15 more hp on the dyno compared to our standard pcm tunes, although some can see more.  Our boosted pcm's for the 3100, 3400, and 3500 engines are designed to be very conservative, and be able to be close enough to run the engine for a while and be safe before you can get to the dyno to tune it a little more aggressively.  The AFR is a little rich, but timing advance is signifcantly reduced.  We do this in case the customer accidently goes over the desired or expected amount of boost, so they don't immediately blow their engine.  When we dynotune one of these boosted 3100/3400/3500 cars, or any car converted to turbocharged, we typically pick up much more power, especially with the ability to add boost as well as timing.