Incorrect Speedo Speed. Need Advice On Calibration!

[advan]

Does anyone knows how to calibrate the speedo speed on R33? My speedo is 10km/h faster than the actual speed. Need help. Hope someone could give advice on calibating them. Cheers

[GTRsean]

Either change tyre diameter or take the speedo out and change the calibration resistor in the back of the speedo.

HPI magazine had an article on it a couple of issues ago on their R33 GTS 4 door with RB26DETT project.

[PranK]

Moving to General...

[dangerous_daveo]

If its in your favour leave it be. Saves getting speeding tickets

[izzy]

If its in your favour leave it be. Saves getting speeding tickets

not true having a uncalibrated spedo is a fine aswell!

dont kno if u loose demrit ppoints tho.. doubt it

[Birnie]

But there's no way they can check it

[hanyou]

haha umine is the same deal as you but everytime i hit boost the 'hundred thousand' number move... hahah so basically i go thru about 200,000kms a week

really do need to get that replaced lol..

its good in a way having it 10km/h up from wat it really is.. cause i find myself not speednig at all cause it already loooks like i am haha

[dangerous_daveo]

not true having a uncalibrated spedo is a fine aswell!

dont kno if u loose demrit ppoints tho.. doubt it

Yes but if you are 10kmh under the speedlimit. Good luck getting pulled over!

[Abo Bob]

haha umine is the same deal as you but everytime i hit boost the 'hundred thousand' number move... hahah so basically i go thru about 200,000kms a week

really do need to get that replaced lol..

its good in a way having it 10km/h up from wat it really is.. cause i find myself not speednig at all cause it already loooks like i am haha

hahaha

[sigsputnik]

i am pretty sure that jaycar makes an inline circuit kit to recalibrate your speedo. that's all the details i have though.

[baron25]

i am pretty sure that jaycar makes an inline circuit kit to recalibrate your speedo. that's all the details i have though.

Yeah, they do - catch is you've gotta be handy with a soldering iron, it's a DIY thing.

[Munkyb0y]

old thread, i know, but rather than risk a "use the search button" warning, i'll just add on here.

I had a GPS and a friend in my car (borrowed both, i have no friends).

He was watching the GPS screen for speed readout. Apparently, this unit updates 5 times per second, so i assume it's accurate.

At 60kph on speedo, the GPS stated 65kph.

At 110kph on speedo, the GPS stated 112kph.

This sounds backwards, does it not?

I have 18's on my car. And i assumed my speedo would be out a little.

But it looks to me as if the speedo/needle isnt really accurate, or the error/difference would have increased at higher speeds.

How have you guys found your R33 speedos to be?

[Konrad]

I have 3 spedos in my car - stock gtr cluster (in a s1 gts), blitz r-vit (consult connector style display unit) and gps. They all fluctuate... i assume the consult readout is the most accurate but the gps in particular can read anywhere from 90 - 110kph when the cluster reads 97 and the consult readout is 100kph..

[Munkyb0y]

hmmmm, so it may be the GPS that is out?

I thought those things were very accurate.

Edited September 20, 2006 by Munkyb0y

[Konrad]

i think it depends on how good the signal is at the time... if i'm crusing at a constant speed (well constant according to my other 2 spedos lol) it still fluctuates maybe 5kph?? I have a navman icn-320 if that helps (basic model one)

[mad082]

remember that some gps (depending on the type) aer only accurate to within 2m, so that can be enough to throw it out slightly, but not huge amounts.

[nsanity]

hmmmm, so it may be the GPS that is out?

I thought those things were very accurate.

the most accurate way to measure your speedo differential is to actually do the math.

RPM through gears into the diff with the Tyre/Wheel radius.

the ADR's allow for a 10% error in the Speedometer accuracy - ADR18

although the police do not seem to recognise this - specifically in victoria (3km/h over can and will get you a ticket..)

[Victory]

I have a "Road Angle" which is a form of GPS unit that stores the location of all fixed speed cameras, red light cameras etc etc and it also provides accurate speed readouts.

I would suggest that the accuracy of your speedo all comes down to your tyre size. I run a R33 GTR V-Spec and a R33 GTS-T Series II and the speedo readings are the same in each car for the same tyre size.

Exact Speedo reading = overall diameter of 651 mm

Typical Sizes :

275/30ZR19

275/35ZR18

245/40ZR18

245/45ZR17

5% over registration = speedo 105 and actual 100 = overall diameter 643

Typical Sizes :

265/30ZR19

265/35ZR18

235/40ZR18

235/45ZR17

11% over registration = speedo 111 and actual 100 = overall diameter 633

Typical Sizes :

225/50ZR16

[Munkyb0y]

well this is mine

5% over registration = speedo 105 and actual 100 = overall diameter 643

Typical Sizes :

265/30ZR19

265/35ZR18

235/40ZR18

235/45ZR17

but the gps was stating 112 at speedo-110, 65 at speedo-60.