Turbo stock top end?
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All car speedos read higher than actual speeds, that's why GPS are used for real top speed tests. Cars usually read 10% higher, sportbikes read about 15-20% higher. Before I knew about all this, I used to go like
when an old lady in a Buick pass me on my R1 when I'm crusing at 80 indicated.
when an old lady in a Buick pass me on my R1 when I'm crusing at 80 indicated.
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All car speedos read higher than actual speeds, that's why GPS are used for real top speed tests. Cars usually read 10% higher, sportbikes read about 15-20% higher. Before I knew about all this, I used to go like when an old lady in a Buick pass me on my R1 when I'm crusing at 80 indicated.
when an old lady in a Buick pass me on my R1 when I'm crusing at 80 indicated.
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nothing personal but i think i am going to have to call b.s. On this one. You are telling me that if i am doing 70 on my speedo then i am really doing 63 or 64. I don't think so. I have been zapped by radar a few times and usually the cop is within a mile or two of what i thought he hit me at. I can see some variances but i don't know about 10%
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At 80 you might be 1 or 2 mph off with a larger difference the faster you go. Id venture a guess 5pm off at 200 mph which is close enough.
At 55 my car is spot on with the radar based speed signs around these parts.
At 55 my car is spot on with the radar based speed signs around these parts.
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Nothing personal but I think I am going to have to call b.s. on this one. You are telling me that if I am doing 70 on my speedo then I am really doing 63 or 64. I don't think so. I have been zapped by radar a few times and usually the cop is within a mile or two of what I thought he hit me at. I can see some variances but I don't know about 10%
I don't know what the percentage of speedo error is on the TT, but I know it's there just like any other cars. If the speedo on cars are so accurate then why do people bother using GPS for car tests?
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Here are a couple of links I found after 5 minutes of searching on google,
http://www.caranddriver.com/features...dal_feature__1
http://en.wikipedia.org/wiki/Speedometer
With a 5% error, 200mph=190mph which is close enough to the 193mph claimed by Porsche.
http://www.caranddriver.com/features...dal_feature__1
The European regulation, ECE-R 39, is more concise, stating essentially that the speed indicated must never be lower than the true speed or higher by more than one-tenth of true speed plus four kilometers per hour (79.5 mph at a true 70). Never low. Not even if somebody swaps a big set of 285/35R-18s for stock 255/45R-16s.
There's your explanation of high-reading European speedometers, with the highest readings on Porsches and BMWs that are most likely to lure owners inclined to fool with tire sizes.
There's your explanation of high-reading European speedometers, with the highest readings on Porsches and BMWs that are most likely to lure owners inclined to fool with tire sizes.
Modern speedometers are said to be accurate within 10% but as this is legislated accuracy, this may not be entirely correct
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Dont know if this mean's anything, but I compared my speedometer to one of those police speedometer and my showed about 2 mph off. That was at 50 mph. By the way did you notice what his boost was showing at 6000 rpm? 1.1 bar. Is that right?
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Exactly
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Whether he was doing 200 or not, he seemed plenty excited enough that he got there, and I bet he is high fiving his buddies about running 200 in a 997TT. I would be too.
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Surely we don't. I just wanted some information as to variances in either direction and to ask who might know what. Accuracy is defined by each individual person.
Whether he was doing 200 or not, he seemed plenty excited enough that he got there, and I bet he is high fiving his buddies about running 200 in a 997TT. I would be too.
Whether he was doing 200 or not, he seemed plenty excited enough that he got there, and I bet he is high fiving his buddies about running 200 in a 997TT. I would be too.
My point is that it's well documented that speedometers are wildly innacurate. So a video showing a speedometer indicated 200 mph doesn't prove much. What is your point?
Here's an article that discusses the reasons for speedometer innaccuracy.
http://www.caranddriver.com/reviews/...candal_feature