Used P85 or 85D?

[sorka]

The RWD version is much harder on the rear tires.

Or more specifically why?

 

[jelloslug]

Or more specifically why?

More torque on that axle.

 

[sorka]

More torque on that axle.

But no torque on the front axel....during acceleration and regen braking.

Going to throw you hint. What you said WOULD be true if you were doing burn outs or frequently losing traction on the rear wheels while accelerating.

 

[jelloslug]

But no torque on the front axel....during acceleration and regen braking.

Going to throw you hint. What you said WOULD be true if you were doing burn outs or frequently losing traction on the rear wheels while accelerating.

OK

 

[LCR1]

But no torque on the front axel....during acceleration and regen braking.

Going to throw you hint. What you said WOULD be true if you were doing burn outs or frequently losing traction on the rear wheels while accelerating.

And the P85 is constantly losing traction and the traction control constantly kicks in when I'm driving it vs the D.

Also, losing traction is irrelevant to the discussion so your point is moot. Go back to the basics and you'll understand why having all the traction in the world also means you're tearing through tires.

 

[sorka]

And the P85 is constantly losing traction and the traction control constantly kicks in when I'm driving it vs the D.

Also, losing traction is irrelevant to the discussion so your point is moot. Go back to the basics and you'll understand why having all the traction in the world also means you're tearing through tires.

The same amount of shear force is applied to rear tires or the P85 as to ALL tires of the 85D combined to effect the same change in momentum.

If you want to split hairs, considering only straight line changes in momentum, the 85D is wearing through tires faster for the same rates of acceleration and deceleration because it's heavier than the P85.

If you don't rotate your tires frequently, you'll destroy the rears tires much faster than the 85D since the 85D is splitting torque between the front and back. But if you do rotate, you should get just a bit more mileage out of the P85. If you have a staggered setup on the P85, you'r screwed unless you're willing to replace rear tires only without doing the fronts at the same time.

 

[sorka]

Somehow I lost the first line of my last reply.

The decrease in wear on the rear wheels for equal acceleration of equal mass is simply transferred to the front tires on the 85D. The front tires on the 85D will wear faster than on the P85.

 

[LCR1]

There's also the very real differences in tire wear from pushing vs pulling.

 

[sorka]

There's also the very real differences in tire wear from pushing vs pulling.

Not pushing vs pulling but certainly which axel as the front axel tends to unload while the rear loads more. Front axel only cars will lose traction more easily which will certainly accelerate wear when comparing apples to apples (i.e. equal weight, power, etc).