I thought I read someplace that the S electronic speed limiter was at 158 and the journey/x limiter was at about 135. Somebody or other mentioned that this had to do with the speed ratings of the stock tires. Journeys and Xs come with V rated tires (149MPH) and Ss come with W rated tires (168MPH).

just to tell everybody my 07 g35s sixspd sedan on sunday coming back from skyline drive hit 1200 miles and 135mph easily then this morning i read this thread and said hum ive got to prove this wrong. well with a nice stretch of highway and my passport helping guard me i jumped my car right up to 140mph maybe 143mph not sure... the 07 G35s sixspd sedan is not governed to 135mph, im positive!
JJay

I just did 140~145 today (in the early morning around 3:30~4:00). I think I could have pushed a bit further, but I had to get off the ramp so I slowed down... BTW, I have a Sport with 5AT.

While driving down to Florida on I-75, there was a stretch with little traffic with clear sightlines where I hit 120 with ease. But it was only for a few seconds and I couldn't resist testing it. And let me say, I am surprised that the top speed is only 135 because it went to 120 with surprising ease and the pedal wasnt even all the way down. I personally drive 75-99 on highways. At 110, you hear a slight whistling noise (i am not sure if it is coming from contact of the tires with the pavement or what). Personally, I am for speeding, but the main factor which discourages me from exceeding 100 is the fact that the other cars have a more dangerous habit than speeding - NOT USING THEIR FREAKING TURN SIGNALS. And cops are too lazy to ticket most driving infractions other than speeding. And cops need to priortize speed enforcement according to the conditions. If I am speeding around a bend, then there is a chance I won't have time to recover if there is a stranded motorist on the road. Same with bad weather conditions. Shouldnt cops be ticketing speeders more in the rain? THe fact that cops dont do that shows they do not care about speeding, but revenue generation.

If they ever get an autobahn, I think there should be zero tolerance for bad driving. Cops should strictly enforce all non speed related infractions like tailgating and lane weaving and not using turn signals for lane changes.

OK, makes sense, but my Journey came from the factory with the sport wheel/tire option so with W rated tires would the limiter be set to match the tires? Is this sort of data available via the diagnostics or can the dealer determine it some other way - other than a road test? Would be a bit safer than testing it out directly, at least for now.

I would have to agree with you on that one. I can't wait to get back to Japan. Driving their was fun