I have one confirmed source and one source that seriously alludes to the fact that Jaguar is not installing the 155mph limit on the XFR. Has anyone tested this for sure to see if it really is in there?

Here is the video clip of the BBC Top Gear episode of comparing the XFR to the M5. Clearly in the one they tested there is no speed limiter. It is a great video (I searched to see if this had been posted but didn't see it). Of course, you'll need to get passed the advert for the video to commence:

http://www.youtube.com/watch?v=4JsHCCice04

Also, in the Motor Trend blurb regarding the 225.67 Bonneville run, they seriusly allude to the fact that Jag does not install the speed limiter. They make no reference to it only applying to the XFR:

" ... Most super sedans shipped to the U.S. nowadays from across the pond sport a less than generous 155 mph limited top for reasons of need, safety and efficiency. Not content with restricting its cars and their (lucky) drivers to this mark ... "

Full motor trend article is here:

http://wot.motortrend.com/6438561/au...run/index.html

Just curious if anyone can actually confirm if the XFR is limited to 155mph? Please no lecturing on whether it should be or not ... I'm not interested in opinions regarding that issue.

One day I will find out if mine is ... even if I have to find and rent a high-speed track in order to do so.

Anyone know for sure?

 

Yes theyre there

 

Saw this from Singh Autosports in Fremont, CA. Seems a little odd in that the final results for both the 470 hp and 510 hp engines are the same if both the ECU and pulley kits are used. Although they reference the XJ, I would think you could get applicable results with the XFs. However, I would defer to the experts on this.

 

I saw that Jeremy Clarkson test only today on "Dave" channel 19 Freeview. The car was on a test track, and in UK (I think). Maybe in other countries the limiter is fitted? If it is so fitted, americans will feel a little cheated I've no doubt. But how do you get round that? If it's legislation, it's legislation.
Leedsman.

 

That Top Gear video is awesome ... it was the thing that got me fully behind buying the XFR!

Note that Jeremy also states that even in the UK it is supposed to be fitted with the limiter ... yet at 165mph that car "is still accelerating" ...

Very odd indeed.

 

I was told that the 155 mph limit was part of a "gentlemens" agreement in Europe but if it is below that it is usually set to match the standard tires fitted on delivery (I have a XF Premium where the limiter is set to 121 mph - which is an odd figure since it is 194.7 kph and not some round figure). I have not checked out the limiter, but my tires are M & S all seasons H rated which have a top speed rating of 130 mph.

However I am told that the EMU is used to set the limit, so if they are exceeding the limiter, they must have someone providing them with a car with a reprogrammed EMU - the Jaguar factory maybe? - and fitting appropriate tires.

 

From what I've read and heard, the limiter only applies in 6th gear. I've seen a vid where the XFR was approaching 165ish and as soon as it shifted into 6th the limiter kicked in.

 

I know with the previous XJ (x350) there was a trick to deactivate the speed limiter. Instead of running the car in 'drive' you move it over to the j-gate and that deactivated the limiter. Whether or not the car was in top gear or not, once it was on the j-gate side the limiter was turned off.

I just wonder if there is some sort of trick like that on the XF?

 

Tricks to turn off "nanny" limiters e.g. traction control etc. usually get out on the web, especially if a TV program has used it to do strange things with a car to find it's limits.

For example, I think that if you hold down the track mode button, at least in the models where it exists, - the one with the checkered flag - for more 10 seconds or so, all the traction control is disabled in the XF). As suggested by alexsneesby, maybe there is one for the speed limiter.

Sounds more reasonable than my idea that they are using a specially modified EMU.

 

I have the 2010 XF Premium and have had several opportunities to take it up as high as it will go (early mornings on the freeways in Los Angeles). It looked liked the limiter kicked in right at 120 as I couldn't get past 125. I tried using "S" and Dynamic Control - nothing helped. Andrew

 

I don't think anyone needs to feel cheated here. Most states will nail your a$$ to the wall if you're 20mph over the limit and since most speed limits seem to be around 70 mph you have a lot to lose testing the limiter. Try that in North or South Carolina (can't remember which) and they impound the car as they do in France. In Wisconsin they consider 20 over the equivalent of a DUI so it screws up your insurance for a VERY long time.

If you do go for it you really need to know the roads (where cops wait for speedsters) and have very good sight lines a long way into the distance. You need good light, and in the Midwest places where a 500lb deer is not suddenly going to wander across the road as you're maxing it...That's going to make cat food out of the both of you.

You can try maxing it on the track but on most tracks you would never get close to that figure. Maybe just at Road America.

 

Uh ... ok ...
Since I am the OP, I can only assume your "advice" is directed at me. I thought my post was clear that I did NOT want any opinions on if the limiter SHOULD be there (the implication was to negate opinons on speeding - or so I thought).

I really don't need your thoughts on excessive speed - however - if you have any insight as to whether or not the speed limiter was fitted at the factory I am all ears (eyes) . If I ever do need your advice on how, or when, or even IF I should drive fast I'll ... oh, wait ... I don't need your advice on that at all.

Back to topic - I still find it odd that there was no limiter on the Top Gear XFR. The XFR is AMAZINGLY smooth at 140mph with LOTS of pedal left (not that I would know of course). I've "heard" that at that speed it wasn't stressed at all - it actually felt awake. Seems a shame to neuter this cat (at whatever speed the govenor is installed).

 

My post was not a criticism of excess speed - it was a comment of what happens when you get caught.

 

I didn't think that this comment was directed at any one individual, more a general observation. Certainly here in France if someone decided to drive at twice the posted speed limit and was caught, then it is bye-bye keys, driving licence, there and then + large fine and possible State sponsored holiday.

As regards the limiter Brutal confirmed in his reply that they are fitted.

Most of the high end cars we see over here, Jags, Mercs, Bms et al are limited to 155mph.

I'm not sure if this is because of safety or is more to do with emissions regulations. There are many companies in Europe that will 'Crack' the electronics to 'unlock' the car.

I had no idea that different limits seem to be applied depending on the US state.

Perhaps someone can offer more information on this.

 

On Top Gear I believe they discovered that the limiter actually kicked in at 175 mph rather than 155 as claimed. I believe they were testing the XKR at the time. So my assumption would be that when they were testing the XFR and they went past the 155mph mark it would have kicked in at 175. I know you wanted a straight forward answer, but Im fairly certain that the limiter would kick in at 175mph

 

Alex, are you sure they weren't in the "Speed pack" version?

On my Jag day out I drove both the XKR Coupe with "speed pack" and "black pack" options as well as the Convertible without either option.
Both were fantastic I have to say, but, as I understood it the "base" model ( if you can call it that ...lol ) is limited to 155mph but the "speed pack" option lifts this to 174mph.
The black pack option is all about colour options for body. wheels etc etc.....

I'm sure I posted links to all these in the spec sheets within the section if you wish to have a look

 

Oh that very well may be why they went faster than 155mph on Top Gear. Good point I completely forgot about the speed pack option

 

Well, as an XFR owner, I can say without a doubt. There is no 155mph speedlimiter on the XFR.. the 170 is what hit.

 

Nice, so that's where u topped out, or was there some left past 170 mph?

 

Were you using something like a RaceLogic data logger to verify your speed? The speedometer over reads by some considerable amount and you would need to be on the absolute flat and level to say that your speed reading was legit.