Dyno Jet/Mustang Dyno

[Jeff Chambers]

Originally Posted by Unit 5302

The Mustang Dyno is a more complex measuring device that supposedly takes into consideration vehicle weight and aerodynamics. It often reads significantly lower than other dynos.

I think it's a bunch of crap, myself. There was a rather intense debate about it some years ago involving myself, jimberg, and a few others. Might try digging it up.

Yep, that's a bunch of crap. How does one know that the Dynojet isn't reading falsely high? Ask MD to explain how TQ/HP are measured on their machine then ask the same of Dynojet. You'll get two completely different answers, and two answers that says the 'other guy' is wrong. I just bought a Mustang Dyno MD-1100-SE and its a fantastic machine. If someone wants me to lie to them and pump their numbers up, I'll just add a scalar. Read low/read high, 99% of customers wouldn't know the difference if there was a random number generator spitting out the numbers. No offense intended, but there's not many out there (myself included) that really understands the physics and mechanics behind the measurements being made.

The important thing is to use the same dyno consistently to get a good reading on how much your changes have netted (+ or -). No two dynos will read the same, and no one dyno will read the same every time, every day, every run. There's too many variables involved no matter what dyno you're on.

BTW: The MD will only use the aerodynamic loading in certain test formats (e.g. 1/4-mile run). For a typical power curve, no aero loading is applied.

[HotRoddin]

Originally Posted by Jeff Chambers

How does one know that the Dynojet isn't reading falsely high? Ask MD to explain how TQ/HP are measured on their machine then ask the same of Dynojet. You'll get two completely different answers, and two answers that says the 'other guy' is wrong.

That is mind boggling to me. I know only the basics of dynos, but every other measuring instrument known to man has some point of reference that it's measurement is based on ... any micrometer can be checked with a precision machined block, traceable back to a standard ... torque wrenches, even cheap ones, have to have some degree of measurable accuracy. 1 HP is a measurable thing, tracable back to a highly accurate standard, it's not some arbitrary number that someone sets where ever he feels it should be ??? What am I missing here ? How can these machines read something totally different, measuring the same thing.
Websters definition of measure ......
Dimensions, quantity, or capacity as ascertained by comparison with a standard.

Please somebody enlighten me here.