SPEEDO ALMOST GOT ME 3 Points

[red_devil]

AAAAAAGGGHHHHH my speedo on my nova is fcukin way out.... i was doing 45 on my clock and the copper gatso'd me going 62.

I was lucky coz it was 1 in the mornin so he let me off but i really need to sort this before i lose my lisence..... HELP


car is on 16's and lowered 40mm if that helps

Cheers lads

[Alex]

is is a standard speedo?

[Ric 16v]

have u got a digi dash or standard clocks ???? if u have a digi dash the red switch on top of the dash could be in the wrong place making it not read right !!!!!

[red_devil]

its got 1 litre clocks but i've been told that i doesn't make a difference....

i want Digi Clocks but its a mk1 dash and its alot of effort to get them to fit

[Nova-Flair]

could be that your speedo cable is knacked?? have you ever had the needle off the speedo???

[Aragorn]

what are the specs on the tires ur running

plug em in below and that will tell u how far out that will be knocking your speedo

as an example:

using pi*d = circumference

where d = diameter of wheel in mm + twice the height of tire sidewall (ie the diameter of the entire wheel and tire

145/80R13 (standard 1litre steels) has a rolling circumference of:

( (13*25.4) + (145*0.8*2) ) * pi

= (330.2 + 232) * pi

= 1766.2mm (or 1.7m)

a 16" rim running a 195/45R16 tire is:

( (16*25.4) + (195*0.45*2) ) * pi

= (406.4 + 175.5) * pi

= 1828.1mm (1.8m)

If we devide the two:

we get 1.035 or 103.5%

this means the speedo is reading low by 3.5%

3.5% is obviously nothing

at 45mph indicated you'd infact be doing 46.7mph but if u check these figures against your tires and use your actual numbers u may find its a bit larger

the speedo can also be upto 10% out from the factory as this is the legal tolerance for the clocks

the only problem is they gatso'd you at 62 and thats like 50% faster

im not trying to be funny but throw all that theory outta the window and have a think

i know the difference between 40 and 60 mph and ive not even been driving for a year

the gearbox and engine most certainly know the difference, your not exactly tootling along at 1500rpm's at 60 mate

and the road noise is gonna be a damn sight more at 60 than 40

so i'd go get a new set of dials and pop them in - and if u cant tell the difference between 40 and 60 then i suggest u find out QUICKLY before u cause an accident or get yourself banned

[wisewood]

i suggest u find out QUICKLY before u cause an accident or get yourself banned

good point - wise words indeed.
worded a little harshly - but still a good point.

[Dicko]

cant be tyres unless hes running 22" rims :)

[ade]

have you fitted different dials? eg changed the backs for a set of lockwood white dials.

If so and you removed the needles its possible that they werent marked before taking off. This will throw out the calibration completely

Ade

[?Marty?]

Even if the speedo is out, you should still be able to tell the difference between 60ish and 45ish. Aspecially in a Nova of all cars. If you can't then maybe you shouldn't even be on the road.

[mowgli]

I suggest you get someone with a fairly new & not modified car to follow you on a decent straight piece of road at a constant speed and then compare notes.

The good gentlemen from Her Majesty's Constabulary have been known to take the wee wee over speeding before. The advise is to check & question everything they say whilst not actually admitting to anything. I used to work with a girl who got points cos the cops got her to admit what speed she was doing. They actually had no means on their car to check it properly.

P.S. Gatso's are those boxes on big sticks that are meant to be a visible deterent to dangerous driving, & not big money boxes....