| Author | Message | ||
     robert emmers (Rhemmers) New Member Username: Rhemmers Post Number: 10 Registered: 08-2003 |
I've done a mild OME lift on my '03 Disco and fitted 265-75-16s. Rides great, looks great, happy with it. I'm wondering about the speedo/odo. I checked the archives on this and found a variety of differing answers. Some indicated that the speedo was off to begin with and that the larger tires will actually make it more accurate. Others indicated I'd be off by varying percentages. Anybody have advice? Should I worry about getting the speedo recalibrated? Can it even be done relatively easyily? | ||
| quentin charles neil ross (Qcnr) New Member Username: Qcnr Post Number: 23 Registered: 10-2003 |
The easiest way to check is by using a GPS if you have that available. | ||
| Eugene (Eugene) Member Username: Eugene Post Number: 116 Registered: 02-2003 |
You have a couple of options to verify the speedometer's accuracy: 1) If a road you travel is marked off in mile intervals, you could use a stopwatch and time how long it takes to travel a mile. 2) Some towns have generator-powered devices that tell drivers how fast they are travelling. If you find one of those devices, see if the speedometer matches the reading on the device. 3) If you have access to a GPS, most will indicate your speed as well. I found that the speedometer on my '03 Disco is reading accurately with a tire size of 255/70/16. I'm not sure how easy it will be to get the speedo recalibrated. Perhaps someone else can chime in here... -Eugene | ||
| Lewis Jones (Cutter) Member Username: Cutter Post Number: 141 Registered: 10-2003 |
this should work... http://www.superlift.com/products/misc/truspeed.asp | ||
| ozwapet (Ozwapet) New Member Username: Ozwapet Post Number: 3 Registered: 07-2003 |
I found that with the stock 235/75 tyres the speedo read about 10% high for the actual speed but when I put on 245/75 tyres it was spot on ( as measured with a GPS ) I suspect with tyres your size it will read about 10% low. As has been said prviously, the best way to check is with GPS -can't get any more accurate than that. | ||
| Jamie (Rover_puppy) Senior Member Username: Rover_puppy Post Number: 420 Registered: 05-2003 |
I did the math when I changed tires and the numbers said that I was going to be going 17 mph faster than odometer indicated. I asked about having it recalibrated and was told at dealership that they did not do that. Funny thing though - when I tested speed with GPS my speed remained acturate on the odometer. | ||
| David Trammell (Discoconvert) New Member Username: Discoconvert Post Number: 13 Registered: 03-2003 |
I had the same results as Ozwapet. According to my GPS, with stock tires, my speedo said I was going faster than I really was. With 245/75's on now, the speedo and GPS match. Dave 99 D1 | ||
| David Seger (Croakus) Member Username: Croakus Post Number: 64 Registered: 06-2003 |
I've got a 2001 with lift and 265/75's. My GPS says 70 when the little arrow only says 65. Take that for what it's worth. | ||
| Robert Pate (Racerx) Member Username: Racerx Post Number: 59 Registered: 08-2003 |
Same findings 245/75/16's checked with GPS speedo dead on. | ||
| CALM (Gumarcel) Senior Member Username: Gumarcel Post Number: 1069 Registered: 11-2002 |
http://www.miata.net/garage/tirecalc.html | ||
| CALM (Gumarcel) Senior Member Username: Gumarcel Post Number: 1070 Registered: 11-2002 |
http://www.miata.net/garage/tirecalc.html | ||
| robert emmers (Rhemmers) New Member Username: Rhemmers Post Number: 11 Registered: 08-2003 |
Thanks for all the info. I don't have a GPS -- I guess they may be a good enough excuse to get one. I thought I'd check myself on the 210 toward Riverside yesterday but Southern California Freeways being as they are, I could distinguish the damn mile markers among all the rest of the stuff. Mostly it's the odometer I'm worried about -- hate to cheat myself out of part of my warranty. | ||
| Jeff Mclaird (Granitedisco) New Member Username: Granitedisco Post Number: 16 Registered: 08-2003 |
Best bet would be to see about getting the speedo recalibrated - there should be a number of shops out that side of the world that do it. | ||
| Peter Sharratt (Gummikuh) Senior Member Username: Gummikuh Post Number: 255 Registered: 02-2003 |
Hi Recalibration is easy,all you will need is the right colour speedo drive out of the side of the transfer box, this should be the same as a defender, which runs 235/85`s as standard and 265/75`s as an option. You will need to find the right number of teeth on the drive end. Probably easiest to just get a used defender transfer box from somewhere(UK) this will also give you better gearing for the bigger tyres in high range. Pete |
