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Nimisys · 11-11-2004, 08:00 PM

hardly.

look at the traction issue this way.

a tire has a limited set amount of grip that can be divided in two forms. one is road holding and one is power delivery. whe 75% of a tires total grip is being used in road holding that leaves UPTO 25% aviable for power delivery. if the power being applied to the wheel would be 50% of a tire grip under normal conditions, but used in this instanse your 75% toward road holding + 50% of power delivery exceeds 100% and you get a tire that slips. you lose a portion of roadholding and a portion of power delivery to the point where total capacity is 100%. overlysimplified? yes, but the idea behind it is sound.

where awd has the advatnage is that it allows power delevery to be divided amoung 4 tires instead of just two, so instead of the tire using 50% of its gripping capacity for power delivery its using only 25%. so int he example above the tire would not have slipped. however using the same example (from the first paragraph), if 75% of a tire is being called on for road holding, but only 10% of it is being asked to do power delivery, then it will still not slip, regardless of how many other tires are being asked to share the load.

So AWD setup SOLE advantage is in extreme tracion areas, IE rally racing and inital take off of a vehicle. you can divide your power output across more tires. however when the amount of traction avialbe is suffcient for power delivery and road holding to occur within the limits of the tire, there is no advatnage to splitng your power distrabution amoung additional tires. when this is the case (as it is in the majoity of the time in on-pavment racing) the advantage of a lighter drivetrain and more effceint transfer of power becames apparent.

in general during ideal race conditons on a pavement cource, an awd vehicle will require additional horcepower to match an otherwise identical rwd vehicle. the losses due to weight and rotational mass are large enough to cause a descrepency in performance. again awd has the advatnage in that it can divide its power delivery across a broader range of tires, however this only applies when traction is liming the power delivery across only two tires.

11-11-2004, 08:00 PM	#159 (permalink)
Nimisys Crazy Location: San Diego	hardly. look at the traction issue this way. a tire has a limited set amount of grip that can be divided in two forms. one is road holding and one is power delivery. whe 75% of a tires total grip is being used in road holding that leaves UPTO 25% aviable for power delivery. if the power being applied to the wheel would be 50% of a tire grip under normal conditions, but used in this instanse your 75% toward road holding + 50% of power delivery exceeds 100% and you get a tire that slips. you lose a portion of roadholding and a portion of power delivery to the point where total capacity is 100%. overlysimplified? yes, but the idea behind it is sound. where awd has the advatnage is that it allows power delevery to be divided amoung 4 tires instead of just two, so instead of the tire using 50% of its gripping capacity for power delivery its using only 25%. so int he example above the tire would not have slipped. however using the same example (from the first paragraph), if 75% of a tire is being called on for road holding, but only 10% of it is being asked to do power delivery, then it will still not slip, regardless of how many other tires are being asked to share the load. So AWD setup SOLE advantage is in extreme tracion areas, IE rally racing and inital take off of a vehicle. you can divide your power output across more tires. however when the amount of traction avialbe is suffcient for power delivery and road holding to occur within the limits of the tire, there is no advatnage to splitng your power distrabution amoung additional tires. when this is the case (as it is in the majoity of the time in on-pavment racing) the advantage of a lighter drivetrain and more effceint transfer of power becames apparent. in general during ideal race conditons on a pavement cource, an awd vehicle will require additional horcepower to match an otherwise identical rwd vehicle. the losses due to weight and rotational mass are large enough to cause a descrepency in performance. again awd has the advatnage in that it can divide its power delivery across a broader range of tires, however this only applies when traction is liming the power delivery across only two tires.