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I am perfectly aware you said it i was just explaining it to him better.
Technical GPS 1.9 Multijet top speed
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Technical GPS 1.9 Multijet top speed
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THE POLICE GUIDELINES said:
clearer? as thats taken directly from ACPO document.
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I know what the laws are.
OP
OP
Oi Stripes!Originally posted by: Stripes
lol, nah actually I actually was over there. Nowhere around here to do that on the road, police buzzing everywhere!
North Weald is only a small airfield and planes don't run out of there late, so can easily get on there in the evening
I can believe it, was still pulling like a b*tch at 115....but I wonder what damage it is doing to the engine/turbo doing 141! Surely the oil won't get around it quick enough. Must be sitting at about 4000 revs?Originally posted by RossHutchie
The M-jets will fill the clock and more after a remap. Your right about the clocks over reading, the most ive seen mines at on the Sat Nav is 141mph with still a little revs left
P
Just for the record, and to aid in the discussion. I have now checked 3 separate cars speedos against actual speed using a laptop based GPS system (TomToms and the like I have found are too inaccurate and have too long a lag time for an accurate reading).
From new all 3 cars, VW Golf Mk4 2001, Volvo C70 2000, and my 2008 GP all gave an actual speed around 48mph +/- 0.5 when the speedo was reading 50. (Original tyre sizes and recommended tyre pressures)
As far as I am aware by law, and to pass an MOT the speedo must read within 10% at any time. Yes it is probably true that from new all cars over-read, but doubtfully not by as much as 10%. I find it unlikely that the starting point for any manufacturer would be at the extreme lower end of the limit otherwise any slight change in the variables of tyres would push it outside the legal limits. Such things as fluctuations in tyre temperature, vehicle weight, centrifugal forces and tread wear could all change the overall rolling diameter of the tyre, and therefore the reading on the speedo.
From new all 3 cars, VW Golf Mk4 2001, Volvo C70 2000, and my 2008 GP all gave an actual speed around 48mph +/- 0.5 when the speedo was reading 50. (Original tyre sizes and recommended tyre pressures)
As far as I am aware by law, and to pass an MOT the speedo must read within 10% at any time. Yes it is probably true that from new all cars over-read, but doubtfully not by as much as 10%. I find it unlikely that the starting point for any manufacturer would be at the extreme lower end of the limit otherwise any slight change in the variables of tyres would push it outside the legal limits. Such things as fluctuations in tyre temperature, vehicle weight, centrifugal forces and tread wear could all change the overall rolling diameter of the tyre, and therefore the reading on the speedo.
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as for the 1st bit thats exactly what i said there is a 10% cussion.
as for the 2nd bit what difference does it make if i type like that? u quite clearly could read it so...
i wouldnt try it, but a remapped mjet should do 145+
I was always lead to believe the speedo overreads by a certain amount as an 'error buffer'. So that if the speedo does become inaccurate/faulty etc chances are it will still display a speed greater then what you are actually doing.
All the cars i have driven (which is quite a few with work) and used sat nav/gps in have always overread the speed on the speedo.
All the cars i have driven (which is quite a few with work) and used sat nav/gps in have always overread the speed on the speedo.
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Because its ****ing annoying, you have a full keyboard so use it. You can understand what i say when written fully so type like that. Also there are a few members that dont use english as there first language so typing like that makes it practically impossible to understand.
It makes alot of difference.......if you (or anybody) can only be bothered to write 'text-talk' its simple ...I delete it.
Yeah thats basically it, new cars are built with a small buffer zone as it would be prohibitively expensive ensuring they are always 100% accurate.
Oh and to correct myself, Speedos are not tested in the MOT. However a working reference to the speed of the vehicle must be installed and be within the limits set by the The Road Vehicles (Construction and Use) Regulations otherwise it is not legal for driving on the public carriageway. Essentially it must not under-read, and it must not over-read by more than 10%. In my experience modern electronically controlled speedos tend to over-read by around 4% or so, giving a good margin either way on the legally defined limits.
So approximately, in a 50mph limit you could go around 59mph indicated speed and not be prosecuted based on the police guidelines. However this range varies from 57mph indicated for a fully accurate speedo to 63mph indicated if your speedo is at the opposite end of the legal limits.
angelegomezsd
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one time me and some friends managed to get some time in at an airstrip, and i managed to hit 130 mph on a 1.4 16v and still had quite a few revs to go, but i got scared cuz it felt like the car was going to desintegrate and didnt gas it anymore after 130. I probably wont ever go that high anymore.
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lol my standard Tjet only just managed to touch that on my private road so god knows how NA 1.4 got there.
Need to get it down the garage mate appears its obvious someones disconnected your turbo as you can only manage the same speed as the NA car
It must of took some doing getting back up such a steep hill as that "Airstrip" was built on
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With all this over reading stuff, I thought i'd highlight a key word that most people seem to be overlooking
Speedos generally[/]b over-read by about 10%
Some are more, some are less.
Judging solely by my sat nav...
An LDV Luton van I had was doing about 69 when the speedo read as 80
My Punto HGT over reads by 5-6mph at about 70.
My Lotus is pretty much spot on, 69 on the satnav is 70 on the speedo.
So the next time someone passes you in a Lotus and you think they are being an arse, consider this little fact
Chris
Speedos generally[/]b over-read by about 10%
Some are more, some are less.
Judging solely by my sat nav...
An LDV Luton van I had was doing about 69 when the speedo read as 80
My Punto HGT over reads by 5-6mph at about 70.
My Lotus is pretty much spot on, 69 on the satnav is 70 on the speedo.
So the next time someone passes you in a Lotus and you think they are being an arse, consider this little fact
Chris
OP
OP
It must of took some doing getting back up such a steep hill as that "Airstrip" was built on
Wasn't a jump jet airstrip with the big catapults was it?
P
i've heard that the remapped mjet's easily go off the clock with no trouble at all so i'd imagine easily 140 on the clock mate. I mean the tyres (if you've stuck with the manufacturer recommended one's) are rated to 150/155mph so there's no danger there and the 1.9 is a very strong engine so i can't imagine you causing any trouble...certainly not trying to test the top speed for a short period of time.
I've had my virtually standard starjet to 130 (all be it down hill and clock speed) and it was fine. Felt just as civilised as it does at 70/80 other than the fact that it was pretty high up the revs!!
I've had my virtually standard starjet to 130 (all be it down hill and clock speed) and it was fine. Felt just as civilised as it does at 70/80 other than the fact that it was pretty high up the revs!!
duncs04
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Just got a email from road angel this morning and it states the following:
Why is the speed reading on my Road Angel different to my vehicles speedometer?
When manufacturers calibrate the speedometer on your vehicle they have to take into consideration differing tyre pressures, sizes and tread. Every manufacturer has to ensure that at no point your vehicle is travelling faster than is indicated on the in-built speedometer, thus they calibrate it accordingly. It is also for this reason that your Road Angel is generally more accurate than your vehicles speedometer, however as it works on GPS signals, there is a one to two second time-lag for the display to update.
Tom
Why is the speed reading on my Road Angel different to my vehicles speedometer?
When manufacturers calibrate the speedometer on your vehicle they have to take into consideration differing tyre pressures, sizes and tread. Every manufacturer has to ensure that at no point your vehicle is travelling faster than is indicated on the in-built speedometer, thus they calibrate it accordingly. It is also for this reason that your Road Angel is generally more accurate than your vehicles speedometer, however as it works on GPS signals, there is a one to two second time-lag for the display to update.
Tom
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