Q&A Forum
Hi Jostein and everyone.
I have been using wrong sizes and weights to sort of calibrate the dyno to give credible results. But since this science, i really would like some hep to confirure the Dyno correctly to have the best results.
I have this RPM capture that i show on the pictures:
My trigger whell has 12 tooth and the 63cms diameter roll and im not sure but it weight around 600kg...
When i put this info on the inertia setup, the values go very strange, ando now i have configured as 75cms dameter, 1050 kg roll and 13 teeth. it measures ok like this but i really want it setup up correctly.
Can you please help me identify what i have wrong? thank you.
Hi,
First thing to correct is the number of teeth. You have to set this right, otherwise all measurements will be wrong.
Next is to know the MOI of your rollers. If you don't know the weight of your rollers, then you need to estimate it. There are calculators on the web where you can calculate the weight from measurements and the known density of steel. It will get you closer, but of course nothing beats measuring the true weight. Then there are MOI calculators where you can put more complex shapes, include axels, etc. You also need to add the MOI of the car's wheels and drive train.
Alternatively, test a car on a calibrated dyno, and test it again on yours and adjust the MOI to match.