[torsen] RE: [urq] RE: RS2 turbocharger

Martin Pajak martin at quattro.ca
Thu Jun 13 14:22:17 EDT 2002

There is an easy solution.
If you know vehicle dynamics there is a few equations that give an exact
difference in acceleration of a vehicle knowing the specs of the two
flywheels i.e. moment of inertia weight, radius of gyration, diameter.
We did this in school to prove that it is better to invest in lighter
flywheel rather than lighter wheels (through gears the effect of inertia
decreases, especially in lowest gear).
In both cases acceleration at specific rpm is the only one unknown, given
are: power at RPM, Overall gear ratio (drivetrain losses), tire diam,
tire/road friction coef (for quattro you can assume no slip), rolling
resistance, weight of the vehicle, air resistance(you know speed through
gear ratio, rpm and wheel diam.) and gradiant if there is one.
Not taking any sides, just providing a possible solution to an endless

Martin Pajak


1983 Audi Ur-quattro (269,000 km) Canadian spec. winter car
1985 Audi Ur-quattro (146,000 km) Euro spec. import ;o)

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