[S13RR4]

So we all know that bigger tyres will put your speedo out.

But I was thinking today, since the tyres put your speedo out by a percentage (10% for me), could you not just replace the speedo backing scale thing with one 10% larger? (the scale not the size of the entire thing?)

Joe

[S13RR4]

So the new scale would have a spacing between 10 and 20 say, 10% further apart than the original?

[JrZook]

S13RR4 wrote:

So the new scale would have a spacing between 10 and 20 say, 10% further apart than the original?

Yes. Or you can play with the spring setup in the back of teh cluster to get it near spot on again

[Che]

I read a long time ago on some yank forum that the speedos are actually adjustable.

I reckon if you type in 'samurai speedo adjust' in google or something similar you'll find the answer

[S13RR4]

JrZook wrote:

S13RR4 wrote:

So the new scale would have a spacing between 10 and 20 say, 10% further apart than the original?

Yes. Or you can play with the spring setup in the back of teh cluster to get it near spot on again

this seems a little more fiddly, and possibly hit and miss

[S13RR4]

"Remove the frame (four bolts at corners), the glass (two screws between speedo and tach), the speedo needle (carefully pull it straight off), and the face of the speedo (two tiny screws on either side of needle post), and you'll see a lever to the left of the trip/odo meters. Move that lever UP to slow down the speedometer, and move it down to speed it up. Check it with just the face and needle in place (and if you have the top down put the glass on, too, so wind won't move your needle). As I said earlier, it took me three stops to zero it in."

[JrZook]

S13RR4 wrote:

this seems a little more fiddly, and possibly hit and miss

Hurmmm I actually have a CPU, and jig I setup to calibrate mine. Mite have to pull it out and get it operational again if ppl are interested....

[S13RR4]

..but there is one thing that everyone should know about this mod:

It only affects the way the speedometer operates to display your speed. It does nothing to adjust how your odometer calculates the miles that you have travelled! This is because the speedometer senses the rotation of the cable that drives the odometer through a spring-loaded mechanism. The adjustment described in the Zuwharrie post - and elsewhere- merely changes the loading on the sensing mechanism that drives the speedometer pointer to compensate for the change in roational speed caused by the change in gearing/tire size.

The only way to get your odometer calibrated for any change in gearing or tire size change is to install a compensating gearbox on the back of the speeedometer in line with the speedometer cable. A gearbox installation (speedometer shops do them) will also make your speedometer read correctly again.

I'm not putting this fix down - I'm only warning you not to expect magical results with your odometer and mileage improvements from it. This fix IS a good way to keep yourself from getting speeding tickets!

[JrZook]

S13RR4 wrote:

..but there is one thing that everyone should know about this mod:

It only affects the way the speedometer operates to display your speed. It does nothing to adjust how your odometer calculates the miles that you have travelled! This is because the speedometer senses the rotation of the cable that drives the odometer through a spring-loaded mechanism. The adjustment described in the Zuwharrie post - and elsewhere- merely changes the loading on the sensing mechanism that drives the speedometer pointer to compensate for the change in roational speed caused by the change in gearing/tire size.

The only way to get your odometer calibrated for any change in gearing or tire size change is to install a compensating gearbox on the back of the speeedometer in line with the speedometer cable. A gearbox installation (speedometer shops do them) will also make your speedometer read correctly again.

I'm not putting this fix down - I'm only warning you not to expect magical results with your odometer and mileage improvements from it. This fix IS a good way to keep yourself from getting speeding tickets!

Yes thats why I did mine. Not worried bout teh actual kms travelled. This is much more important

[S13RR4]

yeah my spread sheet that I put all my millage data into does that for me

[alien]

to get mine engineered i had to get the speedo calibrated (was done by adding more to the spring on the speedo) - there was no requirement for the odometer to read correctly (poorly worded law). either way my actual KM are 20% higher than my odometer... so when i get 250km to 30L according to the ODO its more like 300km.

Mines also a typical sierra which hasnt got a working fuel guage - so i refuel based on KM driven.

[SuziBlu]

GPS and a white marker.

[Che]

SuziBlu wrote:

GPS and a white marker.

Yep. I go off the GPS nowaday. There's a program for Tomtoms called Tripmaster... big arse numbers and your speed can be seen from 10 cars behind

[Rockhopper]

che_guitarra wrote:

SuziBlu wrote:

GPS and a white marker.

Yep. I go off the GPS nowaday. There's a program for Tomtoms called Tripmaster... big arse numbers and your speed can be seen from 10 cars behind

No good to you travelling through tunnels fitted with speed camera's, such as pretty much every tunnel in Sydney

[SuziBlu]

If you know by the GPS that at say 55k you are doing 60, the easy.

Do tis up to 110, or whatever your speed limit is, mark your speedo face with a texta if you cant remember.

At 100 my zook with 31s is doing 93, at 80 its doing 75 at 60 its doing about 57.

Its very easy and cheap, just uses brain power to remember.

[mondo]

i do the same as suziblu, just remember the percentage the speedo is out by. but this is still no speedo correction fix.
im not sure how this works on zooks, but i remember fooling around with diff gears on my old falcon, and i was able to buy different sized speedo drive gears, which compensated for the gear ratio, is this not a possibility for the zook?

[SierraDan]

I just remember the speeds too. Not hard you just get used to the habit.

Also I believe there are repeaters in the tunnels in Sydney.

[S13RR4]

Mines out by 10% so its a piece of cake to work out actual speed

Was just a point of discussion I thought might be good to put on here

[stockman]

Mine is a little more than 10% out

36 is 40
52 is 60
70 is 80

Thats going of the gps. I have made some stickes to stick on the cluster. Easy fix. Just got to stick them on.

[SierraDan]

31's are 12% out I believe.

[JrZook]

SierraDan wrote:

31's are 12% out I believe.

If in fact you are looking at a true measured 31" and your comparing it to a dead accurate speedo for 205/70r15 tires (stock 26.3") your looking at near 18% out

Aftermarket tire size comparison

215/75r15 = 5.2%
235/75R15 = 9.8%
30' = 14%
31' = 17.8%
33' = 25.5%

Dan

[crewsy]

SierraDan wrote:

I just remember the speeds too. Not hard you just get used to the habit.

x 2. You end up knowing how to be spot on after a while.

I also stick my iphone on my dash and use a speedometer application sometimes for long trips.

[taszook]

so can you get a replacement gear or something for the tcase? i would like it to be accurate for speed and distance. sure i can work out 10% easy enough but would be good if it was correct