For far too long we have been fed this b......s about different dynos giving different readings. Like saying different micrometers will give a different measurement for piston size or diferent pumps will put different volumes of fuel into your car.
The only reasons for different readings from any measuring instrument are that one or more are inaccurate, the units on the various scales are unspecified or different, or the type of instrument used, e.g inertia v steady state dyno affects the actual power being measured.
If you take up 'Knighty's invitation and go on ebay, you will find the RPM printout for 4 engines priced at 2k each,you see that testing was done on a Rotronics Inertia dyno.( Steady state dynos take far too long to produce a graph and are arguably less representative of our use).
These printouts give a wealth of information and you can select what seems important to you.
So, bottom left we have the correction factor for atmospheric conditions. This is a correction to the actual engine power to standard temp, air pressure etc.not a correction to the dyno.That deals with 'different readings same dyno different days'
Then looking at the power and torque graphs, the power and torque axes are clearly marked as hp. and Nm, not left blank or left to the imagination.
Engine speed is in rpm. as expected but the limits for mean horsepower and engine acceleration time (secs). are clearly stated as 3000-6500rpm.
The only omissions I can see as referred to above are carb, exhaust , oil.
So that if other builders present their dyno information fully and accurately as above then dyno readings should be directly comparable from builder to builder as the results from any other measuring device would be.
As the dyno printout is used as part of the contract of sale or resale, builders and sellers need to be careful that they are not misrepresenting their product.
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