Originally Posted by mnavarro
Secondly, I think there's some confusion about the use of the mustang dyno to record hp when dyno tuning vs inertial dynos like dynojets. For tuning sessions it is appropriate to enter the hp@50 mph to simulate the load of real world driving. I've been told these numbers affect torque curves more than outright hp, but nonetheless should be considered less important when measuring outright hp.
Excellent point. The HP@50 (as I have experimented with), causes the Mustang dyno to add additional load as speed increases. In my experimentation, changes to thge HP@50 make a greater change in measured high end hp, while changes to the base weight changes low end torque more. If I set the HP@50 to something like 50, (it is usually something more like 13), the car runs the pull fine until about 5000rpm, then it starts to slow to a crawl and eventually can't even finish the run.
Equally, if you set the weight to 8000 lbs, the car can bearly get above 2500 rpm as it tries to fight against the load.
The mustang also has a rpm hold mode, which provides an equal force against the car to keep the RPM consant. That works very well for a steady state measurement of HP, and of course for tuning.