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## Main Question or Discussion Point

I want to settle an ongoing debate that has plagued some car forums I have been on for years.

Scenario:

-A Rear wheel drive car; 1996 M3 @210whp, against an AWD 60/40 transfer case ratio 2004 STi @220ish AWHP.

-0-100mph race the STi wins (AWD duh)

-if started at 100-150mph the M3 wins (RWD duh)

-Drag coefficient of the STi is .29, M3 is .32 (advantage STi)

-Final Drive gearing is near the same

Basically those details above aren't really important; What I'm trying to prove to these guys is that an AWD car (with a set distribution of power [60rear/40front]) will encounter increased loss of wheel power as the speeds increase and the engine fights to put down power through all the gears and driveshafts. The RWD will suffer from the same losses, just not as much due to having less gears, less driveshafts, and less half shafts.

What I'm looking for is a theory, or equation that proves this. I know for a fact that a RWD car with less whp will be faster from this 100-150mph run than the AWD car with slightly more whp (how much more till the AWD car is the same speed [in time], I do not know).

For the record; I do my racing on the track (the 1996 M3 being my own). This is just to prove to some of the dyno whp brainwashed guys that think a whp number is the end all be all of real world performance figures.

Please don't include AWD super car examples that transfer upwards of 100% of the power to the rear wheels to take advantage of RWD superiority at speed. I already know this is why those manufactures do this and using this example to some of the simple minded folk on said forums doesn't go far :(

Any help sorting these guys out will help a bunch, I already know I'm right, just lack the equations and terminology to prove such. :)

-Brett

Scenario:

-A Rear wheel drive car; 1996 M3 @210whp, against an AWD 60/40 transfer case ratio 2004 STi @220ish AWHP.

-0-100mph race the STi wins (AWD duh)

-if started at 100-150mph the M3 wins (RWD duh)

-Drag coefficient of the STi is .29, M3 is .32 (advantage STi)

-Final Drive gearing is near the same

Basically those details above aren't really important; What I'm trying to prove to these guys is that an AWD car (with a set distribution of power [60rear/40front]) will encounter increased loss of wheel power as the speeds increase and the engine fights to put down power through all the gears and driveshafts. The RWD will suffer from the same losses, just not as much due to having less gears, less driveshafts, and less half shafts.

What I'm looking for is a theory, or equation that proves this. I know for a fact that a RWD car with less whp will be faster from this 100-150mph run than the AWD car with slightly more whp (how much more till the AWD car is the same speed [in time], I do not know).

For the record; I do my racing on the track (the 1996 M3 being my own). This is just to prove to some of the dyno whp brainwashed guys that think a whp number is the end all be all of real world performance figures.

Please don't include AWD super car examples that transfer upwards of 100% of the power to the rear wheels to take advantage of RWD superiority at speed. I already know this is why those manufactures do this and using this example to some of the simple minded folk on said forums doesn't go far :(

Any help sorting these guys out will help a bunch, I already know I'm right, just lack the equations and terminology to prove such. :)

-Brett