boostintibby

Ive read alot of discusions online about how a mustang dyno's number are lower but more realistic/accurate then those of a dynojet .

Does anyone know a rough estimate as to how much lower the number are on a mustang dyno then to those of a dynojet?

03tibe85

As far as reading numbers at wide open throttle how a Mustang and a Dynojet calculates torque and horsepower, which is a function of torque vs RPM, is vastly different. A dynojet has a set value it uses by measuring how much force it takes to spin the heavy drums. This calculation does not take into account what type of drivetrain or weight the car has. The mustang dyno calculates torque based off of how heavy the car is, what type of drivetrain it has as well as the diameter or the drum. Both can also use a 'weather station' to adjust for conditions that might affect power.
Its easier for a Dyno operator to fudge a Mustang's numbers by messing with the variables that go into the Torque calculation. Since a Dynojet doesn't care about what car is on the dyno this makes them more consistent. The one advantage that the mustang has is that most are loaded dyno's so they are better for tuning all engine load whereas a Dynojet is better for tuning WOT and comparing WOT numbers.

187sks

From my experience, I would expect at least a 10% lower number on a Mustang Dyno.

JonGTR

This is the biggest misconception people have. Dynojets can also be loaded.

Don't believe me?

http://www.youtube.com/watch?v=ev4ajWZalDE
At 0:25, he shifts into 4th and loads it down. You can hear the motor straining.

i8acobra

Dynojet only recently made load cells available. They're still new and very expensive since they need to be bought separate and added to your old machine.

JonGTR

^^^I dynoed back in mid-2006.

03tibe85

Your right Jon, but most shops never bother buying the expensive loaded option whereas the Mustang comes with the loaded option right off the bat. There are 10 Dynojets in Colorado and not a single one has the eddy brake loaded option. sad.gif If I could afford to buy a dyno it would be a Dyno Dynamics one. Those things are liquid cooled and can tune ALL DAY without issue whereas a Loaded Mustang or Dynojet will need periodic rest periods to keep from frying the eddy brake.

JonGTR

The dyno and how it reads doesn't really matter to me, since it's really used for tuning. But the fact that there's more DynoJets out there makes it easier to compare on the interweb.

We have like 50 Mustang dynos in Texas: http://www.mustangdyne.com/LocatorPages/DynLoc_TX.htm
DynoJets, who knows. I know of at least 3-4 in the SA area. And one Dyno Dynamics for AWD.

i8acobra

2006 is recent.

03tibe85

Dyno Dynamics is the Shiz fo real. I'd be curious as to how many of those 50 dyno's are true loaded dynos. wink.gif