Hi guys, I just purchased a white 2015 XF Sport 3.0 RWD, which is stunning. One thing I have a question about though is the 0-60 times quoted by Jaguar. The main reason I chose the RWD over AWD is because on the Jaguar Website, they state that the RWD is faster from 0-60.

According to JagUSA:
2015 XF 3.0 RWD: 0-60 in 5.7 seconds
2015 XF 3.0 AWD: 0-60 in 6.1 seconds


Yet now, after purchasing, I see some people who have tested the AWD 3.0 XF, and they have been able to get 0-60 times of 5.3 seconds (Car and Driver) and 0-60 of 5.0 seconds (Autobytel). Does that mean I can expect to shave some time off the 0-60 time of my RWD as well, or is the AWD actually faster?

I also own AWD Audi so I was shocked to find out that in the case of the Jag, the RWD is quoted as faster 0-60.

 

There are lots of variables that enter into any "faster" equation. And you seem to mean "quicker" rather than "faster"
Road surface and tire traction would be a large variable in RWD vs AWD. I ASSUME the the RWD has enough power to smoke the tires, so that would indicate the AWD might do a quicker 0 to 60.
But, in any case, what C&D, or JagUSA, or the guy down the street gets on a given day on a given track with a given car is only loosley related to your 0 to 60 time.

 

When you add AWD to a car, you add a lot of weight and there are more things for the engine's power to have to push. There's a cost to using energy, and every piece involved in that transfer takes a share, through inertia, wobbles, etc. In a 2wd car, the engine's energy goes through the trans, drive shaft, diff, axles, wheels. In 4wd, you add another transfer case, 2 more axles and 2 more wheels. So, in general, usually a 2wd is faster than 4wd in a strictly 0-60 context, although in many other situations it might lose.

Of course, this isn't always the case. There are some manufacturers who strip some of the weight when converting a car to 4wd and do other trickery that makes it so the better initial grip of 4wd is able to overcome the 2wd's power efficiency. It can be done, but it isn't done often, from what I've seen.

 

There are a huge number of variables to 0-60. You'll see regular posts on here where people talk about how much better performance they get on a cold day, for example. Environmental and locational factors can easily influence this stuff in a big way, so you could see a huge difference in the exact same car from one day to the next.

 

It's relative to power generated by the car and traction available. The more power the engine makes, the less likely the two tires in RWD will be able to handle that power and move a heavy car from a stop.

With 4 tires to distribute the power, you'll likely get better 0-60. That does come with the caveat that the engine makes enough power that the extra weight and frictional losses of the extra drivetrain components don't limit the power output.

At your power level, it's probably as much dependent on whether you run all-season or max performance summer tires and on what surface and at what temperature. The more grip you have with RWD, the more likely you will win a 0-60 contest.

Also, the fact that the reviewers were able to clock faster times than Jag gives doesn't surprise me at all. Almost every test is quicker than the manufacturer claims because the manufacturer can't claim faster than people will see in the real world or they will be sued.

 

Thanks for the replies guys. So to simplify:

Let's say that all conditions are the same as far as tires, track surface, driver skill etc, which would be quicker to 60? XF RWD or XF AWD?

According to Jaguar USA, they are saying the RWD is significantly quicker than the AWD.

 

If RWD has traction, it will win because it has a superior power to weight and less drivetrain loss ie. more power to the wheels. The IF in that equation is the most telling. Even with my tuned car, I've lost races to a stock XFR because of traction. I gained ground due to more HP, but what I lost initially I couldn't make up.

It's a very dynamic proposal and there isn't always a clear cut answer, so I'm not trying to side step the question, just give you the factors that will make one car quicker than the other. From a roll, the RWD should win every time though.

 

I would imagine that's how Jag got their numbers. All other factors the same, including the cars being outfitted the exact same, they gave this conclusion. I don't know if they *actually* drag race to get these numbers, but I think we can be sure they arrived at them at least somewhat scientifically.
If you were comparing one brand to another and all that, then I think there would be far more question in my mind. But Jag has nothing to gain by shorting the numbers on the AWD (which is more expensive, right?). I think it's safe to assume they're correct on this.

Of course, I'm really wishing I had the AWD today.





Tiny human for scale.

 

I guarantee the AWD will be quicker than yours today!

 

>I guarantee the AWD will be quicker than yours today!

Good one.. :-D
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You dreamed of a big star -
He played a mean guitar -
He loved to drive his Jaguar...

So welcome to the machine

 

In my awd stock, I got 5.1