I have a 2007 XKR and am thinking of trading up to a new 'R'. I test drove one today and immediately noticed that the extra ~80hp makes it a lot more 'twitchy' than my '07, while it didn't feel a great deal faster (but it was a short test drive). Has anyone lived with both versions of the engine for a long enough period to give me an objective assessment of whether or not the new engine makes a lot of difference in day to day driving? Thanks!

 

If the new R was not faster then there was something wrong with it. Also, the rear end makes a world of difference.

 

If you feel you already have a surplus of unnecessary power in reserve for day to day driving, then the extra 90 hp will just make the surplus larger. If you feel you use all of your 420 hp now at times then you'll appreciate the extra. But I think the biggest difference one would notice is in the engine's responsiveness as well as low rpm torque, and the improved handling from the suspension improvements and limited slip differential. I only drive mine for fun in nice weather, but fully enjoy all aspects of its performance.

Bruce

 

Personally, I don't think I would buy a 5.0L XKR for the extra power--I'd buy it for everything else. Electronic LSD, dynamic/sport modes, full manual control of the transmission, etc.

 

I have to wonder if anyone found the XK 5.0 litre engine good enough on its own to replace a prior generation XKR...

 

I always wonder if it was a marketing issue. the 4.2 was ragged on my ppl back in 2007 being the same 10 yr old block even though it is still great. and maybe Jag had to make something different as BMW, Audi and Merc were coming out with new motors all the time.

 

My 2010 XK is noticeably more powerful than my '07 XK was. So I can't imagine needing an XKR's power...but I can imagine wanting it.

 

Lets be honest here... NOBODY is in use of the 420 hp on the street. Probably nobody is in use of the 4.2 liter without the supercharger if we are honest with ourselves.

There is more technology in the new models. Its how things work. The 4.2 cars are still awesome. The reason I got my Jag is that I love the fact that I would be happy to drive ANY 2 door jag regardless of year or power output.

 

I've never felt even a twitch from my 4.2, but in the 5.0 there was a definite lightness in the back end. That wouldn't put me off though, would just have to be a little extra cautious. Plus there are all the other benefits some of you guys have mentioned. May drive a different one next week to make sure and then pull the trigger.

 

When I drove a friend's 4.2 XKR I noticed more throw-your-head-back, low-end torque, but I felt like my 5.0 XK would catch up quick.

 

I had a 2007 XK and traded up to 2008 XKR. I noticed a big difference. When I got on the XK I would downshift 2 gears whereas when I get on the XKR I don't have to floor it as much and downshifting one gear does the trick. I drove the 5.0 XKR and hardly had to downshift it at all to get the same effect.

 

Did you find it difficult to do a burn out in your 2007 XK vs 2008 XKR? Much easier with out effort?

 

When you say full manual control of the transmission, what do you mean? Does it differ in the later models?

 

It might also have been a common complaint that the throttle pedal is not particularly linear in the first few inches of travel. The car tends to jump excessively until you get used to it (or have your ECU reflashed). I can see that that'd make the car feel 'twitchy' if you only drove it a short while. But after a week or so, you get used to it (at least I have), and you just automatically roll into the throttle more gently.

Once you've adapted, the extra torque and HP are WAY noticeable. Crushingly so... Granted, it is next to impossible to hook up from a dig with T/C off, and driving with that much power and low RPM torque with T/C turned off is like driving on ice (with bald tires!), but the power difference is definitely not subtle...

Skeeter

 

80hp is a great deal of extra power, no doubt! That's like the difference of turboing a non turbo car for reference.

 

I think it means the 2010+ doesn't up-shift at red line automatically when in sport mode, from what I've read in other threads. But I'm not totally sure.