wheel alignment and toe-in or toe-out also affects the results...
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wheel alignment and toe-in or toe-out also affects the results...
Since most dyno runs are done with the car accelerating, not holding flat at peak power rpm, IMO the weight of the wheel would make a diffrence.
common sense if you think about your car trying to spin a 200kg wheel!
just use your imagination
:)
and i dont even know anything about dynos :D
Thx....i get my ans now.:thumbsup:Quote:
Originally Posted by bumography
i never thought thong of all people would provide the simplest logical answer :p
Simple is prefect.Quote:
Originally Posted by panda[CRX]
Bigger the wheel, slower the car.
im with Omar then - Hub dyno is most accurate...
I don't know about that cos if you think about it your gonna drive with your wheels on so technically you would want the tyres and wheels your gonna run on to give you an accurate reading with Friction otherwise your readings kinda useless unless your just trying to find how how much you could potentially make?.... Also depending on different dynos you will even get different readings! doesn't even matter if you use same car....??? makes you think aye? ;)
dynos are for tuning, not getting accurate 'readings' of your power.Quote:
Originally Posted by Limbo
as long as you keep using the same one to measure changes that you make to your engine, then accuracy doesnt matter at all... (as long as the dyno is kept to spec)
engine dyno is most accurate of all...
Was looking for info on tyre pressures, came accross this thread....
Bigger wheels require more energy to turn than smaller wheels, this is because there is more weight towards the outer edge of a larger wheel and tyre combination.
Larger Brakes also require more energy to turn.
The weight of wheels and tyres, as well drivetrain losses, have less of an effect on a car that makes 500kw over a car that makes 100kw. This is because the drivetrain, wheels and tyres only consume a certain amount of energy.
Different tyre and wheel combos will come up with different power/torque figures on inertia type dynos, where you need to measure the change in speed (acceleration) to get your power figure. But on controlled dynos where you can hold speed/rpm constant under load then there shouldnt be any difference. Things like tyre pressure will have an effect because your changing the rolling radius of the tyre/wheel so the speed will change with the same rpm.
J_Mech