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Can the "Speed Limiter" on a 2006 XJ8 be bypassed???

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Old 09-05-2016, 07:16 PM
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Question Can the "Speed Limiter" on a 2006 XJ8 be bypassed???
I found out that my 2006 XJ8-L has a speed limiter that limits the top speed to 120-125 mph the other day when I had to chase down a dump truck that was dropping rock and broke out my windshield when we met on a bridge.
Does anybody out there know how to change the MAP to eliminate the speed limiter and not disturb the cruise control, speed-o, in-town settable speed limiter, or any other functions of the computer? If something else controls the maximum speed I would like to address that also. It would be useless to try to make the car run faster if the top speed governor/limiter function can't be changed, so I need some expert advise on how to eliminate the top speed governor. Cheers
 
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Old 09-05-2016, 07:18 PM
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Originally Posted by Terry H
I found out that my 2006 XJ8-L has a speed limiter that limits the top speed to 120-125 mph the other day when I had to chase down a dump truck that was dropping rock and broke out my windshield when we met on a bridge.
Does anybody out there know how to change the MAP to eliminate the speed limiter and not disturb the cruise control, speed-o, in-town settable speed limiter, or any other functions of the computer? If something else controls the maximum speed I would like to address that also. It would be useless to try to make the car run faster if the speed limiter function can't be changed, so I need some expert advise. Cheers
That's not a question you really want to ask here, but if you take some time to search the board, I bet you can find an answer.
 
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Old 09-05-2016, 08:52 PM
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Also, I have read that the Top Speed Limiter is not functional if in 5th gear. Maybe be just the XJR, but I think it is all x350's.
I think it is 155 mph that is the limit. Some are 130. I have not seen 90 in many decades.
 
Last edited by Panelhead; 09-05-2016 at 08:53 PM. Reason: Spelling
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Old 09-06-2016, 02:16 PM
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+1 on the 5th gear trick
 
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Old 09-06-2016, 02:43 PM
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It may be a feature of all x350. A fellow on Audiworld took his 2004 A8 with 200,000 mile to the salt flats and ran 178 mph on street tires and mid level gas. It would only run that fast in 5th gear. Ran out of torque in 6th.
 
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Old 09-06-2016, 02:44 PM
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Originally Posted by Panelhead
It may be a feature of all x350. A fellow on Audiworld took his 2004 A8 with 200,000 mile to the salt flats and ran 178 mph on street tires and mid level gas. It would only run that fast in 5th gear. Ran out of torque in 6th.
I wouldn't even take Z rated at that speed for any period of time, especially with rubber stems.
 
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Old 09-06-2016, 09:59 PM
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I'm curious why you had to go 120mph to catch a dump truck?
 
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Old 09-07-2016, 08:10 PM
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I want one of those dump trucks!!!
 
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Old 09-07-2016, 08:49 PM
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Originally Posted by Mark in Maine
I want one of those dump trucks!!!
That's what I was thinking!
 
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Old 09-08-2016, 12:58 AM
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He didn't "have to" go that quick. It's a Jag, he chose to.
 
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Old 09-08-2016, 08:24 AM
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Originally Posted by woox4
He didn't "have to" go that quick. It's a Jag, he chose to.
;-)
 
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Old 09-08-2016, 06:44 PM
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Maybe his wife threw away his magazine stash
 
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Old 10-28-2016, 02:54 PM
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Originally Posted by anindyam
I'm curious why you had to go 120mph to catch a dump truck?
He had a headstart ;-)
 
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Old 10-28-2016, 02:58 PM
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Originally Posted by Panelhead
Also, I have read that the Top Speed Limiter is not functional if in 5th gear. Maybe be just the XJR, but I think it is all x350's.
I think it is 155 mph that is the limit. Some are 130. I have not seen 90 in many decades.
Can I change the ECU to a European model from a XJ8 (say from Germany) where they run WFO on the Autobon?
 
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Old 10-28-2016, 04:47 PM
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Originally Posted by Terry H
Can I change the ECU to a European model from a XJ8 (say from Germany) where they run WFO on the Autobon?
The only safe and legal place in North America to run more than posted speed limits is the track or the strip. If you really want to go fast in a Jaguar, sign up for one of Jaguar's driver training experiences.

http://www.jaguar.com/experience-jag...g-academy.html
 
Last edited by Box; 10-28-2016 at 04:52 PM.
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